Analytical Profiles of Drug Substances Volume 2
EDITORIAL BOARD
Norman W.Atwater Glenn A. Brewer, Jr. Lester Chafetz Edward M. Cohen Jack P. Comer Klaus Florey Salvatore A. Fusari
David E. Guttman Eric H.Jensen Arthur F.Xichaelis Stephen Id. Olin Gerald J. Papariello Bernard 2. Senkowski Frederick Tishler
ACADEMIC PRESS RAPID MANUSCRIPT REPRODUCTION
Analytical Profiles of Drug Substances Volume 2 Edited by
Klaus Florey The Squibb Institute for Medical Research New Brunswick, New Jersey
Contributing Editors,
Glenn A. Brewer, Jr. Lester Chafetz Edward M.Cohen David E. Guttman
Stephen M. Olin Gerald J. Papariello Bernard Z. Senkowski Frederick Tishler
Compiled urider [he auspices of [he Phartnnceutical Analysis ant1 Control Section Academy of Phnrniac.eiitica1 Sciences
Academic Press NewYork and London 1973
1973, BY THEAMERICAN PHARMACEUTICAL ASSOCIATION COPYRIGHT ALL RIGHTS RESERVED NO PART O F THIS BOOK MAY BE REPRODUCED IN ANY FORM, BY PHOTOSTAT, MICROFILM, RETRIEVAL SYSTEM, OR ANY OTHER MEANS, WITHOUT WRITTEN PERMISSION FROM THE PUBLISHERS.
ACADEMIC PRESS, INC.
111 Fifth Avenue, New York, New York 1wO3
United Kingdom Edition published by ACADEMIC PRESS, INC. (LONDON) LTD.
24/28 Oval Road, London NW1 IDD
LIBRARY OF
CONGRESS CATALOO CARD
NUMBER:70-187259
PRINTED IN THE UNITED STATES OF AMERICA
CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .
AFFILIATIONS OF EDITORS, CONTRIBUTORS, A N D REVIEWERS FORICWORD PREFACE .
. . . . . . . . . . . . . . . . . . . . . .
vii ix xi
Ampicillin . . . . . . . . . . . . . . . . . . . . . . Eirgene I i m l i liiv
1
Chlorprot hixene . . . . . . . . . . . . . . . . . . . . Bruce C Rir& and Berriard 2.S e i i h o ~ ~ s h - i
63
Chloral Hydrate . . . . . . . . . . . . . . Johti E. Fuirbrotlier
85
Clidinium Bromide . . . . . . . . . . . . . Bruce C. Rutlj. arid Berriard Z. Senkowski
145
Dexarnethasone . . . . . . . . . . . . . Edward M. Coheri
163
Dioctyl Sodium Sulfosuccinate . . . . . . . . . . . . . . S l i t Airiija and Jerold Coireri
199
Fluorouracil . . . . . . . . . . . . . . . Bruce C. R i d y arid Berriurd Z. Serikowski
22 1
Fluphenazine Enanthate . . . . . . . . . . . . . . . . . Kbirs Florev
245
Fliiphenazine Hydrochloride . . . . . . . . . . . . . . . Klairs Florey
263
Isocarboxazid. . . . . . . . . . . . . . . . . . . . . Bruce C. Riillj, atzd Bernard Z Serikowski
295
Isopropaniide . . . . . . . . . . . . . . . . . . . . . Ralph S. Satitoro, Richurd J. Warrcn, Geriild D. Roberts, Ecl\z.urtl White, V. arid Peter P Begosli
3 I5
CONTENTS
Levallorphan Tartrate . . . . . . , . . . Bruce C. Rudy and Bernard Z. Senkowski
. . . . . . . .
339
Methyprylon . . . . . . . . . , . . . Bruce C. Rudy and Bernard Z. Senkowski
.
Phenelzine Sulfate . Robert E. Duly
. . . .
Primidone . . . . . Raymond D. Daley
.
.
.
. .
. . .
.
.
363
. . . . . . . .
.
. .
. .
3 83
. . . . . . . .
.
. . . . .
409
.
. .
. .
439
. . . .
.
467
Propiomazine Hydrochloride . . . . . . Kathleen B. Crombic and Leo F. Cullen
. .
.
.
.
Sulfamethoxazole . . . . . . . , . . . Bruce C. Rudy and Bernard Z. Senkowski
.
Sulfisoxazole . . . . . . . . . , . . . Bruce C. Rudy and Bernard Z. Senkowski
. .
.
. . . .
.
487
Triclobisonium Chloride . . . . . . . . . . . Bruce C. R u d y and Bernard Z. Senkowski
.
.
. .
.
507
. . . .
. . .
.
.
,
. . .
523
Trimethobenzamide Hydrochloride . . . . Kenneth W. Blessel, Bruce C. Rudy, and Bernard Z. Senkowski
. . .
.
. . . . .
55 1
Triflupromazine Hydrochloride Klaus Florey
ADDENDA. . . . ERRATA.. . . . CUMULATIVE INDEX
.
. . . . . . . . . . . . . . . . . . . . . . . . . . .
vi
. . . . . . . . .
. .
. . . . . .
.
. . . . . . 571 . . . . . 573 . . . . . 5 75
AFFILIATIONS OF EDITORS, CONTRIBUTORS, AND REVIEWERS
S. Ahuju, Ciba-Geigy Inc., Ardsley, New York N . W. A trvater, Searle and Co., Chicago. Illinois
P. P. Begosh, Smith, Kline and French Laboratories, Philadelphia, Pennsylvania
K. W. Blessel, Hoffmann-La Roche Inc., Nutley, New Jersey G. A . Brewer, Jr., T h e Squibb Institute for Medical Research, New Brunswick, Now Jersey
L. Clzufbtz, Warner-Lanibert Research Institute, Morris Plains, New Jersey
E: M. C'olzeti, Merck, Sharp and Dohme. Westpoint, Pennsylvania J. Colirw, Ciba-Geigy lnc., Ardsley, New York
J. P. C o / ~ c rEli , Lilly and Company, Indianapolis, Indiana
K. 5.Crornhie, Wyeth Laboratories, Philadelphia, Pennsylvania L. F. Cirlletz, Wyeth Laboratories, Philadelphia, Pennsylvania R. D. Dalc,y, Ayerst Lahoratories, Rousses Point, New York R. L'. D U / I ~Warner-Lambert . Research Institute, Morris Plains, New Jersey J. ELFuirhrotlicr, The Squibb Institute for Medical Research, Moreton, Wirral, England
K. Florcy, The Squibb Institute for Medical Research, New Brunswick, New Jersey S. A . Ft.r.suri. Parke, Davis and Company, Detroit, Michigan
D. E. Girttnian, School of Pharmacy, University of Kcntucky. Lexington, Ke ti t uc k y
vii
AFFILIATIONS OF EDITORS, CONTRIBUTORS, AND REVIEWERS
E. ivashkiv, The Squibb Institute for Medical Research, New Brunswick, New Jersey
E. H . Jensen, The Upjohn Company, Kalamazoo, Michigan
J. Kuzan, American Cyanamid, Bound Brook, New Jersey A . F. Michaelis, Sandoz Pharmaceuticals, East Hanover, New Jersey S. M . O h ,Ayerst Laboratories, New York, New York
G. J. Papariello, Wyeth Laboratories, Philadelphia, Pennsylvania
T. E. Ricketts, American Cyanamid, Bound Brook, New Jersey G. D.Roberts, Smith, Kline and French Laboratories, Philadelphia, Pennsylvania
B. C. Rudy, Hoffmann-La Roche Inc., Nutley, New Jersey R . S. Suritoro, Smith, Kline and French Laboratories, Philadelphia, Pennsylvania
B. Z. Senkowski, Hoffmann-La Roche Inc., Nutley, New Jersey F. Tishler, Ciba-Geigy Inc., Ardsley, New York R. J. Warrer?, Smith, Kline and French Laboratories, Philadelphia, Pennsylvania
E. White, V , Smith, Kline and French Laboratories, Philadelphia, Pennsylvania
viii
FOREWORD The concept for gathering together and publishing pertinent information on the physical and chemical properties of various official and new drug substances had its origin with the members of the Section on Pharmaceutical Analysis and Quality Control of the Academy of Pharmaceutical Sciences. More than two years of consideration preceded the authorization of this ambitious project by the Executive Committee of the Academy in the Spring of 1970. The immediate and virtually spontaneous enlistment of the first group of contributors t o this work attested t o its importance and the wisdom of pursuing its publication. By coincidence, the delegates t o the sesquicentennial anniversary meeting of the United States Pharmacopeial Convention, Inc., in Washington, D.C. on April 8-1 0, 1970, adopted the following resolution: Whereas widespread interest has been expressed in the inclusion of additional information about physical and chemical properties of drugs recognized in the United States Pharmacopeia Be It Resolved that the Board of Trustees consider publishing in the Pharmacopeia, or in a companion publication, information on such attributes as solubilities, pH and pK values, spectra and spectrophotometric constants, and stability data, pertaining to pharmacopeial drugs.
The U.S.P.C. Board of Trustees unanimously approved the resolution in principle on June 4, 1970 and authorized the Director of Revision t o include in the U.S.P. monographs such physical-chemical information as he deemed proper and also to cooperate with the Academy of Pharmaceutical Sciences to secure the publication of other physical-chemical data. It was my privilege to be the President of the Academy during the period when Arialyticai Profiles was under consideration. I t is my unusual and unique honor as President of the Academy and Director of U.S.P. Revision to assist in the institution and dedication of this first volume. I trust that it will serve immeasurably in providing the scientific community with an authoritative source of information on the properties of many of our important drug compounds.
Jar1irar.v 19 71
Thomas J. Macek
This Page Intentionally Left Blank
PREFACE Although the official compendia define a drug substance as to identity, purity, strength, and quality, they normally d o not provide other physical or chemical data, nor d o they list methods of synthesis or pathways o f physical or biological degradation and metabolism. At present such information is scattered through the scientific literature and the files of pharmaceutical laboratories. For drug substances important enough to be accorded monographs in the official compendia such supplemental information should also be made readily available. To this end the Pharmaceutical Analysis Section, Academy of Pharmaceutical Sciences, has started a cooperative venture to compile and publish Anulyricul Profiles of Drug Substunces in a series of volumes of which this is the second. It is also planned to revise and update these profiles at suitable intervals. Our endeavor has been made possible through the encouragement we have received from many sources and through the enthusiasm and cooperative spirit of our contributors. For coining the term Analytical Profile we are indebted to Dr. James L. Johnson of the Upjohn Company. We hope that this, our contribution to the better understanding of drug characteristics, will prove to be useful. We welcome new collaborators, and we invite comment and counsel to guide the infant to maturity. Klaus Florey
xi
This Page Intentionally Left Blank
T
Eiigerie Ivushkiv
1
EUGENE IVASHKIV
Table of Contents Page Description 1.1 Name:Ampicillin 1.2 Formula and Molecular Weight 1.3 Isomers 1.4 Hydrates 1.5 Salts 1.6 Appearance, Color and Odor 2. Physical Properties 2.1 Spectra 2.11 Infrared Spectra 2.12 Nuclear Magnetic Resonance Spectra 2.13 Mass Spectroscopy 2.14 Ultraviolet Absorption 2.2 Crystal Properties 2.21 Crystalline Modification of Ampicillin 2.22 X-ray Diffraction 2.23 Melting Range 2.24 Differential Thermal Analysis 2.25 Thermal Gravimetric Analysis 2.3 Solubility 2.4 Ionization Constant, pK 2.5 Optical Rotation 3. Ampicillin Stability 3.1 Modes of Penicillin Degradation 3.2 Stability of Ampicillin in Solution 3.3 Stability of Ampicillin Powders 3.4 Cupric Ion-Catalyzed Hydrolysis 4. Methods of Manufacture 4.1 Microbiological 4.2 Chemical 5. Isolation and Purification 6. Methods of Analysis 6.1 Identification Tests
1.
2
4 4 4 4 4
5 5 5
5 5 8
12 16
17 17 18 18
18 20 20 20 20 23 23 25 32 32 32 32
33 37 37 37
AMPICILLIN
Page 6.2 6.21
7. 8. 9.
O u a n t i t a t i v e Methods U l t r a v i o l e t Spectrophotom e t r i c Methods 6.22 Fluorometric Determination 6.23 Polarographic Determination 6 . 2 4 T h i n Layer Chromatography 6.25 P a p e r Chromatography 6.26 Iodometric T i t r a t i o n 6 . 2 7 Hydroxamic Acid 6 . 2 8 Amperometric T i t r a t i o n 6 . 2 9 M i c r o b i o l o g i c a l Methods P r o t e i n Binding Pharmacok i n e t i c s References
3
38 38 39 39 39 40 41 41 42 42 43 45 47
EUGENE I V A S H K I V
1.
Description
Name: Ampicillin AmpicillinL,L,jis designated by Chemical Abstracts as Q- (2-amino-2-phenylacetamido)-3,3-dimethyl-oxo-4-thia-l-azabicyclo 17.2.0-7 heptane-2-carboxylic acid. Ampicillin is also known as bb(-)-a-aminophenylacetamidd penicillanic acid, Q ( - ) -a-aminobenzylpenici llin4 and a-aminobenzylpenicillin5. 1.1
1.2
Formula and Molecular Weight
0
C)H l€12- C-N II I
I
C16H1 9N304S
349.41
Isomers The presence of a symmetric C atom in the side chain provides optical isomer6. The D-isomer, I)(-)-a-aminobenzylpenicillin, is more active than the &-isomer, L(-)-a-aminobenzylpenicillin7. The s nthesis of ampicillin epimer has been reported8 1.3
3
8,
1.4
Hydrates It has been re orted that ampicillin can exist in anhydrous sesquihydrate16 and trihydrate Austin, et al. postulate that ampicillin exists in anhydrous or trihydrate forms only. Refer to section 2.21.
4
AMPICILLIN
1.5
Salts P o t a s s i u m a n d sodium s a l t s o f a m p i c i l l i n 2 0 - 2 9 , human l y s o z me a m p i c i l l i n s a l t 3 ! 2-nitro-l,3-indandione salt3', and t h e a m p i c i l l i n s a l t of k a n a m y c 1 r - 1h ~ a~v e b e e n p r e p a r e d . 1.6
A p p e a r a n c e , C o l o r a n d Odor Ampicillin i s a free-flowing, white I t h a s an o d o r c h a r a c t e r i s t i c c r y s t a l l i n e powder. of p e n i c i l l i n s .
2.
Physical Properties
2.1
Spectra
2.11
Infrared Spectra S u b s t i t u t e d monocyclic O-lactams i n s o l u t i o n show c a r b o n y l a b s o r p t i o n w i t h i n t h e t h e B-lactam r i n g i s r a n g e 5 . 6 8 - 5 . 7 8 ~ ~ ~ When . fused t o a t h i a z o l i d i n e r i n g , the carbonyl a b s o r p t i o n occurs i n t h e range 5.62-5.651. Morin a n d c o - ~ o r k e r sh~a v~e n o t e d r o u g h c o r r e s p o n d e n c e b e t w e e n t h e f r e q u e n c i e s o f t h e f3-lactam c a r b o n y l a b s o r p t i o n and t h e b i o l o g i c a l a c t i v i t i e s of a s e r i e s of p e n i c i l l i n d e r i v a t i v e s . The i n f r a r e d s p e c t r a o f p e n i c i l l i n analogues have been discussed35. The i n f r a r e d s p e c t r u m o f a m p i c i l l i n t r i h y d r a t e was m e a s u r e d on a P e r k i n - E l m e r Model 2 1 double-beam s p e c t r o p h 0 t o m e t e r 3 ~ . The i n f r a r e d a b s o r p t i o n o f p e n i c i l l i n d e r i v a t i v e s h a s b e e n r e c o r d e d and Figure 1 and Figure 2 a r e t h e discussed37. s p e c t r a of t h e Squibb Primary Reference S u b s t a n c e s o f a m p i c i l l i n t r i h y d r a t e and anhydrous a m p i c i l l i n r e c o r d e d a s m i n e r a l o i l m u l l and p o t a s s i u m b r o m i d e p e l l e t s w i t h a P e r k i n - E l m e r Model 2 1 spectrophotometer. I n t e r p r e t a t i o n of t h e spectrum of a m p i c i l l i n t r i h y d r a t e h a s been rep ~ r t e d ~ ~ ai sn dg i v e n i n T a b l e 1. 5
F i g u r e 1.
I n f r a r e d Spectrum of Ampicillin T r i h y d r a t e Squibb Reference Standard.
FREQUENCY ( c M - ~ )
WAVELENGTH IMICRONSJ
F i g u r e 2.
I n f r a r e d S p e c t r u m o f Anhydrous A m p i c i l l i n S q u i b b Reference Standard.
EUGENE I V A S H K I V
Table I I n f r a r e d Spectrum of A m p i c i l l i n T r i h y d r a t e I R A b s o r p t i o n Band,
Interpretation
2.9 3.1 weak b a n d s 3 . 5 - 4 . 8 5.65 5.90 6 . 2 and 6 . 3 5 6.7
H20 N' H NH3+ @-lactam C = 0 Amide C = 0 + COO-, NH3 Aromatic r i n g , Amide 11, NH3+ 14.4 Monosubs t i t u t e d aromatic r i n g . I n t h e s o l i d form, a m p i c i l l i n t r i h y d r a t e e x i s t s a s t h e z w i t t e r i o n a n d t h e i n f r a r e d s p e c t r u m shows a b s o r p t i o n s t y p i c a l o f t h i s t y p e o f compound38. 2.12
N u c l e a r Magnetic Resonance S p e c t r a NMR s p e c t r a o f p e n i c i l l i n d e r i v a t i v e s i n d i f f e r e n t s o l v e n t s w e r e r e c o r d e d on a 1 0 0 MHz spectro~neter~R ~ e. c e n t l y , s t r u c t u r a l s t u d i e s w i t h l3c n u c l e a r m a g n e t i c r e s o n a n c e w e r e r e p o r t e d 4 0 €or p e n i c i l l i n s . I 3 c Chemical s h i f t a s s i g n m e n t s were made f o r t h e d i f f e r e n t c a r b o n NMR s p e c t r a i n D 2 0 s o l u t i o n s o f t h i r t e e n atoms. p e n i c i l l i n d e r i v a t i v e s h a v e b e e n r e c o r d e d and a n d Puar'' s t u d i e d NMR i n t e r ~ r e t e d ~ Cohen ~ . s p e c t r a of a m p i c i l l i n t r i h y d r a t e i n d e u t e r o d i m e t h y l s u l f o x i d e (DMSO-d6) a n d D 2 0 - D C 1 . Tetram e t h y l s i l a n e was u s e d a s a n i n t e r n a l s t a n d a r d . The V a r i a n XL-100-15 NMR s p e c t r o p h o t o m e t e r was used. I n t h e c a s e of D M S O - ~ ~B,- l a c t a m p r o t o n s c o u l d be e a s i l y d i s t i n g u i s h e d b y t h e i r c o u p l i n g pattern. The NMR s p e c t r a of t h e S g u i b b P r i mary R e f e r e n c e S u b s t a n c e a r e g i v e n i n F i g . 3 a n d F i g . 4 . The a s s i g n m e n t s a r e r e p o r t e d i n T a b l e 11. 8
9
u)
I
a
fn C .d
a, m
k
4J
$1
a
c
4
C
k E
u
.d rl rl -d -d
$ 0
rCI
5 k
a,
u
4J
a w
x m a, k
7
0-l
Irr
.rl
c
0
" e ? , , , , . , , ,
/ , , ,
Figure 4 .
, , , ,
, . , ,
,
,
/
,
, , , , , , . ,
1
, , , , I , , , ,
m
/ , , , , , , , ,
,
,
,
,
1
,
1
"
"
'
,
"
"
,
,
1
,
NMR Spectrum of Ampicillin T r i h y d r a t e in D20-DC1.
,
,
'
,
'
,
,
'
~
,
'
,
'
,
'
'
'
,
~
~
'
'
T a b l e I1 Proton-resonance
DMSO-d6
2H
3H
5H ,
1.39
1.39
5.39q
(9.0, 4.0)
5.39d
(4.0)
1.49 D20-DC1 e
1.41
4.47
6H
5.54
Lines
7H
8H
9
10
5.95b
4.84
7.36m
4.6433
5.26
7.53
>
5
1.44
6
5
c
EUGENE I V A S H K I V
2.13
Mass Spectroscopy The behavior of the penicillins in the mass spectrometer has been studied by several investigators. The fragmentation of penicillin V has been discussed by Kukolja, et a1 42. Richter and Biemann43examined penicillins G and V methyl esters and made numerous accurate mass measurements at high resolution. The nucleus fragmentation by four different routes is shown in Fig.5. Bochkarev, et al. 42 studied various penicillin derivatives substituted at the carbonyl group and showed that it was possible to deduce the nature of this substituent from the mass spectrum. The mass spectrum of ampicillin trihydrate was determined by Funke and C ~ h e n ~ ~ and is shown in Figure 6. They prepared a disilyl derivative using N,O-bis (trimethylsilyl)acid amide dissolved in pyridine. The mass spectrum exhibits the molecular ion, M+, of m/e 493 €or the disilyl derivative. The more intense M+ -15 ion at m/e 478 is due to loss of methyl radical. The m/e 421 ion corresponds to the loss of Si(CH3)2CH2 from the molecule or the mono-silyl derivative while the ion 15 amu lower at m/e 406 has lost a methyl group in addition to the silyl function. The diagnostic fragment ion at m/e 178 €or silyl derivatives of penicillins demonstrates the presence of 6-aminopenicillanic acid ( 6 - A P A ) function. In addition, the ion at m/e 106 also is diagnostic for the non-silanized phenylqlycyl derivative. The intense ion at m/e 232 is diagnostic €or all penicillin derivatives. The mass spectral assignments are summarized in Figure 7.
AMPICILLIN
F i g u r e 5.
__+
b
__+
c - - c
P e n i c i l l i n Fragmentation
RCHzCONHCH=C=O
lt.
Me2C==CHCO,Mclt' RCH2CONH
RCH~CO~HCH
H?
Me
1 N-'
/
R e p r o d u c e d w i t h p e r m i s s i o n from A d v a n c e s i n Druq R e s e a r c h , Vol. 6 , p. 2 0 0 , A c a d e m i c P r e s s , New York, 1971.
13
i EUGENE IVASHKIV RELATIVE
~
~
~
r
INTENSITY
n
-
O
c
)
-
m
-
m
l
PERCENT TOTAL IONIZATION 39
Figure 6 .
Low R e s o l u t i o n Mass Spectrum of A m p i c i l l i n Trihydrate Squibb House Standard. 14
r
n
AMPICILLIN
178
231
I
I
+
H
1
m/e
178
+
t
m/e
Fig. 7.
106
Fragmentation of Ampicillin Derivative.
IS
EUGENE IVASHKIV
2.14
U l t r a v i o l e t Absorption U l t r a v i o l e t spectra of ampicillin t r i h y d r a t e , Squibb Primary Reference Substance were r e c o r d e d on a C a r y Model 1 5 s p e c t r o p h o t o meter46 a n d E l % values calculated. The r e s u l t s a r e g i v e n i n 4aF€'e 111.
T a b l e I11 U l t r a v i o l e t Absorption of A m p i c i l l i n T r i h y d r a t e W a v e l e n g t h , nm Phosphate b u f f e r pH 5 . 3 E 1%
2 57
262
268
8.69
7.81
5.61
257
262
268
7.94
6.69
4.55
2 58
2 68
-
7.28
5.03
1 cm P h o s p h a t e b u f f e r pH 7 . 0
1% 1 cm Phosphate b u f f e r 9.5 E 1% 1 cm
With t h e i n c r e a s e o f pH o f b u f f e r s o l u t i o n El% decreases. N o p e a k a t 268 nm i n cm p H 9 . 5 b u f g e r was o b t a i n e d . Saturated methanolic ampicillin t r i h y d r a t e s o l u t i o n s p r o d u c e d maximum a b s o r p t i o n a t 2 5 8 , 262 a n d 268 nm46.
16
AMPICILLIN
2.2
Crys ta 1 Properties
Crystalline Modification of Ampicillin Ampicillin crystallizes into two forms depending on the temperature of the aqueous solution 19. Anhydrous ampicillin is obtained from aqueous solutions at temperatures above 6OoC; the trihydrate is obtained from aqueous solutions at temperatures below 5OoC. The existence of anhydrous, monohydrate, sesquihydrate and trihydrate fo-ms of ampicillin was It has been shown by x-ray dif fr a ~ t i o nthat ~ ~ ampicillin monohydra te existed. Austin et.al.19 - concluded from a study of the infrared spectra of various forms of crystalline ampicillin that only the anhydrate and trihydrate exist. They believed the other hydrates were either amorphous or partially dehydrated t r i h ~ d r a t e Crystals ~~. of anhydrous and trihydrate ampicillin were prepared. James and Hall reported crystallographic data for ampicillin trihydrate. They showed that ampicillin exists as a zwitterion with three water molecules extensively involved with ~ ~ hydrogen bonding. Grant and A l b ~ r nhave distinguished between a crystalline anhydrous form and a monohydrate, which differ in solidstate infrared spectra, density, solubility and th erma 1 stab i1ity Anhydrous amp ic i 11in wa s prepared from any form of ampicillin but reasonably rapid conversion of trihydrate required a temperature 80°-1000C19. Hydrated ampicillin was also converted into an anhydrate by heating a suspension in nitromethane or other nitrohydrocarbons. 2.21
.
17
EUGENE IVASHKIV
2.22
X-ray D i f f r a c t i o n S i n g l e - c r y s t a l x-ray d i f f r a c t i o n w a s u s e d t o d e d u c e t h e s t r u c t u r e of b e n z y l p e n i illi in^^. S e v e r a l s a l t s o f b e n z y l p e n i c i l l i n was a n a l y z e d a n d b o n d l e n g t h s determined5'. X-ray d i f f r a c t i o n a n a l y s i s o f an h y d ro u s a m p i c i l l i n a n d a m p i c i l l i n m o n o h y d r a t e were p e r f o r m e d by T.Doyne a n d r e p o r t e d 4 7 . F i g . 8 shows t h e x - r a y d i f f r a c t i o n o f a m p i c i l l i n and g i v e s t h e d v a l u e s c h a r a c t e r i s t i c o f t h i s c r y s t a l form o f a m p i c i l l i n t r i h y d r ate51. M e l t i n q Ranqe A m p i c i l l i n monohydrate melts w i t h decom o s i t i o n a t 202OC a n d s o d i u m a m p i c i l l i n a t 205°Cf4, s e s q u i h y d r a t e a n d a n h y d r o u s a m p i c i l l i n decompose a t 199-202°C16. The m e l t i n g r a n g e f o r a m p i c i l l i n t r i h y d r a t e with decomposition a t 214.5O - 215.5OC was r e p o r t e d 5 2 a n d m e l t i n g w i t h d e c o m p o s i t i o n h a s b e e n r e p o r t e d a t 202O- 204OC by another i n v e s tiga tor5?
2.23
2.24
D i f f e r e n t i a l Thermal A n a l y s i s Jacobson54 r e c o r d e d d i f f e r e n t i a l therma 1 a n a l y s i s c u r v e s o f a m p i c i l l i n tr i h y d r a te, S q u i b b P r i m a r y R e f e r e n c e S u b s t a n c e , o n a DuPont D i f f e r e n t i a l Thermal Analyzer w i t h a t e m p e r a t u r e r i s e o f 15O p e r m i n u t e . E n d o t h e r m i c steps a t 88O,92O, a n d a l a r g e e n d o t h e r m a t 100°C were observed. Some s a m p l e s of a m p i c i l l i n t r i h y d r a t e h a d a s i n g l e l a r g e e n d o t h e r m a t 125OC w h i l e Y i h e r s h a d t h e l a r g e e n d o t h e r m a t a b o u t 105O- llO°C D i f f e r e n t i a l thermal a n a l y s i s f o r t h e c o n t r o l o f It phase t r a n s f o r m a t i o n of a m p i c i l l i n i s used55. h a s b e e n f o u n d t h a t t h e r m o g r a m s were r e p r o d u c i b l e f o r a g i v e n l o t of a m p i c i l l i n t r i h y d r a t e b u t v a r i e d from lot t o l o t . The p h a s e t r a n s f o r m a t i o n of a m p i c i l l i n t r i h y d r a t e b y t h e d i f f e r e n t i a l t h e r m a l a n a l y s i s u n d e r p r e s s u r e was s t u d i e d 5 6 .
.
18
AMPICILLIN
19 0
w
c
!4
Figure 8. X-Ray Diffraction Pattern of Ampicillin Trihydrate
EUGENE I V A S H K I V
2.25
Thermal Gravimetric Analysis A DuPont Thermogravimetric Analyzer, Model 950, indicated total volatile material to be 13.8% in ampicillin trihydrate Squibb Primary Reference Substance54. The theory is 13.39%. 2.3
Solubility The solubilities of anhydrous ampicillin, ampicillin trihydrate and sodium ampicillin from two manufacturers in various solvents were determined by Marsh and we is^^^. They found a variation in the solubility of sodium ampicillin from two different manufacturers and indicated this could be due to crystalline structure. The results are reported in Table IV. Anhydrous ampicillin and ampicillin trihydrate were compared for solubility in distill d water at temperatures ranging from 7.50 to 5OoC 58, 2.4
Ionization Constant, pK
Rapson constants for 0.004 and pK Russo-Alesi66 hydrate to be = 2.66 f 0.03 2.5
and Bird5' reported ionization ampicillin to be: pK1 = 2.53 f - 7.24 f 0.02. Jacobson and calculated pK2 for ampicillin tri7.24. Hou and PooleG1 reported pK1 0.03. and pK2 = 7.24
Optical Rotation Reference
+
Ampicillin monohydrateL-d21 D (C = 1 in H20)
- - 20
Ampicillin sesquihydrateL a 4 (C = 1 in H20)
281° 14
+ 283.1° 16
-+ 209' Sodium Ampicillin/-az20 ( C = 0.2 in H20) 2o
-_
Anhydrous AmpicillinL ( C = 1 in H20)
%
+
14
287. go 16
20
Table I V S o l u b i l i t y of Amp icillin
(mg/ml)
Ampicillin Solvent
h) i
Anhydrous
Water Me t h a n o 1 Ethanol Isopropanol Isoamyl a l c o h o l Cyclohexane Benzene Petroleum E th er Isooctane Carbon T e t r a c h l o r i d e Ethyl Acetate Isoamyl A c e t a t e Acetone Methyl E t h y l Ketone Diethyl Ether Ethylene Chloride 1,4-Dioxane Chloroform
10.098 2.968 0.390 0.055 0.125 0.048 0.002 0.010 0.0 0.008 0.025 0.030 0.125 0.052 0.022 0.032 0.595 0.095
Na S a l t I*
> 20 P20 v 20 1. 13 1.902 0.075 0.022 0.025 0.022 0.032 0.035 0.105 0.518 0.178 0.022 0.060 1.375 0.118
Na S a l t 11*
T r ihydrat e
> 20 > 20
7.558 6.649 2.538
19.780 6.405
19. 300 0.0 0.0 0.0 0.0 0.0
0.058 0.048
7 20 720 0.0 0.032 1.845 0.155
0.068 0.032 0.038 0.022 0.025 0.225 0.078 8.952 2.790 0.03 0.068 2.772 0.075 continued..
.
Table IV.
Solubility of Ampicillin (mg/ml), continued Ampicillin
Solvent
13
h)
Carbon Disulfide Pyr i dine Formamide Ethylene Glycol Propylene Glycol Dime thylsul fox ide 0.1N NaOH
0.1N H C 1
Anhydrous
0.015 2.100 20 18.415
2.230 20 20 20
Na Salt I*
0.010 3.256 20 20 20 20 20 20
Na Salt I1
0.0 20 20 20 20 20 20 20
*
Trihydrate
0.022 12.131 20 19.128 4.138 20 20 20
rn C
GI
rn
z rn -
27 687 ( 1 9 7 1 ) ; C . A . 7 6 , 498694. ( 1 9 7 2 ) . Hou, J. a n d P o o l e , J.W., J . P h a r m . S c i . 58, 447 ( 1 9 6 9 ) . a n d Sommers, B . E . , Bull. Allen, L . V . , Jr. Parenter. 210 ( 1 9 7 1 ) . Drug A s s o c . S c i . , 60, 1273 H., Bundgaard, (1971). J a c o b s o n , H. a n d R u s s o - A l e s i , F . , The S q u i b b I n s t i t u t e f o r Medical Research, P r i v a t e C o m m u n i c a t i o n , 1 9 6 9. J a c o b s o n , H. and R u s s o - A l e s i , F . , The S q u i b b I n s t i t u t e f o r Medical Research, P r i v a t e Communication, 1969, G e o r g e , M. J . , T h e S q u i b b I n s t i t u t e for Medic a l R e s e a r c h , P r i v a t e Communication, 1964. Sherman, C . and R u s s o - A l e s i , F . , The S q u i b b I n s t i t u t e f o r Medical Research, P r i v a t e
-
69.
70. 71. 72. 73. 74.
75.
-
-
2,
76. 77.
78.
79. 80.
.
51
EUGENE IVASHKIV
81.
82.
83. 84. 85.
86. 87. 88.
89. 90.
Commun i c a t i o n , 1 9 6 4 . S h e r m a n , C . , a n d R u s s o - A l e s i , F . , The S q u i b b I n s t i t u t e €or Medical Research, P r i v a t e Commun i c a t i o n , 1 9 6 9 . M a s s e y , M . A . , T h e S q u i b b I n s t i t u t e f o r Medic a l R e s e a r c h , P r i v a t e Communication, J a n u a r y 4 , 1964. F e r r e r o , E . , I n t . Congr. Chemother. P r o c . , 5 t h , 1 9 6 7 , (l), 201-5 ( F r , ) . Gradnik, B . , B o l l . SOC. I t a l . B i o l . Sper. 4 4 , 1 5 6 8 ( 1 9 6 8 ) : C . A . -, 70 95377k ( 1 9 6 9 ) . Mine Y a s u r i k o , N i s h i d a M i n o r u , a n d Goto S a c h i k o , N i p p o n Kagaku R y o k o g a k u k a i Z a s s h i , 1 7 , 9 7 9 ( 1 9 6 9 ) : C . A . -972 10247m ( 1 9 7 0 ) . a n d S c h w a r t z , M . A . , J. Pharm. K i n g e t , R.D. S c i . , 58, 1 1 0 2 ( 1 9 6 9 ) . HOU, J . P . a n d P o o l e , J . W . , J . Pharm. S c i . , 58, 1510 ( 1 9 6 9 ) . and Kaplan, Granatek, A.P., Granatek, E.S. M.A., G e r . O f f e n . 2 , 1 0 5 , 0 4 6 , A u g u s t 1 9 7 1 : C . A . -77 5 121388g ( 1 9 7 1 ) . Kuchinskas, E . J . and Levy, G . N . , J.Pharm. S c i .6 1 , 727 ( 1 9 7 2 ) . Weiss, P . J . and Palmer, R . V . , A n t i m c i r o b , 1 9 6 4 355-9 9 A q e n t s Chemother, (Publ, 1965) N i e b e r g a l l , P. J . , H u s s a r , D . A . , Gressman, W.A., S u g i t a , E.T. and D o l u i s i o , J . T . , J. Pharm. P h a r m a c o L , 18, 7 2 9 ( 1 9 6 6 ) . Cressman, W . A . , S u g i t a , E.T., D o l u i s i o , J . T . 801 (1966). and N i e b e r g a l l , P . J . , I b i d . Cressman, W . A . , S u g i t a , E . T . , D o l u i s i 0 , J . T . a n d N i e b e r g a l l , P . J . , J . P h a r m . S c i . , 58, 1471 (1969). Nara T a k a s h i ; M j sawa, Masanaru:and O k a c h i , Ryo, G e n . O f f e n . 1 , 9 4 5 , 6 9 7 , A u g u s t 1 9 7 0 : C . A . 3,99384w ( 1 9 7 0 ) . Kaufman, W. a n d B a u e r , K . , U . S . 3 , 0 7 9 , 3 0 7 , F e b r u a r y 26,1963;C.A.=, 13093h ( 1 9 6 3 ) .
-
.
91.
92.
18,
93.
94.
95.
52
AMPICILLIN
96.
97. 98. 99. 100. 101.
102.
103. 104.
105.
106. 107.
108.
109.
110.
111.
K a u f m a n , W . , In+-, C o n q r . C h e m o t h e r . P r o c . , 3 r d , S t u t t g a r t , 1 9 6 3 , 2 , 1248-50 ( 1 9 6 3 ) ( P u b . 1 9 6 4 ) ; C . A . -96 5 19016h ( 1 9 6 6 ) . C o l e , M . , B i o c h e m . J. 1969, 115 (4),747-56. C o l e , M . , I b i d . , 1 9 6 9 , 1 1 5 ( 4 ) , 757-64. W o l m a n , Y . , I s r . J. C h e m . 2, 231 ( 1 9 6 7 ) : C . A . 6 8 , 6 9 3 1 5 ~( 1 9 6 8 ) . C i e s l a k , J . a n d W a s i l i e w a , B., Pol. 5 1 , 7 0 8 , A u g u s t 2 4 , 1 9 6 6 ; C . A . 6 8 , 2 9 0 0 ~( 1 9 6 8 ) . A l b u r n , H . F . , G r a n t , N.H and F l e t c h e r , H . , F r . 1 , 3 4 9 , 6 2 1 , J a n u a r y 1 7 , 1 9 6 4 : C . A . 60, 106883. ( 1 9 6 4 ) A l b u r n , H.E., G r a n t , N . H . a n d F l e t c h e r , H . , U . S . 3 , 2 0 6 , 4 5 5 , S e p t e m b e r 1 4 , 1 9 6 5 : C . A . -96 4 3547b ( 1 9 6 6 ) . C a t l i n , E . R . a n d M e h t a , M.D., B r i t . 9 0 3 , 7 8 5 , A u g u s t 22, 1962: C . A . 5 8 , 1466a ( 1 9 6 3 ) . C i e s l a k , J . , V a s i l e v a , B . , B u s k o , I. and S i e r a n k i e w i c z , J . , A c t a Pol. P h a r m . 1 9 6 8 . 7 0 , 57722m ( 1 9 6 9 ) . 25 ( 3 ) 263-7; C . A . N o v a k , L . , K o e n i g , J. a n d R u d i n g e r , J . , C z e c h . 1 2 4 , 8 3 6 , O c t o b e r 1 5 , 1 9 6 7 : C . A . -96 9 96706h ( 1 9 6 8 ) . E k s t r o m , B. a n d S j o b e r g , B . , A c t a C h e m . Scand. 19, 1245 ( 1 9 6 5 ) . B i a n c h i , G. a n d Z a n n i n i , E . , S . A f r i c a n 6 8 0 0 , 2 9 4 , J u l y 9 , 1968: C . A . 70 7 7 9 5 5 t (1969). A l b u r n , H . E . , C l a r k , D . E . a n d G r a n t , N.H., U.S. 3 , 5 2 0 , 8 7 6 , J u l y 2 1 , 1 9 7 0 : C . A . -’ 73 66568e ( 1 9 7 0 ) . A m e r i c a n Home P r o d u c t s C o r p . , B r i t . 1 , 0 8 2 , 427, September 6 , 1 9 6 7 : C . A . 68, 95808k (1968). A u s t i n , K.W.B. a n d Bird, A . E . , S . A f r i c a n 6705,,627 February 27,1968; C . A . 70 474381 ( 1 9 6 9 ) . K o n i g , R . , Hung. 155,099, S e p t e m b e r 25,1963; C . A . 70, 4 7 4 4 1 e ( 1 9 6 9 ) . 53
EUGENE IVASHKIV
1 1 2 . Mestre, R . , S p a n . 3 5 5 , 3 6 1 , November 1 6 , 1 9 6 9 ; C . A . 72, 1 0 0 6 8 6 h ( 1 9 7 0 ) . 1 1 3 . Beecham G r o u p L t d . , Neth. A p p l . 6 , 6 0 3 , 0 4 4 , 6 6 , 28763m ( 1 9 6 7 ) . September 19, 1966; C.A. 114. L e p e t i t S.p.A., Belg. 622,901, J a n u a r y 15, 1963; C.A. 5 8 , 7534d ( 1 9 6 3 ) . 1 1 5 . Novo T e r a p e u t i s k L a b o r a t o r i u m A / s . , Brit. 9 8 5 , 6 5 5 , March 10, 1 9 6 5 ; C . A . 6 2 , 1 5 3 (1965). 116. Doyle, F . P . , F o s k e r , G . R . , N a y l e r , J . H . an d S m i t h H., J.Chem. S O C . 1 9 6 2 , 1 4 4 0 . 117. F o s k e r , G . R . , N a y l e r , J . H . C . an d W i l c o x , J . A . , B r i t . 9 9 1 , 5 8 6 , May 1 2 , 1 9 6 5 : C . A . 62 8368f ( 1 9 6 5 ) . 118. F o s k e r , G.R., N a y l e r , J . H . C . a n d W i l c o x , J . A . , U . S . 3,316,247, A p r i l 25, 1967. 119. Fosker, G . R . , Nayler, J . H . C . a n d Wilcox, J . A . , U.S. 3 , 3 2 5 , 4 7 9 , J u n e 1 3 , 1 9 7 6 . and Weichet, J . , Belg. 626,175, 1 2 0 . Novak, L . December 2 , 1 9 6 3 ; C . A . 61, 1 4 6 7 9 e ( 1 9 6 4 ) . 121. Chas. P f i z e r & C o . , I n c . , B r i t . 9 5 8 , 8 2 4 , May 2 7 , 1 9 6 4 ; C . A . 61, 4 3 6 1 g ( 1 9 6 4 ) . 1 2 2 . Doyle, F . P . , N a y l e r , J . H . C . and S m i t h , H . , B r i t . 8 7 3 , 0 4 9 , J u l y 1 9 , 1 9 6 1 ; C . A . 57, 7279b ( 1 9 6 2 ) . 1 2 3 . Dane, E . a n d D o c k n e r , J . , Angew. Chem. 76 ( 8 ) , 342 ( 1 9 6 4 ) . 1 2 4 . Dane, E. a n d D o c k n e r , T . , C h e m . B e r . 98 ( 3 ) , 789 ( 1 9 6 5 ) . 125. Fosher, G . R . and Nayler,J.H.c. , B r i t . 980,777, J a n u a r y 2 0 , 1 9 6 5 ; C . A . 63, 1 3 , 2 7 0 h ( 1 9 6 5 ) . 126. Smith, K l i n e and French L a b o r a t o r i e s , U.S. 3 , 1 1 7 , 1 1 9 , J a n u a r y 7 , 1 9 6 4 ; C . A . 61, 663h ( 1 9 6 4 ) . 127, U g l e s i c , A. and S e i w e r t h , R . , G e r . Offen. 1 , 9 4 0 , 5 7 1 , F e b r u a r y 1 9 , 1 9 7 0 : C . A . 72, 90451m ( 1 9 7 0 ) . s m i t h , H. a n d 1 2 8 . Doyle, F.P., N a y l e r , J . H . C . , S t o v e , E. R . , N a t u r e 191, 1 0 9 1 ( 1 9 6 1 ) . 54
AMPICILLIN
129. Luttinger, J . R . , Lein, J. and Gourevitch, A. Belg. 612,599, April 30, 1962: C.A. -958 0083f (1963). 130. Dursch, F., The Squibb Institute for Medical Research, Private Communication, September 1 1967. 131. Mestre, J.R., Span. 291,104, September 10, 1963; C.A. 61, 1869g (1964). 132. Ekstrom, B., Gromez-Revilla, A,, Mollberg,R. Thelin, H. and Sjoberg, B., Acta Chem. Scand. 19 281 (1965). 133. Sjoberg7B.O.H. and Ekstrom, B.A., Brit. 940,489,October 30, 1963: C.A. 61, 2941111 (1964). 134. Sjoberg, B.O.H. and Ekstrom, B.A., Belg. 620,519, November 14, 1962: C.A.58, 11501h (1963). 135. Johnson, D.A. and Wolfe, S., U.S.3,140,282, July 7 , 1964: C.A. 61, 8315c (1964). 136. Robinson, Ch. A. Ger. Offen. 1,960,748, July 2, 1960: C.A. 73, 45504r (1970). 137. Soulal, M.J., Brit. 975,379, November 18, 1964: C.A. 6 2 , 3890f (1965). 138. Beecham, Group Ltd. , Fr. 1,365,220, June 1964: C.A. 61, 13316f (1964). 139. Bohme, E. and Dolfini,, J.E.,The Squibb Institute for Medical Research, Privatc C3mmunication. February 17, 1969. 140. Anon. Ind. - Cher. 39 (lo), 513 (1963). 141. Farbenfab: Bayer, Brit. 986,904,March 24, 1965. 142. Farbenfab: Bayer, Ger. Offen. 1143516, August 22, 1963. 143. Koenig, H.B. and Risse, K.H., Belq. 636,975, March, 1964: C.A. 62, 8947c (1965). 144. Koenig, H.B., Ger. 1,178,434, September 1964: C.A. 61, 14476g (1964). 145. Feinberg, J.G. and Weston, R.D., Brit. 1,131,741, October 1968: C.A. 70, 14410r ~
EUGENE I V A S H K I V
(1969). 146. Dewdney, J . , H a t t , B.W. and S m i t h , H . , 2. A f r i c a n 6,803,094 O c t o b e r 1968: C . A . 71, 6526p (1969). 147. Beecham Group L t d . , F r . 1,526,417,May 1968: C . A . 71, 33414g (1969). 148. S a v i t s k y a , E.M., Nys, P . S . a n d B u l y c h e v a , M.S., Khim.-Farm. Sh. 1969, 3(7), 32-8. 149. J o h n s o n , D . A . a n d H a r d c a s t l e , G . A . , U.S. 3,271,389,S e p t e m b e r 1966: C . A . 66, 10930m (1967). 150. S a c c a n i , F., N e r i , C . a n d S u d a n o , F . , B o l l . Chim. Farm. 1969, 108 (12), 777-80: C . A . 72, 136464~(1970). 151. Modin, R. a n d S c h r o d e r - N i e l s e n , M . , A c t a Pharm. S u e c i c a 1971, 8_(6), 573-84. 152. A t w a l , M.S. a n d S h i p k o w s k i , E . R . , The Squi3b I n s t i t u t e f o r Medical Research, P r i v a t e Communication, 1969. 153. C o c l e r s , L . , D e l a h a n t , R. a n d V e r s o l a t o , A . , J . Pharm. B e l g . 24, 475 (1969). 154. L i g h t b o w n , J . W . , a n d D e R o s s i , P . , A n a l y s t
90, 89 (1965). 155. Thomas, A . H . a n d B r o a d b r i d g e , R . A . , A n a l y s t 95, 459 (1970). 156. Zuidweg, M . H . J . , o o s t e n d o r p , J . G . a n d BOS, C.J.K., J. C h r o m a t o g r . 42,552 (1969). 157. Wayland, L . G . a n d W e i s s , P . J . , J . P h a r m . S c i . 57, 806 (1968). 158. M c G i l v e r a y , I . J . and S t r i c k l a n d , R . D . , J . P h a r m . S c i . , 56, 77 (1967). 159. H e l l b e r g , H., J. A s s o c . of A n a l . Chem., 51, 552 (1968). 160. Weiss, P . J . , T a l i a f e r r o , B . , H u c k i n s , R. and C h a s t o n a y , R . , I b i d . 50, 1294 (1967). 161. B i a g i , G . L . , B a r b o r o , A . M . , Gamba, M.F. a n d G u e r r a , M. C . ,
J. C h r o m a t o g r . 4 1 ,
371 (1969). 162. S a c c a n i , F . ,
Boll. Chim. Farm. 56
106, 625
AMPICILLIN
(1967). 163. Wanq J e n T s e , Chou Hsun, H s i u L i n . Chun H u i a n d Chen KO S h e n q , Tai-Wan K ' o H s u e h 2 4 , 19 (1970); C . A . 74, 115942h (1971). 164. G o o d a l l , R . R . a n d L e v i , A . A . , A n a l y s t -772 277 (1947). 165. G l i s t e r , G . A . a n d G r a i n e r , A . , I b i d . 75, 310 (1950). 166. B a k e r , P . B . , D o b s o n , F. a n d M a r t i n , A . J . P . , I b i d . 75, 651 (1950). 167. S t e p h e n s , I . a n d G r a i n e r , A . , J . Pharm. Pharmacol.. 1,702 (1955). 168. Thomas, R., N a t u r e 191, 1161 (1961). 169. T u t t , D . E . a n d S c h w a r t z , M . A . , A n a l . Chem. 4 3 . 338 (1971). 170. S m i t h , J . W . G . , d e G r e y , G . E . a n d P a t e l , U . J A n a l y s t 92, 247 (1967). 171, A n g e l u c c i , L. a n d B a l d i e r i , M . , J , Pharm. P h a r m a c o l . 23, 471 (1971). 172. B u r y a k , V . P . a n d K u r i u n a y a , N . V . , F a r m . Z h , 25, 42 (1970); C . A . 74 6412h (1971). 173. D o a d r i o , A . a n d G a r c i a - M i r a s i e r r a Gomez,M., A n , R. Acad. Farm. 35, 115 (1969); C . A . -971 42363s (1969). 174. R a s m u s s e n , C . E . a n d H i g u c h i , T . , J . P h a r m . S c i . 60 1608 (1971). 175. L e p i d i , A . A . a n d N u t i , M . P . , M y c o p a t h o l . Mycol. Appl. 43, 11 (1971); C . A . 74, 146307e (1971). 176. J u s c o , W . J . , J . Pharm. S c i . , 60, 728 (1971). 177. S i n s h e i m e r , J . E . , Hong, D . D . a n d 58, 104 Burckhalter, J . H . , J.Pharm.Sci., (1969). 178. P r i n c e t o n A p p l i e d R e s e a r c h , A p p l i c a t i o n -7
-9
~
Note, AN-111.
179. T a k e o Murakawa, Y o s h i m i , W a k a i , M i n o r u N i s h i d a , R y o c h i F u j i i , M a s a t o s h i Konno, Kazuko O k a d a , S a s h i k o G o t o a n d S h o q o K u w a h a r a , J . A n t i b i o t . 2 3 , 250 (1970).
57
EUGENE IVASHKIV
180. Nishida Minoru, Murakawa Takeo, Goto Sashiko, Fujii Ryochi, Konno Masatoshi and Okada Kazuko, Nippon Kaqaku Ryooqakuai Zasshi, l7, 1973 (1969); C.A. 73, 12731j (1970). 181. Fujii Ryochi, Kondo Masatoshi, Okada Kazuko, Kumagai Michikiko, Yoshida Akio and Matsuzaki Meiki; Nippon Koqoku Ryoogakuai Zasshi, l.7, 1920 (1969); C.A. 72, 77097f (1970). 182. Sacconi, F., Boll. Chim. Farm., 106,625 (1967): C.A. 6 8 , 24523c (1968). 183. Biagi, G.L., Barbaro, A.M., Gamba M.F. and Guerra, M C., J. Chromatogr. 41, 371 (1969). 184. Biagi, G.L., Barbaro, A.M. and Guerra, M.C., J. Chromatogr., 51, 548 (1970). 185. Roberts, H., The Squibb Institute for Medical Research, Private Communication, 1972. 186. Pan, S.C., The Squibb Institute €or Medical Research, Private Communication, 1969. 187. Roberts, H.R. and Vahidi, A., The Squibb Institute for Medical Research, Private Communication, 1971. 188. Smith, J.T. and Hamilton-Miller, J.M.T., Chemotherapy l5, 368 (1970). 189. Hill, A. and Zaleski, W.A., N.Eng. J. Med., 283, 490 (1970). 190. Uri, J., Naturwissenschaften 52, 354 (1965). 191. Alicino, J., Ana1.Chem. 18,619 (1946). 192. Russo-Alesi, F.M., The Squibb Institute for Medic a 1 Research , Private Commun ica tion, 1970. 193. Bomstein, J., Evans, W.G. and Shepp, J.M., Ann. N.Y. Acad. Sci., 130, 589 (1965) 194. Boxer, G. and Everett, P., Ana1.Chem. -921 670 (1949). 195. Henstock, H., Nature, 164, 139 (1949). 196. Fed. Register 33, 4099, March 1968. 197. Niedermayer, A.O., Russo-Alesi, F.M. and 58
AMPICILLIN
L e n d z i a n , C . A . , A n a l . Chem. 32, 664 (1960). 198. G r a f n e t t e r o v a , J . , C l i n . Chim. A c t a , 11, 128 (1965). 199. F e d . R e q i s t e r 33 (165), 11991-7, A u g u s t 23, 1968. 200. Y a k o v l e v , V.P. a n d S k a l a , L . Z . , A n t i b i o t i k i , 11, 723 (1966): C . A . 6 5 , 17535f (1966).
201.
202. 203. 204. 205.
Shaw, W . H . C .
a n d Duncombe, R . E . ,
Analyst,
88, 694 (1963). J o n e s , A. a n d P a l m e r , G . , A n a l y s t , 95, 463 (1970). D e w a r t , R., N a u d t s , F. a n d L h o e s t , W . , Ann. N . Y . Acad. S c i . 130, 647 (1965). G r i m s h a w , J . J. a n d Jones, A . , A n a l y s t 95, 466 (1970). P l a t t , T.B., G e n t i l e , J , a n d G e o r g e , M . J . , Ann. N . Y . Acad. S c i . 130, 664 (1965).
206. O u i n n , E . L . ,
Colville, J.M., B a l l a r d , L., a n d Debnam, F . , A n t i m i c r o b . A g e n t s
J o n e s , D. C h e m o t h e r . 1962, 339 (1963). 207. R o b i n s o n , G . N . a n d S t e v e n s , S . ,
11
Br1t.Med.J.
191 (1961). 208. P e r e n y i , T., B i r o , L. a n d A r r , M . , K i s e r l . O r v o s t u d . , 2 2 , 251 (1970): C . A . 73, 968212 (1970). 209. Murakawa T a k e o , W a k a i Y o s h i m i , T o i Y a s u k o and Nashida Minoru, J a p . J . A n t i b i o t . , 22, 387 (1969): C . A . ->72 119723g (1970). 210. B i a g i , G . L . , A n t i b i o t i c a , (Roma) 5, 198 (1967): C . A . 69, 7 5 5 5 1 ~(1968). 211. R o b i n s o n , G . N . a n d S u t h e r l a n d , R . , B r i t . J. P h a r m a c o l . , 25, 638 (1965). 212. S c h o l t a n , W . , 1nt.Cong.Chemother.Proc. G, S t u t t g a r t , 1963, 251 (1964). 213. A c r e d , P., Brown, D . M . , H a r d y , T . L . a n d M a n s f o r d , K . R . L . , N a t u r e 199, 758 (1963). 214. T a k e o Murakawa, Y o s h i m i Wakai a n d M i n o r u N i s h i d a , J . A n t i b i o t . , 23, 481 (1970). 215. Bond, J . M . , P o s t g r a d . Med. J . , S u p p l . 40, -9
59
EUGENE IVASHKIV
17-20 (1964). 216. H i d e o H i n o i , H i r o s h i m a D a i q a k u I g a k u Z a s s h i , 13, 637 (1965): C . A . 65, 2847c (1966). 217. H i d e o H i n o i , I b i d 1 3 . 601 (1965): C . A . 65, 284621 (1966). 218. K u n i n , C . M . , C l i n . P h a r m a c o 1 . T h e r . 166 (1966). 219. S c h o l t a n , W. a n d S c h m i d t , J . , A r z n e i m i t t e l Forschung l . 2 , 741 (1962); C . A . 5 7 , 15751i (1962). 220. Osamu K i t a m a t o a n d I t t a F u k a y a , J . A n t i b i o t . Ser. B, 16, 109 (1963). 221. K u n i n , C . M . , J . L a b . C l i n . M e d . , 65, 406(1965), 222. L e g r e r , F. , A r z n e i m i t t e l - F o r s c h u n g , l6, 814 (1966): C . A . 6 5 , 15959e (1966). 223. K u n i n , C . M . , Ann. N . Y . Acad. S c i . 145, 282 (1967). 224. K u n i n , C . M . , A n t i m i c r o b . A q e n t s C h e m o t h e r . 1965, 1025-34. 225. K u n i n , C . M . , P r o c . S o c . E x p . B i o 1 . M e d . 117, 69 (1964). 226. Y o s h i k i k o H o r i u c h i a n d K o j i S h i b a t a , A r c h . A l l e r g y A p p l . Immunol. 28,306 (1965). 227. K o j i S h i b a t a , A r e r u g i 15,97 (1966,); C . A . 6 4 , 18202h (1966). 228. D o l u i s i o , J . T . , L a P i a n a , J . C . a n d D i t t e r t , L . W . , J . P h a r m . S c i . , 6 0 , 715 (1971). 229. K l e i n , J.O., F i n l a n d , M. a n d Wilcox, C . , Am. J . Med. S c i . , 245, 544 (1963) 230. Bunn, P.A. , A n t i m i c r o b . A g e n t s C h e m o t h e r . 1961, 739 (1962). 231. Bunn, P . A . , O ' B r i e n , J. B e n t l e y , D. a n d Haymen, H . , I b i d , 1962 323 (1963). 232. K l e i n , J.O., F i n l a n d , M. a n d W i l c o x , C . , Am. J. Med. S c i . , 245, 544 (1963). 233. C h r i s t i e , A . B . , B r i t . Med. J . , I , 1609 (1964). 234. M a c G r e g o r , G . A . , L a n c e t 11, 993 (1962).
z,
x.
60
AMPICILLIN
235. M u n n i c h , D., U r i , J . a n d V a l u , G . , C h e m o t h e r a p i a , g , 226 (1964). 236. K n u d s e n , E.T., R o l i n s o n , G . N . a n d S t e v e n s , S . , B r i t . Med. J., 11, 198 (1961). 237. K l e i n , J . O . , F i n l a n d , M. a n d Wilcox, C . , Am. J . Med. S c i . 245, 5 4 4 (1963). 238. Bunn, P . A . , A n t i m i c r o b . A g e n t s C h e m o t h e r . 1962 323 (1963). 239. S t e w a r t , G . T . , C o l e s , H . M . T . , N i x o n , H . H . a n d H o l t , R . J . , B r i t . Med. J. 11, 200 (1961)
61
This Page Intentionally Left Blank
CHLORPROTHIXENE
Bruce C. Rudy and Bernard Z. Senkowski
63
6. C. RUDY AND
B. Z . SENKOWSKI
INDEX Analytical P r o f i l e - Chlorprothixene
1.
Description 1.1 Name , Formula, Molecular Weight 1.2 Appearance, Color, Odor 1.3 Isomeric Forms Phys i c a l P r o p e r t i e s 2.1 I n f r a r e d Spectrum 2.2 Nuclear Magnetic Resonance Spectrum 2.3 U l t r a v i o l e t Spectrum 2.4 Fluorescence Spectrum 2.5 Mass Spectrum 2.6 Optical Rotation 2.7 Melting Range 2.8 D i f f e r e n t i a l Scanning Calorimetry 2.9 Thermogravimetric Analysis 2.10 S o l u b i l i t y 2 . 1 1 X-ray C r y s t a l P r o p e r t i e s 2 . 1 2 D i s s o c i a t i o n Constant
3.
Synthesis
4.
S t a b i l i t y Degradation
5.
Drug Metabolic Products
6.
Methods o f Analysis 6.1 Elemental A n a l y s i s 6.2 Phase S o l u b i l i t y Analysis 6.3 Thin Layer Chromatographic Analysis 6.4 D i r e c t S p e c t r o p h o t o m e t r i c Analysis 6.5 Colorimetric Analysis 6.6 Fluorescence Analysis 6.7 Non-Aqueous T i t r a t i o n
7.
Acknowledgements
8.
References
64
CHLORPROTHIXENE
1.
Description
Name, Formula, Mol ecul ar Weight C h l o r p r o t h i x e n e i s 2-chloro-N,N-dirnethylt h io x a n th e n e - A9 , Y - p r o p y l a m i n e . 1.1
CHCH, CH2N(CH&
&fC' C18H18ClNS
M o l e c u l a r Weight:
315.87
Appearance, C o l o r , Odor C h l o r p r o t h i x e n e i s a l i g h t yel l ow t o yel l ow c r y s t a l l i n e powder w i t h a l i g h t a m i n e - l i k e o d o r . 1.2
I s o m e r i c Forms Chlorprothixene e x i s t s as a cis- o r a t r a n s i s o m e r . The c i s - i s o m e r h a s a l s o been r e f e r r e d t o as t h e a - i s o m e r o r t F h i g h m e l t i n g i s o m e r ( 1 , Z ) . The t r a n s - i s o m e r l i k e w i s e has been r e f e r r e d t o a s t h e B-isomer o r low m e l t i n g i s o m e r . T h i s work w i l l d e a l p r i m a r i l y w i t h t h e a - i s o m e r . 1.3
3 -.
Phys i c a l P r o p e r t i e s
I n f r a r e d Spectrum The i n f r a r e d s pect r um o f bul k r e f e r e n c e s t a n d a r d c h l o r p r o t l i ~ x e n ei s shown i n F i g u r e 1 ( 3 ) . The spect rum o f a 10'" car b o n d i s u l f i d e s o l u t i o n o f c l i l o r p r o t h i x e n e ( w / v ) was measured v e r s u s car bon d i s u l f i d e i n 0 . 1 mm NaCl l i q u i d c e l l s on a P e r k i n Elmer 621 S p e c t r o p h o t o m e t e r . 2.1
The f o l l o w i n g a s s i g n m e n t s have been g i v e n t o t h e bands i n F i g u r e 1 ( 3 ) : a . C h a r a c t e r i s t i c f o r a r o m a t i c CH: 3063 cm-l b . C h a r a c t e r i s t i c f o r CH2 s t r e t c h i n g : 2939 and 2854
cmc.
'
C h a r a c t e r i s t i c f o r CHI, s t r e t c h i n g : -7816 and 2767 cm65
B. C. RUDY
i
-i
A N D B. 2. SENKOWSKI
33NVUIHSNWl K
66
0
8 0
0 0 0
9 0
e N
8 0
8
N
8 8 8 Y)
*)
*
CH LORPROTH I XE NE
d.
e.
C h a r a c t e r i s t i c f o r 4 f r e e H on benzene r i n g : 757 t o 739 cm-l C h a r a c t e r i s t i c f o r 2 f r e e H on benzene r i n g : 809 cm-l
2.2
N u c l e a r Magnetic Resonance Spectrum (NMR) The NMR s p e c t r u m shown i n F i g u r e 2 was o b t a i n e d by d i s s o l v i n g 5 2 . 2 mg o f r e f e r e n c e s t a n d a r d c h l o r p r o t h i x e n e i n 0 . 5 m l o f C D C 1 3 c o n t a i n i n g t e t r a m e t h y l s i l a n e as t h e i n t e r n a l reference. The s p e c t r a l a s s i g n m e n t s are shown i n Table I ( 4 ) .
TABLE I NMR S p e c t r a l Assignments f o r C h l o r p r o t h i x e n e
Type P r o t o n s
No. o f Each Proton
Chemical S h i f t (ppm)
methyl methy 1e n e vinyl aromatic
6 4 1 7
2. 24 2.35-2.80 5.97 7.10-7.60
-
Multiplicity S
m (u) t (u) m (u)
s = s i n g l e t ; m(u) uns ym m et r i cal m u l t i p l e t ; t ( u ) = uns y mme tr ical t r i p l e t 2.3
U l t r a v i o l e t Spectrum The u l t r a v i o l e t s p e c t r u m o f c h l o r p r o t h i x e n e i n 0.1N HC1 i n t h e r e g i o n 400 t o 210 nm e x h i b i t s t h r e e maxima and t h r e e minima. The maxima a r e l o c a t e d a t 229 - 230 nm ( E = 3 . 4 x l o 4 ) , 267 - 268 nm ( E = 1 . 3 x l o 4 ) , and 323 - 324 nm (E = 2 . 8 x l o 3 ) . The minima were o b s e r v e d a t 217 nm, 254 nm, and 307 - 308 nm. The spect rum p r e s e n t e d i n F i g u r e 3 was o b t a i n e d from a r e f e r e n c e s t a n d a r d s o l u t i o n o f c h l o r p r o t h i x e n e a t a c o n c e n t r a t i o n o f 0. 602 mg p e r 100 m l o f 0.1N H C 1 ( 3 ) . 2.4
F l u o r e s c e n c e Spectrum F i g u r e 4 shows t h e e x c i t a t i o n and e m i s s i o n s p e c t r a €or r e f e r e n c e s t a n d a r d c h l o r p r o t h i x e n e from 260 t o 540 nm ( 5 ) . The s p e c t r a were measured on a 0.1N HC1 s o l u t i o n o f c h l o r p r o t h i x e n e ( 0 . 5 mg/ml) u s i n g a Farand M K - 1 s p e c t r o f l u o r o m e t e r . E x c i t a t i o n a t e i t h e r 310 nm o r 352 nm produced 67
6.C. R U D Y A N D 6. Z . SENKOWSKI
68
CHLORPROTHIXENE
Figure 3 Ultraviolet Spectrum of Chlorprothixene
1.0
.8
.6
NANOMETERS
B. C. RUDY AND B. Z . SENKOWSKI
AlISN31NI
CHLORPROTHIXENE
i d e n t c a l emission s p e c t r a with a max m u m a t 401 nm. 2 5
Mass Spectrum The mass spectrum o f c h l o r p r o t h i x e n e r e f e r e n c e s t a n d a r d was o b t a i n e d u s i n g a CEC 21-110 s p e c t r o m e t e r w i t h an i o n i z i n g energy o f 70 eV (Figure 5) ( 6 ) . The low r e s o l u t i o n spectrum showed t h e f o l l o w i n g d i a g n o s t i c p e a k s : Intensity
mass (m/e) 315 313 271 257 255 2 34 221 189 58
v e r y weak v e r y weak v e r y weak weak medium - we ak weak strong medium-weak very strong
The m o l e c u l a r i o n a t m/e 315 and t h e fragment i o n s a t m/e 2 7 1 , 257, and 255 d i s p l a y t h e expected c h l o r i n e i s o t o p e peak 2 mass u n i t s h i g h e r . The b a s e peak a t m/e 58 and t h e i o n a t m/e 257 a r e both due t o c l e a v a g e b e t a t o t h e amine f u n c t i o n . The peak a t m/e 255 could be e x p l a i n e d as l o s s o f two hydrogens from m/e 257 p o s s i b l y l e a d i n g t o a r i n g - c l o s e d s t r u c t u r e . The peak a t m/e 2 2 1 i s due t o t h e l o s s o f H C 1 from m/e 257. S i n c e t h e s p e c t r a d i d n o t show any change w i t h time i t i s l i k e l y t h a t m/e 313 i s a fragment i o n d e r i v e d from m/e 315. Again, a r i n g c l o s u r e type of s t r u c t u r e i s a p o s s i b i l t y (6). 2.6
Optical Rotation C h l o r p r o t h i x e n e e x h i b i t s no o p t i c a l a c t i v i t y .
Melting Range A s h a r p m e l t i n g p o i n t i s n o t observed w i t h c h l o r p r o t h i x e n e . ' The m e l t i n g depends on t h e r a t e o f h e a t i n g . The m e l t i n g range r e p o r t e d i n NF XI11 i s 96.5' 101.5°c. 2.7
71
to
6.
C. RUDY AND 6.2. SENKOWSKI
72
CH LORPROTH I XENE
2.8
D i f f e r e n t i a l Scanni ng C a l o r i m e t r y (DSC) The DSC c u r v e €or r e f e r e n c e s t a n d a r d c h l o r p r o t h i x e n e was o b t a i n e d u s i n g a P e r k i n Elmer DSC - IB C a l o r i m e t e r . With a t e m p e r a t u r e program o f 10°C/min., a m e l t i n g endotherm was o b s e r v e d s t a r t i n g a t 92.8OC (shown i n F i g u r e 6 ) and a n o t h e r endotherm s t a r t i n g a t 246OC which c o r r e s p o n d s t o t h e decom pos i t i on o f t h e c h l o r p r o t h i x e n e . The Aldf was found t o be 7 . 4 kcal / m ol e f o r t h e m e l t i n g endot h er m ( 7 ) . 2.9
Th e r m ogr avi m et r i c A n a l y s i s (TGA) The TGA performed on r e f e r e n c e s t a n d a r d c h l o r p r o t h i x e n e e x h i b i t e d n o l o s s o f w ei ght when h e a t e d t o 1 0 S O c a t a h e a t i n g r a t e o f 10°C/min ( 7 ) . Solubility The s o l u b i l i t y d a t a o b t a i n e d a t 2 5 O C f o r reference standard chlorprothixene is l i s t e d i n Table I1 (8). 2.10
TABLE I 1
Ch 1o r p r o t h i x e n e
- So l u b i 1i t y
Solvent 3A a l c o h o l benzene ch 1o r 0 f o rm 95% e t h a n o l ethyl ether i sop ropano 1 me t h a n o 1 petroleum e t h e r (3Oo-6O0) water 2.11
So 1u b i 1i t y (mg/ml )
36.7 30.5 >SO0 28.2 77.6 22.0 36.5 16.9 1000
114 99
155
138
380 c a . 330
137 99
525 500
137 114
11.6 44.4
114
39.2
137 137
33.0 Sparingly soluble Sparingly soluble Sparingly soluble Sparingly soluble
137 114 114
114 114
JOHN E. FAIRBROTHER
2.54 Solvent ---
Tempereture
---Tor---
Olive O i l Olive O i l C a s t o r Oil Corn O i l Liquid Pzraf f i r ) Tu r p e n t i ri e 2.4
S o l u b i l i t y i n O i l s of Pharmaceutical Interest
R O O K Temp. 25
25 25 25 Room Temp.
Pkiysi cal
R ef e-_r e n c e S o l u b i l i-t y __ ( mg c h l o r a l hydrate per m l solvent) ca.
10 14 0
114 137 137
990
137
710
8 30 13.3 Sparingly soluble
$37 114
P r o p e r t i e s of Solutions
a n d Melts 2.41
H e a t s o f S o l u t i on a n d D i l -ution
The h e a t of s o l u t i o n o f c h l o r a l h y d r a t e i r m e t h a n o l Pas b e e n d e t e r n l i n c > d mlcrc,cal o r i m e t ri c a l l y a s a b o u t - 1 . 1 2 K c a l / m o l . l o . S c h i 1 1 9 4 m e a s u r e d t h e t e n p e r a t u r e r i s e o n d i s s o l u t i o n of c h i o r a l arid m e l t e d c h l o r a l h y d r a t e i n w a t e r . In t h e same p a p e r , h e d e s c r i b e s t h e t e m p e r a t c u r e c h a n g e o b s e r v e d on d l s s o l v i n g c h l o r a l h y d r a t e i n w a t e r , a n d c o n p a r e s i t w i t h t h o s e p r o d u c e d by c h l o r a l hemihydrate (see s e c t i o n 2 . 2 ) and by c h l o r a l h y d r a t e melts t h a t had been r a p i d l y c o o l e d t o rcom t e m p e r a t u r e i m m e d i a t e l y G e f c r e dissolution. Schi11g4 suggests t h a t i n a m e l t c f c h l o r a l hydrate s e v e r a l hydrates of d i f f e r e n t s t r u c t u r e s may e x i s t . By c a l c u l a t i o n f r o m S c h i l l ' s f i g u r e s , an approx. heat o f s o l u t i o n f o r c h l o r a l h y d r a t e i r water i s - 0 . 7 8 K c a l / r r , o l . Measurements o f t h e h e a t o f d i l u t i o n o f c h l o r s l h y d r a t e a q u e o u s s o l u t i o n s h a v e b e e n made95. No N e r r s t t e m p e r a t w e c o e f f i c i e n t , i s fourid for these solutions.
104
CHLORAL HYDRATE
2.42
D i s s o c i a t i o n a n d pH
The d i s s o c i a t i o n o f c h l o r a l h y d r a t e i n cyclohexane has a l r e a d y been mentioned i n s e c t i o n 2.13. D i s s o c i a t i o n of d i l u t e aqueous s o l u t i o n s c h l o r a l h y d r a t e was r e p o r t e d i n t h e same p a p e r
yg
T h e i o n i z a t i o n c o n s t a n t , pKa, was o b t a i n e d by m e a s u r i n g t h e pH o f b u f f e r e d s o l u t i o n s o f c h l o r a l h y d r a t e g 6 . T h e mean o f 25 e x p e r i m e n t s g a v e pKa 1 0 . 0 4 , which d i f f e r s c o n s i d e r a b l y f r o m t h e v a l u e o f 11 o b t a i n e d b y E u l e r a n d E u l e r 9 7 a n d i s c l o s e r t o pK 9.77, derived i E d i r e c t l y from k i n e t i c rneasurernents98,
The d i s s o c i a t i o n o f c h l o r a l h y d r a t e i n v a r i o u s o r g a n i c s o l v e n t s (CCl4, b e n z e n e e t c . ) has been s t u d i e d by i n f r a r e d spectroscopy7 (see section 2.11). Studies of t h e near i n f r a r e d s p e c t r a 6 have a l s o been used t o c a l c u l a t e e q u i l i b r i u m and r a t e c o n s t a n t s f o r t h e d i s s o c i a t i o n o f s o l u t i o n s of c h l o r a l h y d r a t e .
2.43
Surface -___--
Tension
Teitel'baum e t a1.lo0 give a complete picture of the surface tensions obtained with aqueous s o l u t i o n s of c h l o r a l (conc. range 2 t o 1 0 0 % )w i t h i n t h e t e m p e r a t u r e r a n g e 0 t o 7 5 O C ( a t 5-OC i n t e r v a l s ) . These a u t h o r s have a l s o g i v e n a t t e n t i o n t o t h e temperature c o e f f i c i e n t , which, when p l o t t e d a g a i n s t m o l . % o f c h l o r a l , s h o w s a maximum a t 50 m o l . % , c o r r e s p o n d i n g t o t h e f o r m a t i o n o f c h l o r a l h y d r a t e , a n d t w o minima a t a p p r o x . 18 a n d 8 1 m o l . % , r e s p e c t i v e l y . F e r r o n i e t a 1 . 5 6 h a v e a l s o r e p o r t e d v a l u e s for t h e surf a c e t e n s i o n of c h l o r a l h y d r a t e s o l u t i o n s t h a t range from 59.5 f o r 1 molar t o 7 6 . 0 (dyne/cm.) a t i n f i n i t e d i l u t i o n . S u r f a c e t e n s i o n measurem e n t s made on s o l u t i o n s o f c h l o r a l h y d r a t e i n d i e t h y l e t h e r , a c e t o n e , or b e n z e n e 3 ° i n d i c a t e weak compound f o r m a t i o n i n t h e s e s y s t e m s .
JOHN E. FAIRBROTHER
The s u r f a c e t e n s i o n o f c h l o r a l h y d r a t e m e l t s 3 1 4 i n t h e t e m p e r a t u r e r a n g e 5 3 t o 100°C i s expressed ( i n dynes/cm.) by t h e e q u a t i o n u 44.6-0.110(t-53°). The c o n t a c t w e t t i n g a n g l e t 1.5O. o f i t s s o l i d phase i s 18040' Ultrasonic Absomtion
2.44
The v a r i a t i o n o f u l t r a s o n i c v e l o c i t y and a b s o r p t i o n w i t h t e m p e r a t u r e has b e e n r e c o r d e d f o r c h l o r a l h y d r a t e m e l t s ( f o r 7 MHz e m i s s i o n , v e l o c i t i e s r a n g e from 1215 m/sec. a t 5 2 O C t o The u l t r a s o n i c 1 1 2 5 m / s e c . a t 75OC ) l o 1 y 1 O 2 . a b s o r p t i o n c o e f f i c i e n t s (a / V 2 ) f o r c h l o r a l hyd r a t e , when compared w i t h t h o s e o f a m i x t u r e o f c h l o r a l a n d water a t c o r r e s p o n d i n g t e m p e r a t u r e s , show t h a t t h e e f f e c t o f d i s s o c i a t i o n b r o u g h t about by increasing temperature i s t o reduce t h e absorption values. S o l u t i o n s o f c h l o r a l i n non-aqueous s o l v e n t s 2 7 , 3 i show a b s o r p t i o n - c o e f f i c i e n t c u r v e s t h a t p a s s t h r o u g h a maximum i n t h e c a s e s o f a s s o c i a t e d s o l v e n t s s u c h as m e t h a n o l a n d e t h a n o l , corresponding t o t h e formation of a molecular compound 308. 2.45
Viscosity
The v i s c o s i t i e s o f c h l o r a l h y d r a t e melts o b t a i n e d b y u s e o f a n Ostwald Viscometer have been r e p o r t e d 1 0 1 as:-
Temperature 52 to 75
(OC
)
Shear V i s c o s i t y
(q/p)
C.S.
10.10
to 3.40
From t h e t e m p e r a t u r e c o e f f i c i e n t o f t h e s e v i s c o s i t i e s , t h e a c t i v a t i o n e n e r g y of shear v i s c o s i t y o f c h l o r a l h y d r a t e ( m e l t ) has b e e n c a l c u l ated as 1 0 . 6 Kcal/mol. The v i s c o s i t y o f s o l u t i o n s o f c h l o r a l
CHLORAL HYDRATE
i n various hydroxylated organic solvents (aliphatic alcohols, benzyl alcohol, phenols, e t c . ) , has b e e n p l o t t e d a g a i n s t c h l o r a l c o n c e n t r a t i o n s h o w i n maxim wher com ound f o r m a t i o n o c c u r s . 28,33,94,75,7%,77,7b9,b31 2.46
98,?b
C r y oscopy -
''y'cis
The f r e e z i n g - p o i n t s i o n caused l o r a l h y d r a t e i n aqueous and a l c o h o l i c s o l u t i o n s has been d e s c r i b e d .
Van R o s s e m 2 2 6 , s t u d y i n g t h e f r e e z i n g p o i n t c u r v e s of c h l o r a l and water found e v i d e n c e for t h r e e d i f f e r e n t h y d r a t e s : a " s e m i h y d r a t e " (1 m o l e o f water t o 2 m o l e s o f c h l o r a l ) , a monoh y d r a t e (1 m o l e o f e a c h ) , a n d a h e p t a h y d r a t e ( 7 m o l e s o f water t o 1 mole o f c h l o r a l ) . T h e h e p t a h y d r a t e had a s h a r p m e l t i n g p o i n t a t - 1 . 4 % . E u t e c t i c t e m p e r a t u r e s o f 5loC w i t h azobenzene and of 4 0 0 C w i t h b e n z i l have been r e p o r t e d 3 1 3 .
2.47
Refractive Index
The r e f r a c t i v e i n d e x o f a c h l o r a l h y d r a t e melt (at 6 0 . 0 O C ) rises with time94, eventually r e a c h i n g a c o n s t a n t v a l u e a t 1 . 4 8 0 7 ( i . e . m o l a r r e f r a c t i o n MR a t 6 0 O c i s 2 9 . 4 7 ) . The F e f r z t i v e index values obtained with a series of b i n a r y s y s t e m s o f c h l o r a l and v a r i o u s s o l v e n t s indi( i n c l u d i n g water, e t h a n o l , and c a t e t h e f o r m a t i o n o f a n a s s o c i a t i o n compound between c h l o r a l and e a c h s o l v e n t .
2.48
Radiolysis
Aqueous s o l u t i o n s o f c h l o r a l h y d r a t e , when i r r a d i a t e d w i t h X - r a y s , gamma r a y s , or b e t a r a y s , g i v e r i s e t o h y d r o c h l o r i c a c i d as t h e end product of a chain reaction25,I03 t o l l o .
3.
M o l e c u l a r Complexes
3.1
Types o f Known C o m p l e x es
JOHN E . FAIRBROTHER
Chloral forms a range of molecular complexes o r dducts main1 in a 1:1 ratio) with alc oho 1s 22 to 31,$9,92,53 diethy1ether,30,31 benzene, 30,j1 acetone,3°3 31 meprob amate,37 tetracycline,38 oxytetrac cline,38 acetaminophen, 299 and others32 to 36330
E.
Similarly, chloral hydrate has been shown to form c mp exes (main caffeine, betaine, lycinamide , 3 9 9 e 0 3 4 1 58,49 diazepam,50,312 ,5-dimethyl dantoin 52,307 phe a ~ e t i n , ~ 3 , 5phenazon ? tY,56 to 6 1 , glycine,1 7 4 , glucosel?6, urea53,%8 and others. 32,42,4 3,4 8,49,51,53,54,62-67 9 69 173,1753219 3.2 Structure of Complexes 8
A number of the molecular complexes of chloral and chloral hydrate have been shown to be hydrogen-bonded association compounds. The techniques employed in the examination of these complexes are summarized in Table 1. TABLE 1 Techniques used in the characterization of complexes of chloral and chloral hydrate Technique References
26,29,51,55,63,64,66,70,
Cryoscopy
71,72,73 Differential Thermal Analysis Differential Scanning Calorirne t ry Heats of Solution Refractive Index Surface Tension Viscosity Infrared Spectroscopy Raman Spectroscopy X-ray Diffraction Ultrasound Hot-stage Microscopy
62 10,83,84 10,49
74,86 30,43,56 28,33,34,75-81. 10,41,82
57 10,85,312 27,31
86
Chloral hydrate and phenazone form both 108
CHLORAL HYDRATE
(1:l) a n d (2:l) m o l e c u l a r c o m p l e x e s . The s t r u c t u r e o f t h e (1:l) c o m p l e x h a s b e e n s t u d i e d by i n f r a r e d 4 1 a n d Raman57 s p e c t r o s c o p y , i n a d d i t i o n t o a s u r f a c e - t e n s i o n 5 6 s t u d y t h a t examined b o t h complexes. The i . r . a n d Raman d a t a s u g g e s t a s t r o n g l y hydrogen-bonded complex, w i t h t h e associa t i o n a t t h e c a r b o n y l oxygen o f t n e p h e n a z o n e a n d not a t t h e n i t r o g e n . Infrared studies of t h e c o m p l e x i n c a r b o n t e t r a c h l o r i d e s o l u t i o n havi? been used t o c a l c u l a t e a s t a b i l i t y c o n s t a n t f o r t h e c o m p l e x (l:l), a n d c r y o s c o p i c m e a s u r e m e n t s on d i l u t e a q u e o u s s o l u t i o n s show t h e m o l e c u l a r compound t o b e c o m p l e t e l y d i s s o c i a t e d i n w a t e r 4 1 . T h e c r y s t a l 2nd m o l e c u l a r s t r u c t u r e o f (1:1) m o l e c u l a r c o m p l e x o f c h l o r a l h y d r a t e and bromodiazepam has b e e n d e t e r m i n e d b y x - r a y
the
diffraction studies312.
4.
S y n t h e s i s and P u r i f i c a t i o n
C h l o r a l l i y d r a t e wa's f i r s t o b t a i n e d b y L i e b i g ( 1 8 3 2 ) from t h e r e a c t i o n o f w a t e r w i t h c h l o r a l , t h e l a t t e r o b t a i n e d v i a t h e c h l o r i n a t i o n of
ethanol. I n d u s t r i a l l y , c h l o r a l i s prepared by passing chlorine i n t o cooled ethanol ( e i t h e r abs o l u t e o r 9 5 p e r c e n t ) t o form t h e h e m i a c e t a l o f t r i c h l o r o a c e t a l d e h y d e , from which c h l o r a l i s liberated by treatment w i t h s u l f u r i c a c i d . It has been found,
ev.r,
t h a t t h e herni-
a c e t a 1 may b e h y d r o 1y ze iJ.' g B ~ 2 k g b y t h e a d d i t i o n o f water, g i v i n g c h l o r a l h y d r a t e and a l c o h o l .
The o v e r - a l l r e a c t i o n may b e r e p r e s e n t e d b y the equation:E t O I l + 4Cl2 + li20 + C l , C C H ( O H ) 2 + 5 H C l 13ther p r o c e s s m o d i f i c a t i o n s i n c f u d e t h e r e p l a c e ment o f e t h a n o l w i t h e t h a n o l - a c e t i c a c i d m i x tures i n t h e c h l o r i n a t i o n step2T0, with recycling of t h e l e s s v o l a t i l e byproducts, such as c h l o r a l a c e t a t e , c h l o r a l a l c o h o l . a t e , b u t y l c h l o r a l , and 109
JOHN E. F A I R B R O T H E R
trichloroacetic acid. Crude c h l o r a l i s s e p a r a t e d by f r a c t i o n a t i o n from v o l a t i l e byproducts s u c h as e t h y l c h l o r i d e , e t h y l e t h e r , e t h y l e n e d i c h l o r i d e , and a l c o h o l , and t h e c h l o r a l r ' c u t r r i s t a k e n between 9 3 and 9 8 O C . T h i s material1g0 c o n t a i n s 2 t o 3% wateri n s o l u b l e material c o n t a i n i n g e t h y l d i c h l o r o a c e t a t e , e t h y l t r i c h l o r o a c e t a t e , and t r i c h l o r o acetal. The t e c h n i c a l c h l o r a l s e p a r a t e d from the o i l contains acetic acid (0.2 t o 0.8%), dic h l o r o a c e t a l d e h y d e ( 2 t o 5%), e t h y l d i c h l o r o a c e t a t e (about 0 . 3 % ) , e t h y l t r i c h l o r o a c e t a t e ( a b o u t 0 . 6 % ), a n d t r a c e s o f c h l o r a l a l c o h o l a t e 1 g 0 . The c h l o r a l h y d r a t e f o r m e d b y t r e a t i n g t h e c h l o r a l w i t h a n a p p r o p r i a t e q u a n t i t y o f w a t e r may c o n t a i n t r a c e s o f t h e above i m p u r i t i e s and a l s o t r i c h l o r o a c e t i c a c i d ( o x i d a t i o n p r o d u c t ) or t r i c h l o r o e t h a n o l ( r e d u c t i o n p r o d u c t ) . The c r u d e c h l o r a l h y d r a t e may t h e n b e p u r i f i e d f u r t h e r by r e c r y s t a l l i z a t i o n from a n o r g a n i c s o l v e n t s u c h as b e n z e n e . An a l t e r n a t i v e i n d u s t r i a l r o u t e t o c h l o r a l i s by t chlorination of acetaldehyde o r parald e h ~ d e 271 ? ~ ~ ~ C H CHO
3
+ 3C12-Cl
3
C C H O + 3HC1
Alternative laboratory preparations include t h e r e a c t i o n o f etli 1 f o r m a t e w i t h s u l f u r y l and t h e r e a c t i o n of c h l o r o chloride at 17OoC a c e t y l e n e w i t h sodium h y p o c h l o r i t e s o l u t i o n and s a t u r a t e d boric a c i d solution273. The p r e a r a t i m o f h i g h - p u r i t y c h l o r a l h a s b e e n a c h i e v e d 2 2 1 by h e a t i n g m e t a c h l o r a l a t 180-2OO0C.
2y2
5.
Degradation
5.1
Degradation o f S o l i d Chloral Hydrate
5.11 V o l a t i l i z a t i o n Chloral hydrate crystals,
l e f t open t o
C H L O R A L HYDRATE
t h e a i r , v o l a t i l i z e s l o w l y as c h l o r a l and water. C o n d e n s a t i o n of t h e mixed d i s s o c i a t e d v a p o r s gives back c h l o r a l hydrate?. Chloral hydrate i n sealed containers w i l l only volatilize u n t i l e q u i l i b r i u m v a p o r p r e s s u r e has b e e n a t t a i n e d 8 9 . V o l a t i l i z a t i o n may b e d e t e r m i n e d b y m e a s u r e m e n t o f w e i g h t l o s s 1 7 3 , b y G.L.C a s ~ a y * 5 ~ or by G.L.C. a s s a y o f t h e u l l a g e gases84 o f t h e container. 5.12
Chemical Degradation
Degradation of c h l o r a l hydrate occurs i n t h e p r e s e n c e o f a n e x c e s s o f free oxygen t o form phosgene, C 0 2 , and H C I , b u t only a f t e r a c o n s i d e r a b l e lag-phase (52 days)227, u n l i k e anh y d r o u s c h l o r a l , w h i c h d e c o m p o s e s much m o r e rapidly22?. Exposure of c h l o r a l h y d r a t e t o s u n l i g h t i n t h e a b s e n c e o f oxygen g e n e r a t e s no s i g n i f i c a n t l e v e l s of gaseous degradation products, even a f t e r 160 d a y ~ ~ ~ 7 . T r a c e s o f w a t e r may c a u s e t h e d e g r a d a t i o n o f c h l o r a l h y d r a t e to d i c h l o r o a c e t a l d e h y d e , t r i c h l o r o a c e t i c a c i d and h y d r o c h l o r i c a c i d ; t r a c e of a l k a l i l e a d t o t h e f o r m a t i o n o f c h l o r o f o r m a n d f o r m i c a c i d 2 1 7 91. 5.2
Degradation of Chloral Hydrate i n Solution 5.21
t A c t i o n o f L i g h-
It h a s b e e n proposed217,21? that; n e u t r a l a q u e o u s s o l u t i o n s of c h l o r a l h y d r a t e decompose by an oxidation-reduction process. 2 ClTCCII’3 ~
t
E20+Ci2CfICHO
t
IH(‘1 + C l j C C O O H
E x p o s u r e o f s o l u t i o n s t o l i g h t g r e a t l y a c c e l e r ; tes t h i s ~ I ’ O C E S S , as may Le d e m o n s t r d a t e d b y m e a s u r e -
JOHN E . FAIRBROTHER
ment of t h e f o r m a t i o n o f f r e e h y d r o c h l o r i c a c i d . 5.22
A c t i o n o f Heat
On w a r m i n g , n e u t r e l a n d s l i g h t l y a c i d i c a q u e o u s s o l u t i o n s of chloral h y d r s t e a p p e a r t o degrEde t o t r i c h l o r o a c e t i c a c i d d i c h l o r o a c e t a l dehyde, and h y d r o c h l o r i c a c i d 2 1 f . 5.23
U l t r a s o u n d ( S o n o c l e a v a g-e )
Exposure of aqueous s o l u t i o n s o f c h l o r a l h y d r a t e t o h i g h - e n e r g y u l t r > a s o u n d ( 1 M H z ; 1.8kV) has b e e n showri220 t o c a u s e a d e g r a d a t i c n o f t h e c h l o r a l h y d r z t e t h a t follows z e r o - o r d e r k i n e t i c s . The m a i n d e g r a d a t i o n p r o d u c t s a r e h y d r o c h l o r i c a c i d and d i c h l o r o a c e t a l d e h y d e .
5.24
A u t o x i d a t -__-i o n and P o l . y m e r i z a tion
A n h y d r o u s c h l o r a l h a s b e e n shown t o u n d e r g o a u t o x i d a t i o n i n a i r 2 2 7 v i a b o t k of t h e f o l l o w i n g r e a c t i o n s and p o s s i b l y o t h e r s . C13CCHO
t 0
->Cl3CCOOH
C l 3 C C H O + 02+COC12
t
C 0 2 t HCI
The a c t i o n of l i g h t a p p e a r s t o b e n e c e s s a r y for at least t h e iriitial formation of t h e peroxide c a t a l y s t . A n t i - o x i d a n t s , s u c h as h y d r o q u i n o n e ,
r e s o r c i n o l , a n d a- and 6 - n a p h t h o l s , d e c r e a s e t h e o x i d a t i o n r a t e , whereas complete p r o t e c t i o n i s g i v e n 2y a n i l i n e , d i p h e n y l a m i n e , and r e l a t e d compounds r 8 . I n a d d i t i o n t o t h e g a s e o u s p r o d u c t s of a u t o x i d a t i o n , a s o l i d p o l y m e r t h o u g h t t o b e m e t a c h l o r z l i s formed. C h l o r a l h y d r a t e does n o t a p p e a r t o u n d e r g o a u t o x i d a t i o n un s s it. f i r s t d i s s o c i a t e s t o c h l o r a l a n d water 2 3 9
.
S t r o n g sulfuric a c i d c a u s e s t h e polymeri y a t i o n of c h l o r a l t o f o r m a- a n d 8- p a r a c h l o r a l s * 3 l , wkiich h a v e b e e n shown t o b e s t e r e o i s o m e r : o f t h e c y c l i c t r i n i e r of ~ h l o r a . 1 ~ 3 ~ , ~ “lore 3 3 . dilute su 1furi c a c id p r o d u c e s t ki e amo r1i h o 11 s m e t a c h 1o r a 1
CHLORAL H Y O R A T E
231, w h ' c h may b e a n o n c y c l i c p o l y m e r o f c h l o r a l hydrate& ,
.
The a n i o n i c . p o l y m e r i z a t i o n o f c h l o r a l h a s b e e n s t u d i e d a t -78OC, w i t h B u L i a n d sodl.um rtaphthalene234 tcl 236 used as i n i t i a t o r s .
5.25 C h l o r a l h y d r a t e decomposes i n d i l u t e a q u e o u s s o l u t i o n s o f sodiuni h y d r o x i d e 9 8 . T h i s f j r s t - o r d e r r e a c t i o n i s c a t a l y s e d by t h e h y d r o x y l i o n s , by t h e c h l o r h l a t e i o n a n d b y w a t e r . It p r o c e e d s v i a a n i n t e r m e d i a t e b i v a l ent, c h l o r a l a t e i o n which decomposes f u r t k e r t o g i v e c h l o r o f o r m and t h e formate ion. F u r t h e r s t u d i e s by P f e i l e t a 1 . 2 3 7 i r i d i c a t e tflat i n t h e p r e s e n c e o f e x c e s s T a E t h e r e a c t i o n i s f i r s t o r d e r arid t h e r a t e i r r c r e a s e s a l m c , s t l i n e a r l y w i t h b a s e c o n c e n t r a t i o n . However, fcir e q u i n o l a r c o n c e n t r * a t i o n s t h e r e a c t i o n becomes secorid o r d e r 2nd w i t k l e x c e s s c h l o r a l h y d r ; t e t h e k l y d r o l y s i s o f t h e C l j C - g r o u p becomes t h e p r e dorriin;nt r e a c t i o n . The a d d j t i o n o f s o l v e n t s o f low d i e l e c t r i c c o n s t a n t (such as dioxan) i n c r e a s e s t h e r a t e of a c t i v i t y towards t h e degradation of c h l o r z l h y d r c t e t o v a r y f o r a r a n g e o f h y d r c l x i d e s 6s follows: Lj 6 Na
< Ba 4 T 1
T u c h e l e t a1 . 2 7 8 , 2 3 9 , 2 4 f i have a l s o e x amined t h e k i n e t i c s cf t k e d e g r a d a t i o n o f c h l o r a l h y Z r a t e i n s o l u t i o n s c o n t a j n i r . g sodium h y d r c j x i d e , b o r a x , d i s o d i u m h y d r o g e n phospl-,ate and s o d i u m p h e n o b a r b i t a l . I n a d d i t i o n , these a u t h o r s exarlined t h e s t , a b i l i z i n g e f f e c t o f c e r t a i n c o l l o j d s (gum a r c b i c , a g a r - a g a r , a n d g e l a t i n ) or] m i x e d soluticins of c h l o r a l h y d r a t e and s o d i u n phenobarbital.
JOHN
5.26
E. FAIRBROTHER
R a d i o l y s~ is -
-
Andrews a n d S h o r e l O 7 r e p o r t e d t h a t a q u e o u s s o l u t i o n s o f c h l o r a l h y d r * a t e were decomp o s e d on i r r a d i a t i o n w i t h x - r a y s ( 5 0 - 2 0 0 k v . ) t o f o r m h y d r o c h l o r i c a c i d a n d a s m a l l e r amourlt o f a w e a k 1 i o n i s e d a c i d . Many o t h e r a u t h o r ~ ~ 5 , ~t O o 3 106,188 t o 1 1 0 , 2 4 1 , 2 4 2 h a v e e x a m i n e d t h e i r r a d i a t i o n of c h l o r a l h y d r a t e s o l u t i o n s w i t h x - r a y s , gamma-rays or b e t a - r a y s . I n a l l c a s e s i t i s SUEg e s t e d t h a t t h e c h l o r a l h y d r a t e decomposes t o hydrochloric acid v i a a chain reaction. 5.27
anisms A c t i o n o f M i c r o o r g--
The d e g r a d a t j o hloral hydrate i n s o i 1s h a s b e e n e x am i n e d 2Q3y’4‘ a n d t h e r e s u l t s suggest t h a t m i c r o o r g a n i s m s p a r t i c j p a t e i n t h e d e g r a d a t i o n i n c o n j u n c t i o n w i t h chemlcal and photochemical pi-ocesses . 5.28
Incompat ib -
i l i ties
___I-
C h l o r a l h y d r z t e h a s b e e n shown t o b e c h e m i c a l 1 y i n c o m p a t i b l e w i t h many c o n p o u n d s . It i s p r o b a b l e t h a t it i s incornpati-ble w i t h a l l s u b s t a n c e s f o r m i r i g c o m p l e x e s w i t h j.t or w i t h c h l o r a l ( s e e S e c t i o n 3 . 1 , T a b l e s 1 a n d 2 ) , w i t h m o s t bases ( s e e S e c t i o n 5 . 2 5 ) a n d w i t h many compounds bearing hydroxyl groups, The f o l l o w i n g t a b 1 e l i s t s s u b s t z n c e s known t o b e i n c o m p a t i b l e w i t h c h l o r a l h y d r a t e ( o t h e r t h a n known c o m p l e x f o r m e r s ) .
114
CHLORAL HYDRATE
S u b s t a n c e s Show
r
I
v strong Dispersion R e f r a c t i v e 1 n d e x e s : a ( a ) = 1.559 B (E) = 1.579 Y = 1.649 Density: .337 Molar R e f r a c t i o n : E x p e r i m e n t a l = 99.64 Calculated = 98.59
Two c r y s t a l forms of dexamethasone have been o b s e r v e d t o d a t e . The X-ray powder d i f f r a c t i o n d a t a f o r t h e two forms A and B a r e g i v e n i n T a b l e I . 3 Because of v a r i a t i o n s enc o u n t e r e d i n peak i n t e n s i t y from sample t o s a m p l e , no l i s t i n g of t h e r e l a t i v e i n t e n s i t y of t h e bands i s g i v e n . The two c r y s t a l forms have e s s e n t i a l l y t h e same s o l u b i l i t y i n water and e s s e n t i a l l y t h e same d e c o m p o s i t i o n t e m p e r a t u r e . Form B i s t h e more u s u a l l y o b s e r v e d form. No s o l v a t e s o r polymorphic m o d i f i c a t i o n s of dexarnethasone were r e p o r t e d by Mesley4 3 f o r dexamethasone c r y s t a l l i z e d from c h l o r o f o r m , a c e t o n e and e t h a n o l u s i n g X-ray d i f f r a c t i o n p a t t e r n s and s o l i d s t a t e I . R . s p e c t r a t o e v a l u a t e samples.
2 . 2 I n f r a r e d Spectrum ( I . R . S . ) Mesley r e p o r t s t h e f o l l o w i n g band a s s i g n m e n t s f o r t h e s o l i d s t a t e I.R.S . of dexamethasone ( m i n e r a l o i l m u l l ) .
I66
DEXAMETHASONE
TABLE I
X-Ray Powder Diffraction Pattern of Dexamethasone Sample - Merck Standard 88415-76 Cu-K, Radiation Form Ba
20"
db -
5.95 6.92 7.45 8.50 8.80 10.55 12.50 13.60 14.20 15.10 15.60 16.80 17.70 18.10 18.50 19.70 20.40 21.60 22.20 22.80 23.50 25.00 26.10 26.75 27.95 28.50 29.00 30.10 30.15 31.70 33.70 37.40 44.40
14.80 12.75 11.83 10.38 10.03 8.36 7.07 6.50 6.23 5.90 5.67 5.27 5.00 4.89 4.79 4.50 4.35 4.11 4.00 3.89 3.78 3.56 3.41 3.33 3.19 3.13 3.07 2.96 2.96 2.82 2.65 2.40 2.04
_c
5.70 15.48 7.95 11.10 9.90 8.92 12.45 7.10 13.50 6.55 14.45 6.12 14.95 5.91 16.10 5.49 17.65 5.02 19.25 4.60 20.00 4.43 20.60 4.30 20.90 4.24 21.00 4.22 25.00 3.56 22.30 3.98 23.00 3.86 23.65 3.76 24.00 3.70 24.70 3.60 25.20 3.53 26.30 3.38 26.70 3.33 27.20 3.27 27.30 3.26 27.70 3.21 28.25 3.15 29.10 3.06 29.65 3.01 31.10 2.87 32.25 2.77 31.70 2.82 32.10 2.78 aMerck Standard 118415-76 bCu-K, Kadiation
EDWARD M. COHEN
Wavelength ( cm.- )
Vibrational Modes
1043 1135, 1117 1090, 1056 1408, 1297, 1242 952, 930, 893, 852 830, 703
1lB-OH 17a-OH 21-OH lY4-diene-3-one
Clark lists 1655 cm.-l, 1616 cm.”, and 892 ern.-' as distinctive bands for the KBr disc I.R.S. of dexamethasone.6 Figure 1 shows the I.R.S. of Merck Standard #8415-76. Principal bands and their assignments are tabulated below. The spectrum is in substantial agreement with published I.R.S. of dexamethasone.5,6,8 Wavenumber of Assignment (cm.-’)
Vibrational Mode
3400-3675 3020, 3050 2850-3000 (severa1 bands ) 1700 1660 1620, 1600 1130-1040 (several bands) 890
OH stretch Olefinic CH stretches Aliphatic CH stretches C20 carbonyl C 3 carbonyl stretch A-ring, C=C stretch Various C-OH stretches A 1 y4-diene-3-ketone
2.3 Ultraviolet Absorbance Dexamethasone exhibits a single major absorbance band at about 240 nm. in solution attributable to the A-1,43 keto A ring chromophore. The following data have been reported in the literature: (E)
Solvent
X Maximum
cm.
Methanol Methano1 Methanol
240 nm. 238 nm. 240 nm.
355(13,920) 392(15 ,400) 380-410
168
Reference (6) (8) (9)
2.5
3
4
5
WAVELENGTH MICRONS 6 7 8 9 10
12 14
18 22 35 5 0
I00
100
80
80
60
60
k 40
40
8 w
u
z
bU -
r
U J
z U
0 4000 3500 3000
F i g u r e 1.
20
20 1
2500
2000
1700 1400 FREQUENCY (CM-' )
1100
1
1
800
500
0
200
I n f r a r e d S p e c t r u m of D e x a m e t h a s o n e ; S p l i t M u l l T e c h n i q u e F l u o r o l u b e m u l l a b o v e 1 3 3 5 crn.-l M i n e r a l o i l m u l l b e l o w 1 3 3 5 c m - I (Merck S t d . # 8 4 1 5 - 7 6 ) .
X
EDWARD M. COHEN
F i g u r e 2 shows a n u l t r a v i o l e t s c a n of dexamethasone (Merck S t d . 118415-76) i n m e t h a n o l a t a c o n c e n t r a t i o n of 0.00127%. A s i n g l e a b s o r b a n c e maximum a t 240 nm. was o b t a i n e d w i t h a n
cm.
of 393 (15,400).1°
In c o n c e n t r a t e d s u l f u r i c a c i d , t h e u l t r a v i o l e t a b s o r b a n c e s p e c t r u m o f dexamethasone undergoes a b a t h o c h r o m i c s h i f t c h a r a c t e r i s t i c of a number of s t e r o i d s . S p e c t r a l d a t a rep o r t e d f o r dexamethasone i n c l u d e : 1% Max.
cm.
262 nmSa 305 nm.a 263 nm. b
-444 - 308 422-455
Reference
11 11
6
aTwo h o u r s i n c o n c e n t r a t e d H 2 S 0 4 bNo c o n d i t i o n s s p e c i f i e d The s p e c t r a l change n o t e d f o r dexamethasone i n c o n c e n t r a t e d s u l f u r i c a c i d i s p r o b a b l y due t o t h e i n i t i a l p r o t o n a t i o n o f t h e A-1,4-3 k e t o f o l l o w e d by a coupled c h e m i c a l r e a c t i o n s i n c e t h e s p e c t r a l changes a r e a p p a r e n t l y i r r e v e r s i b l e . l 2
2.4 O D t i c a l R o t a t i o n The f o l l o w i n g s p e c i f i c r o t a t i o n s have been r e p o r t e d : 25"
IUID = +75 t o 80" (C = 1 i n d i o x a n e ) ' [u]22-240C = 86" (C = 1 i n d i o x a n e ) 8 D [ a I h 5 " = +77.5" ( C = 1 i n d i o x a n e ) l = +72 t o 80" ( C = 1 i n d i ~ x a n e ) ~ 2.5 S o l u b i l i t y The f o l l o w i n g s o l u b i l i t y d a t a a r e g i v e n i n t h e literature:
rn 0
200
250
300
350
WAVELENGTH, n m
Figure 2.
Ultraviolet Absorption Spectrum of Dexamethasone in Methanol at a Concentration of 0.00127% - 2.max. 240 nm. and E1% = 393 lcm. (Merck Std. #8415-76).
EDWARD M. COHEN
So l v e n t
Tempe ra t u r e
D i s t i l l e d Water D i s t i l l e d Water D i s t i l l e d Water Isopropyl Myris t a t e Light Mineral Oil
Ethanol Chloroform Acetone Ether E t h y l Acetate Pyridine
Solubility
Reference
37°C. 25°C. 25 " C.
1 1 . 6 mg/100 m l 8 . 4 mg/100 m l 1 0 . 0 mg/100 m l
14 15 1
37°C.
2 3 . 3 mg/100 m l
14
37°C.
0 . 0 1 mgI100 m l 1 i n 42 1 i n 165 soluble very s l i g h t l y soluble 4 . 1 mg/g
14 9 9 9
--
--
--25°C.
--
13 16
- 10%
7
2 . 6 N u c l e a r M a g n e t i c Resonance Spectrum (NMRS) The 60 MHz NMRS of a 10% s o l u t i o n of dexamethasone i n d e u t e r a t e d p y r i d i n e ( d 5 ) i s shown i n F i g u r e 3. T a b u l a t e d below are t h e p r o t o n a s s i g n m e n t s f o r t h e o b s e r v e d c h e m i c a l s h i f t s and c o u p l i n g c o n s t a n t s . 7 R e l a t i v e // of P r o t o n s
Chemical S h i f t ppm'
7. 55/doublet 6.6?/crude doublet 6.5 4 / q u a r t e t 6.43/~inglet 6.35/unresolved multiplet 5.g4/broad s i n g l e t 4.9?/AB q u a r t e t 4.73/crude doublet 1.74/singlet 1.4 / s i n g l e t 1.1 / d o u b l e t 0.88-3.80 complex overlapped s i g n a l s
-1.1
Assignments C W E f
11-OH
3.9
1.1 3.1
19.8
172
C ( 2 1)-Hz
(19) -H3 '61 8i:" 3 1 -c J A l l remaining protons
500 100 25
-I
I
cn P
I
0
z m
I
F i g u r e 3. NMR S p e c t r u m o f D e x a m e t h a s o n e i n D e u t e r a t e d P y r i d i n e ; O p e r a t i n g 51.5 C o n d i t i o n s S i g n a l : 6 0 MHz S a m p l e : Merck S t d . # 8 4 1 5 - 7 6 , m g . / . 5 c c . of CgDgN, Sweep Time: 250 s e c . S p e c t r u m A m p l i t u d e : 1 . 2 5 x 10. I n t e r n a l S t a n d a r d : T e t r a m e t h y l s i l o n e
EDWARD M. COHEN
u s e d as i n t e r n a l r e f e r e n c e 2Coupling c o n s t a n t 3Based on 29 p r o t o n s f o r sum of t o t a l s p e c t r a l i n t e g r a l 4Assignment c o n f i r m e d v i a D 2 0 exchange 'TMS
2 . 7 Thermal B e h a v i o r M e l t i n g P o i n t - The m e l t i n g p o i n t of dexamethasone i s r e p o r t e d t o depend i n p a r t on t h e r a t e o f h e a t i n g and t h e d e g r e e of powder f i n e n e s s . " Some of t h e r e p o r t e d values include: Melting Point -250" -255" 263" - s a m p l e r e c r y s t a l l i z e d from e t h e r 256-258" 262-264" - c r y s t a l s from e t h e r 2 6 8-2 72 "
Reference 13 9 17 8 1
1
D i f f e r e n t i a l S c a n n i n g C a l o r i m e t r y - The thermogram o b t a i n e d on a P e r k i n E l m e r DSC 1-B, 2 0 " l m i n u t e f o r dexamethasone (Merck S t d . #8415-76) e x h i b i t s t h e f o l l o w i n g thermal e v e n t s (Figure 4 ) : 1. 2.
S m a l l exotherm a t -254-258" Complex m e l t i n g endotherm - 258" - 267"
-
o n s e t temp.
- p e a k temp.
2 . 8 Mass S p e c t r a (MS) The low r e s o l u t i o n MS of dexamethasone h a s been described i n the l i t e r a t u r e . l e l~ 9 I m p o r t a n t f e a t u r e s of t h e spectrum i n c l u d e : 1. 2.
3.
Absence of a m o l e c u l a r i o n peak. Major p e a k a t m / e 343 (M.W. - 49) a t t r i b u t e d t o l o s s of water from t h e D-ring f o l l o w e d by c l e a v a g e of t h e C 1 8 - C 2 1 bond. The most i n t e n s e p e a k of t h e MS o c c u r s a t m / e 122 accompanied by a m a j o r p e a k a t m / e 121 a r i s i n g from c l e a v a g e of cg-c7 and C g C l 0 bonds and t r a n s f e r o f two (m/e = 1 2 2 )
174
40 5
-
U
P +-
4 'A
w 1 X W
0 l
~
280
1
l
250
l
I
1
I
I
I
200
1
I
1
1
1
150
1
1
1
1
,
100
1 in "C
Figure 4.
Thermogram of Dexamethasone (Merck S t d . #8415-76); Perkin Elmer - D . S . C . - 1 B ; 20°/min.; sealed p a n with N 2 sweep.
D.S.C.
EDWARD M, COHEN
o r one hydrogen ( m / e = 1 2 1 ) t o t h e charged fragment. The a u t h o r s 1 8 * l9 c l a i m t h a t b e t a m e t h a s o n e , t h e 166-methyl iosmer of dexamethasone, can b e u n e q u i v o c a l l y d i s t i n g u i s h e d from dexamethasone by t h e v i r t u a l a b s e n c e of t h e m / e p e a k a t 343. Formation of t h e m / e 343 d i a g n o s t i c f r a g m e n t was a t t r i b u t e d t o a f a c i l e t r a n s - e l i m i n a t i o n of water from dexamethasone It is f o l l o w e d by c l e a v a g e o f t h e a l l y l i c C z o - C z l bond. q u i t e c o n c e i v a b l e t h a t i n i t i a l e l i m i n a t i o n of water o c c u r r e d under t h e r m a l s t r e s s r a t h e r t h a n u n d e r e l e c t r o n i m p a c t alone i n t h e reported d a t a . l 8 > l 9
Attempts t o c o r r o b o r a t e t h e r e p o r t e d l i t e r a t u r e f i n d i n g s w i t h r e s p e c t t o t h e p r e s e n c e of m / e 343 as a m a j o r peak f o r dexamethasone were n o t s u c c e s s f u l i n Merck l a b o r a t o r i e s . 2 0 F i g u r e 5 shows t h e low r e s o l u t i o n MS of dexamethas o n e o b t a i n e d on an LKB-5000 mass s p e c t r o m e t e r a t 70 e V i o n i z a t i o n e n e r g y , S i g n i f i c a n t d i f f e r e n c e s between t h e s p e c t r a of dexamethasone and b e t a m e t h a s o n e w e r e found i n t h e r e l a t i v e p e a k h e i g h t a t m / e 315 and 3 4 3 , a s l i s t e d below ( i n p e r c e n t o f t h e b a s e p e a k s a t m / e 1 2 2 ) .
176
l-
a
-I W c
tx
.I
I
m /e
Figure 5.
M a s s S p e c t r u m o f D e x a m e t h a s o n e (Merck S t d . # 8 4 1 5 - 7 6 ) LKB-5000 - 7 0 e V i o n i z a t i o n e n e r g y .
E D W A R D M. C O H E N
Dexamethasone
Betamethasone
- 1% - 1% - 1% - 1%
-1% - 1% - 1%
rnfe rnfe m/e m/e mfe m/e rnfe
392 374 372 362 354 343 342 m/e 333 m / e 315 m / e 312
- 1% - 1%
-1% 15% 13%
5% 19% 6%
3% 3% 10%
12% 9%
M+ M-H20
M-HF M-CH20
M-(H20 + HF) see below 362 - HF M- (CO-CH 20H) see below 372-(CO-CH20H
+
H)
A r e a s o n a b l e i n t e r p r e t a t i o n of t h e s e two f r a g m e n t s i s b a s e d on t h e w e l l known a c i d c a t a l y z e d water e l i m i n a t i o n from 17a-hydroxy s t e r o i d s w i t h c o n c o m i t a n t m i g r a t i o n of t h e 18methyl g r o u p from C - 1 3 t o C-17. I n t h e c a s e of dexamethas o n e t h e c i s - c o n f i g u r a t i o n of t h e C-17 k e t o l and C-16-methyl groups i n t h e r e a r r a n g e d i o n rnfe 374 f a v o r s t h e d i r e c t breakdown t o rnfe 315 w h i l e t h e t r a n s - c o n f i g u r a t i o n ( b e t a methasone) a l l o w s € o r a h i g h e r p e r c e n t a g e of t h e i n t e r m e d i a t e i o n m / e 343.
-0
CH20H
d-
GH3
M@
3 3
0
I co H
-
1 L
m / e 374
178
DEXAMETHASONE
3 . Synthesis Dexamethasone can be synthesized starting from 16amethyl hydrocortisone acetate, an available intermediate of bile acid origin. 2 1 (Figure 6). While the original synthetic scheme required a selenium oxide l-dehydrogenation2*, subsequent work established that 1-dehydrogenation could be accomplished for any number of appropriate intermediates by using microorganisms of the class Schizomycetes. An entirely different synthetic scheme for dexamethasone starting from diosgenin has also been reported.2" The synthesis of both tritium labeled and carbon-14 labeled dexamethasone has been given in the literature. The following labeled material has been prepared:
1. 'H at positions 1, 2 and 4 . 2. General tritium labeling. 3. 14C in the 16-i-methyl carbon. 4 . 'H in the l6B-hydrogen. This type of labeled material provides a very sensitive handle for use as a tracer in subsequent chemical and biological studies.
4 . Stabilitv Chemical properties of the reactive mioeties of dexamethasone - A consideration of the stability information reported for dexamethasone is best viewed in connection with the molecular changes reported for dexamethasone as well as structurally related adrenocorticosteroids. A-Ring - The A' 9 43-keto grouping of prednisone acetate can undergo photocatalyzed transformations leading to a variety of compounds whose composition depend on the conditions of the experiments. 26 Two such characteristic products are shown below. Further irradiation of Compound VIII can lead to a photoinduced diene-phenol rearrangement. I t is reasonable to assume that dexamethasone can undergo similar photochemistry with the course of reaction duely influenced by the presence of the 92-fluoro group.
179
EDWARD M . COHEN
Figure 6.
CH2 O C - CH3 I ;
c=o
KC2H302
1-21-ACETATE
1
NaOCH3/GH30H
Se02
0
180
DE XAME THASONE
Vlll
VII
(A max. -233 nm. in ETOH)
(Lumiprednisone, X max. -218 nm. and 265 nm.)
Sodium bisulfite adds reversibly to the A - 1 position of dexamethasone-21-phosphate sodium forming a 1-sulfonate as shown below. 27
so’,
HSOS
1-21 PHOSPHATE S O D I U M
IX
From the data obtained, it is assumed that the active nucleophile is the dianionic sulfite ion. This reaction is typical of conjugate sulfite addition to a,@-unsaturated ketones. It should be inferred that other active nucleophilic agents may behave in a similar manner. B-Ring - The 9a-fluoro aliphatic substituent would be expected to be quite stable to hydrolytic displacement. Indeed, there are no reported instances of liberation of fluoride from the 9cu-f luoro adrecocorticosteroids in-vivo.
181
*
E D W A R D M. COHEN
C-Ring - The 11-6-hydroxyl g r o u p of s e v e r a l c r y s t a l l i n e a d r e n o c o r t i c o s t e r o i d esters undergoes a i r o x i d a t i o n , catal y z e d by b o t h t e m p e r a t u r e and l i g h t , t o form t h e c o r r e s p o n d i n g 11-one compounds. 2 9 S t r u c t u r a l r e q u i r e m e n t s f a v o r i n g t h i s t r a n s f o r m a t i o n are t h e f o r m a t i o n o f a nons t o i c h i o m e t r i c s o l v a t e which u n d e r g o e s f a c i l e d e s o l v a t i o n w i t h o u t change i n t h e X-ray d i s c e r n i b l e c r y s t a l l i n e l a t t i c e s t r u c t u r e . I t was a l s o shown t h a t 11-p-hydroxy s t e r o i d s c a n b e a i r o x i d i z e d i n s o l u t i o n u n d e r somewhat r i g o r o u s c o n d i t i o n s . I n g e n e r a l , t h e r e a c t i o n r e q u i r e s m o l e c u l a r oxygen a n d p r o d u c e s water. I t i s a c c e l e r a t e d by h e a t , g r e a t l y a c c e l e r a t e d by f r e e - r a d i c a l i n i t i a t o r s o r by U.V. l i g h t , a n d i s quenched by f r e e - r a d i c a l i n h i b i t o r s . T h e s e a u t h o r s d i d n o t r e p o r t on any f r e e C - 2 1 a l c o h o l s . D-Ring - The C-17 d i h y d r o x y a c e t a t e s i d e c h a i n , a c h a r a c t e r i s t i c s t r u c t u r a l f e a t u r e of a l l a d r e n o c o r t i c o s t e r o i d s , i s q u i t e s u s c e p t i b l e t o b o t h a e r o b i c and a n a e r o b i c t r a n s f o r m a t i o n s . The a n a e r o b i c c h a n g e s of t h e s i d e c h a i n a r e c o n s i d e r e d by Wendler as f o l l o w s :
c.0
CHOH II C-OH
X
XI
Io2
COOH
CH20H I
COOH
OH XVI
HC.0 I CHOH
0
Xlll
I CHOH
xv
XIV
182
DE XAMETHASONE
Conversion of X to the C-17 ketone (XIII) is considered as a reverse aldol reaction. Conversion of the keto-aldehyde (XIV) to the hydroxy acid (XV) is considered a benzillic acid rearrangement. The predominant reaction, under base catalyzed aerobic conditions, appears to be oxidative cleavage of the side chain to the corresponding etianic acid (XVI). Formation of C-17 ketone is only a minor reaction product.31 An alternative mode of oxidative change at the C-21 position is the formation of a glyoxal (XVII) side chain which was found to be metal catalyzed.32 This glyoxal might be expected to undergo coupled chemical reactions consistent with the reactivity of that functionality. HC=O I
c=o
OH XVI I
The D-homo rearrangement reported for 17n-hydroxy-20-keto steroids is adequately described by Wendler.3 3 Possible products of this rearrangement are shown below.
-
c=o
MAJOR
xx
H O ,CH3
MAJOR XVlll
XIX
While not specifically described in the literature, the D-homo rearrangement may be a possible occurrence for dexamethasone under certain reaction conditions by analogy with other steroids such as triamcinolone.34 183
EDWARD M. COHEN
Other possible reactions involving the C-17 side chain include acylation of the C - 2 1 hydroxyl group with available acylating agents. Prednisolone was reported to transesterify with aspirin to form prednisolone acetate in a pharmaceutical formulation matrix. 3 5 Finally, reactive reagents such as formaldehyde can attack the C-17 side chain to form the bis-methylene dioxy derivatives (BMD) 3 6 Formaldehyde is a potential impurity and/or reaction product present in such commonly used pharmaceutical adjuvants as polyethylene glycols.
.
Stability of Dexamethasone - The following reported stability information is entirely consistent with the potential reactivity discussed above. Dexamethasone solid is reported to be stable in air13 but should be protected from light.’ Solutions o f dexamethasone lose about 50% of the C - 1 7 a-ketol side chain within 6-8 minutes in the presence of a base catalyst.17 Excellent stability is shown by dexamethasone in a variety of marketed pharmaceutical dosage forms.2 Wahba has compared the thermal stability of dexamethasone in four different tablet formulations. l 7
5. Methods of Analysis 5.1 Reference Standards Both the U.S.P. and B.P. supply standard samples of dexamethasone. A highly purified sample of dexamethasone was prepared by equilibrating dexamethasone with ethyl acetate. l6 Merck Standard # 8 4 1 5 - 7 6 , which was prepared as described above, had a phase splubility analysis slope of 0.1% ? 0.1 in ethyl acetate. 5 . 2 A-Ring Analysis (without derivatization)
Ultraviolet Absorption
-
Direct measurement of the
U.V. absorbance at the X maximum - 2 4 0 nm. is an official physical measurement in both the U.S.P. and B.P. In addition, U.V. absorption has been used as an analytical measurement for dexamethasone after previous separation techniques such as liquid partition and/or chromatography have been employed to isolate dexamethasone from a pharmaceutical matrix. 9 39 Non-specif ic interference in the U . V .
184
OE XAMETHASONE
measurements may sometimes b e e l i m i n a t e d by a d i f f e r e n t i a l t e c h n i q u e i n w h i c h a s t r o n g r e d u c i n g a g e n t , s u c h as boroh y d r i d e , c o n v e r t s t h e A1y4-3 k e t o chromophore t o a s a t u r a t e d s y s t e m d e v o i d of a b s o r b a n c e a t a b o u t 240 nm.40 D e t e r m i n a t i o n of t h e U.V. a b s o r b a n c e of a n u n t r e a t e d a l i q u o t v e r s u s a r e d u c e d a l i q u o t y i e l d s i n f o r m a t i o n on t h e s t e r o i d U . V . a b s o r b a n c e i n t h e p r e s e n c e of e x t r a n e o u s absorbance. The f e a s i b i l i t y o f t h i s a p p r o a c h was r e c e n t l y d e m o n s t r a t e d f o r b e t a m e t h a ~ o n e . ~I ~ t s h o u l d be n o t e d t h a t A4-3 k e t o s t e r o i d s e x h i b i t t h e same U . V . a b s o r b a n c e b e h a v i o r a s t h e A1y4-3 k e t o s t e r o i d s and d i r e c t measurements c a n n o t d i s t i n g u i s h b e t w e e n them. The j u d i c i o u s u s e o f b o r o h y d r i d e r e d u c t i o n may e n a b l e o n e t o m e a s u r e L4-3 k e t o i m p u r i t i e s i n t h e p r e s e n c e o f A1'4-3 k e t o s t e r o i d s s u c h a s dexamethasone. N . M . R . Measurements - An N . M . R . a s s a y method f o r b o t h b u l k d r u g and f o r m u l a t i o n s b a s e d on m e a s u r i n g t h e i n t e n s i t y o f t h e r o t o n s i g n a l from t h e C - 1 p r o t o n a t a b o u t 2 . 1 Tau f o r A1y9-3 k e t o s t e r o i d s i n c l u d i n g dexamethasone w a s rec e n t l y d e s c r i b e d . 42 The t e c h n i q u e a p p e a r s t o b e c a p a b l e o f m e a s u r i n g b o t h 0-1-3 k e t o and A194-3 k e t o compounds s e p a r a t e l y o r t o g e t h e r i n t h e same s a m p l e . The r e l a t i v e l y h i g h l e v e l s of d r u g r e q u i r e d f o r a n a l y s i s (80-100 mg.1 s a m p l e ) w i l l limit a p p l i c a t i o n of t h e p r o c e d u r e as d e s cribed without appropriate modifications t o increase the a s s a y s e n s i t i v i t y by a t l e a s t two o r d e r s of m a g n i t u d e .
P o l a r o g r a p h y - The p o l a r o g r a p h i c d e t e r m i n a t i o n of dexamethasone i n t a b l e t d o s a g e Lorms i n 80% e t h a n o l , pH 4 . 2 FlcIlvaine b u f f e r has been The r e d u c t i o n s t e p e x h i b i t e d by Alr4-3 k e t o s t e r o i d u s u a l l y o c c u r s a t more a n o d i c p o t e n t i a l s , and i s e a s i l y d i s c e r n i b l e from t h e r e d u c t i o n s t e p e x h i b i t e d by t h e c o r r e s p o n d i n g C4-3 k e t o s t e r o i d s . 4Lt A-King A n a l y s i s ( w i t h d e r i v a t i z a t i o n ) Hydrazone F o r m a t i o n - I s o n i c o t i n i c a c i d h y d r a z i d e (INH) r e a c t s w i t h t h e A-ring c a r b o n y l t o p r o d u c e a y e l l o w h y d r a z o n e . 1 3 A number of s u b s t a n c e s t h a t i n t e r f e r e w i t h Recently, t h e I N H a s s a y a r e d i s c u s s e d i n R e f e r e n c e 39. T a i s h o h a s recommended t h e u s e o f INH-2HC1 r a t h e r t h a n I N H
IS5
EDWARD M. COHEN
i t s e l f as a r e a g e n t f o r t h e d e t e r m i n a t i o n of dexamethasone. 4 5 It is anticipated t h a t other carbonyl reagents w i l l likew i s e p r o v i d e a b a s i s f o r a n a l y t i c a l methodology w i t h dexamethasone. F o r i s t and Johnson d i s c u s s a number of t h e s e . 4 6
The i n t e g r i t y of t h e A-ring of s t e r o i d s i s g e n e r a l l y cons i d e r e d t o be r e l i a b l y d e t e r m i n e d by e i t h e r U.V. o r I N H a s s a y . 3 9 , 4 7 I n view of t h e r e p o r t e d p r o d u c t s of A-r ng p h o t o l y s i s of p r e d n i s o n e h a v i n g c1,B u n s a t u r a t e d k e t o n e s t r u c t u r e s ( s e e S e c t i o n 4 ) , which may i n t e r f e r e i n t h e measurement of t h e u n a l t e r e d A-ring s t e r o i d , c a u t i o n i n u s i n g t h e s e measurements s h o u l d b e e x e r c i s e d . I t i s i n t e r e s t i n g t o n o t e t h a t d a t a p r e s e n t e d i n R e f e r e n c e 47 s u g g e s t t h a t b o t h d i r e c t U . V . a n d / o r I N H a s s a y gave h i g h e r r e s u l t s f o r p h o t o l y z e d s o l u t i o n s of p r e d n i s o n e (A1y4-3 k e t o s t e r o i d ) t h a n d i d a q u a n t i t a t i v e p a p e r c h r o m a t o g r a p h i c a s s a y of t h e same s o l u t i o n s .
5 . 3 B-Ring A n a l y s i s There a r e no l i t e r a t u r e r e p o r t s t h a t d e a l s p e c i f i c a l l y w i t h a s c e r t a i n i n g t h e i n t e g r i t y of t h e 9 a - f l u o r o s u b s t i t u e n t i n dexamethasone.
5 . 4 C-Ring A n a l y s i s While t h e r e a r e no s p e c i f i c r e p o r t s c o n c e r n i n g dexamethasone, a number of p r o c e d u r e s based on t h e r e a c t i v i t y of t h e oxygen f u n c t i o n a t C - 1 1 a r e d i s c u s s e d by F o r i s t and Johnson f o r r e l a t e d s t e r o i d s . 4 6
5 . 5 D-Ring A n a l y s i s The a - k e t o l group (CH20H-CO) p o s s e s s e s r e d u c i n g p r o p e r t i e s and i t s r e a c t i v i t y towards b l u e t e t r a z o l i u m (B.T.) i s u t i l i z e d e x t e n s i v e l y as a n a s s a y p r o c e d u r e f o r dexamethasone.39 Both t h e U.S.P. and B.P. employ t h e B.T. a s s a y f o r dexamethasone. However, t h e U.S.P. u t i l i z e s a p r i o r t h i n l a y e r c h r o m a t o g r a p h i c s e p a r a t i o n which i n c r e a s e s t h e s e l e c t i v i t y and s p e c i f i c i t y o f t h e f i n a l B.T. a s s a y measurement f o r i n t a c t dexamethasone. The p r e s e n c e o f
I86
DEXAMETHASONE
e a s i l y o x i d i z e d e x c i p i e n t s can cause i n t e r f e r e n c e i n t h e B . T . a s s a y p r o c e d u r e . A t a b u l a t i o n o f a number o f s u c h i n t e r f e r e n c e s i s g i v e n i n R e f e r e n c e 39. Both p o s i t i v e and n e g a t i v e i n t e r f e r e n c e s a r e p o s s i b l e . The f o r m e r a r e d u e t o a g e n t s w h i c h a r e o x i d i z e d u n d e r t h e c o n d i t i o n s of t h e B.T. r e a c t i o n . The l a t t e r a r e a g e n t s w h i c h c a n a l t e r t h e pH o f t h e a l k a l i n e B.T. r e a c t i o n m i x t u r e t h e r e b y d e c r e a s i n g t h e e x t e n t of c o l o r formation. E f f e c t i v e e l i m i n a t i o n of i n t e r f e r e n c e s c a n o f t e n b e a c h i e v e d by s e l e c t i v e e x t r a c t i o n and chromatographic procedures. An a u t o m a t e d B.T. a s s a y h a s b e e n d e s c r i b e d f o r dexamethasone t a b l e t s . 4 8 The 1 7 , 2 1 - d i h y d r o x y - 2 0 - k e t o g r o u p of d e x a m e t h a s o n e r e a c t s w i t h phenylhydrazine-sulfuric a c i d ( P o r t e r - S i l b e r ) r e a g e n t t o form a y e l l o w chromogen s u i t a b l e f o r a s s a y p u r p o s e s . 3 9 A s i n t h e c a s e o f t h e B.T. a s s a y , a number o f s p e c i f i c c o l o r i n t e r f e r e n c e s , which c a n a r i s e from t h e r e a c t i o n o f t h e r e a g e n t w i t h e x c i p i e n t s , may b e e l i m i n a t e d by s e l e c t i v e e x t r a c t i o n and c h r o m a t o g r a p h i c p r o c e d u r e s . A number of o t h e r a s s a y a p p r o a c h e s b a s e d on t h e r e a c t i v i t y of t h e i n t a c t C-17 s i d e c h a i n d e s c r i b e d f o r r e l a t e d stero i d s are presumably a p p l i c a b l e t o dexamethasone; These i n c l u d e : a ) 2,4-dinitrophenylhydrazine r e a g e n t 49 - t h i s r e a g e n t was f o u n d t o b e a p p r o x i m a t e l y t w i c e as s e n s i t i v e a s B . T . a s s a y f o r p r e d n i s o n e b u t i s n o t q u i t e as s e l e c t i v e a s B . T . r e a g e n t f o r i n t a c t p r e d n i s o n e i n t h e p r e s e n c e o f deg r a d a t i o n p r o d u c t s ; b ) formaldehyde e s t i m a t i o n f o l l o w i n g p e r i o d a t e o r b i s m u t h a t e o x i d a t i o n . 46
The u s e o f any o f t h e a s s a y p r o c e d u r e s d e s c r i b e d above a s a n a b s o l u t e i n d e x o f d e x a m e t h a s o n e i n t e g r i t y i n a pharmac e u t i c a l m a t r i x s h o u l d n o t b e assumed w i t h o u t i n d e p e n d e n t v e r i f i c a t i o n u t i l i z i n g h i g h r e s o l u t i o n mass t r a n s p o r t p r o c e d u r e s s u c h as t h i n l a y e r c h r o m a t o g r a p h y , b e c a u s e o f t h e complex n a t u r e of t h e c h e m i c a l c h a n g e s p o s s i b l e a t t h e C - 1 7 s i d e chain. For e x a m p l e , a TLC s e p a r a t i o n of a s a m p l e m i x t u r e f o l l o w e d b y a d e m o n s t r a t i o n of t h e a b s e n c e o f c o l o r r e s p o n s e t o a p a r t i c u l a r r e a g e n t of a l l f o r e i g n s p o t s , s a v e f o r i n t a c t d e x a m e t h a s o n e , would l e n d a s s u r a n c e as t o t h e s p e c i f i c i t y of t h a t reagent.
187
E D W A R D M. COHEN
5.6 Infrared Analysis B e l l ~ m o n t ed~e s~c r i b e d a s o l i d s t a t e I R a s s a y p r o c e d u r e (KBr m u l l ) f o r m e a s u r i n g d e x a m e t h a s o n e i n t h e p r e s e n c e of t r i a m c i n o l o n e u t i l i z i n g as a n a l y t i c a l w a v e l e n g t h s 915 cm.-' and 1140 c m . - l .
5.7 Fluorescence A n a l y s i s U n l i k e A4-3 k e t o s t e r o i d s , t h e A1,4-3 k e t o compounds do n o t e x h i b i t s i g n i f i c a n t s u l f u r i c a c i d induced f l u o r e s cence. 5 1 Recently, a f l u o r e s c e n t assay f o r c o r t i c o s t e r o i d s w a s d e s c r i b e d b a s e d on making a f l u o r e s c e n t D-ring d e r i v a t i v e . 66
5 . 8 Mass T r a n s p o r t T e c h n i q u e s Assay p r o c e d u r e s d e s c r i b e d below depend on t h e s e l e c t i v e m i g r a t i o n o f e i t h e r t h e i n t a c t m o l e c u l e o r a rec o g n i z a b l e d e r i v a t i v e o f t h e i n t a c t molecule between phases f o l l o w e d by a s p e c i f i c f u n c t i o n a l g r o u p o r n o n - s p e c i f i c q u a n t i t a t i v e measurement f o r t h e m o l e c u l e i n t h e a p p r o p r i a t e phase. Phase S o l u b i l i t y A n a l y s i s - See S e c t i o n 5.1 f o r d i s c u s s i o n of a p h a s e s o l u b i l i t y s y s t e m f o r d e x a m e t h a s o n e . L i q u i d - L i q u i d E x t r a c t i o n - S e p a r a t i o n of i n t a c t a d r e n o c o r t i c o s t e r o i d s from a c i d i c d e c o m p o s i t i o n p r o d u c t s h a s b e e n a c c o m p l i s h e d by p a r t i t i o n i n g a s a m p l e b e t w e e n a n e u t r a l o r s l i g h t l y a l k a l i n e a q u e o u s p h a s e and c h l o r o f o r m . 3 1 y 3 9 A v e r y u s e f u l d i s c u s s i o n of t h e i n t e r p r e t a t i o n o f d i f f e r e n c e s n o t e d f o r s t e r o i d c o n t e n t of s a m p l e s o b t a i n e d by B . T . , P o r t e r - S i l b e r , I N H and U . V . a s s a y i s g i v e n i n R e f e r e n c e 39. Column Chromatography - The u s e of h i g h p r e s s u r e l i q u i d c h r o m a t o g r a p h y as a c o n v e n i e n t s t a b i l i t y i n d i c a t i n g a s s a y procedure f o r t h e a n a l y s i s o f c o r t i c o s t e r o i d creams and o i n t m e n t s w a s r e c e n t l y d e m o n s t r a t e d . 5 2 The a u t h o r s show a s a m p l e chromatogram o b t a i n e d f o r d e x a m e t h a s o n e u s i n g a column of 6,R l - o x y d i p r o p i o n i t r i l e on Z i p a x and 1%e t h a n o l i n hexane a s a m o b i l e p h a s e a t 500 p . s . i . ( e l u t i o n t i m e -11 m i n u t e s ) . A g e n e r a l i z e d s y s t e m f o r t h e p r e d i c t i o n o f
I88
DEXAMETHASONE
of elution curves for corticosteroids based on partition coefficients for a hexane-chloroform-dioxane-water (90-1040-5) solvent system on diatomaceous earth was also des~ r i b e d . The ~ ~ authors give data for betamethasone. A column partition system has been described by Graham which can effectively trap the corticosteroid in an acetonitrile layer on a diatomaceous earth column whi1.e interferences are removed by washing with heptane. 54 Acetonitrile and corticosteroids are then removed from the column with chloroform. The method may be modified readily for the removal of acidic, basic, and/or water soluble interferences. Data are given for both formulated and unformulated dexamethasone. Paper Chromatography - Johnson and Fowler give Rf data for dexamethasone and related steroids utilizing the following system: 5 5 Whatman No. 1 impregnated with 40% V / V formamide in methanol. Mobile Phase: Saturated solution of formamide in chloroform. Mode of Operation: Descending development for 35 cm in a saturated tank. Detection: Diphenyl styryl phenyl tetrazolium t heat = violet spots for steroids. Stationary Phase:
Compound Betamethasone Cortisone Dexamethasone Hydrocortisone Prednisolone Prednisone
Rf .16 .62 .21 .26 .15 .55
Thin Layer Chromatography (TLC) - U.S.P. XVIII utilizes TLC as both a qualitative and quantitative assay procedure for dexamethasone. l 3 N . F . XI11 employs TLC as an identity test for dexamethasone in official dosage forms. Wahba has demonstrated the utility of quantitative TLC as a stability indicating approach to the estimation of dexamethasone in aged samples of experimental tablet formulations.” There is little doubt that TLC offers the analyst
’‘
EDWARD M. COHEN
a n e x c e l l e n t h i g h l y s e l e c t i v e method, u s u a l l y w i t h o u t req u i r i n g any d e r i v a t i z a t i o n , f o r a s s e s s i n g t h e i n t e g r i t y o f dexamethasone i n common p h a r m a c e u t i c a l m a t r i c e s . Thin l a y e r chromatography c a n o f t e n f u n c t i o n as a p r i m a r y o r r e f e r r a l a s s a y p r o c e d u r e t o c o r r o b o r a t e t h e v a l i d i t y of a non-chromatographic a s s a y p r o c e d u r e . Some of t h e r e p o r t e d TLC d a t a f o r dexamethasone, i n a d d i t i o n t o t h e i n f o r m a t i o n i n t h e U.S.P. and N.F., are g i v e n i n T a b l e 11. O t h e r TLC s y s t e m s f o r dexamethasone a r e d i s c u s s e d i n R e f e r e n c e s 1 7 , 59 and 60. Of s p e c i a l i n t e r e s t i s a r e p o r t which d e s c r i b e s t h e s e p a r a t i o n of dexamethasone from b e t a m e t h a s o n e . 6 1 Gas Chromatography - S t e r o i d s p o s s e s s i n g t h e C-17 d i h y d r o x y a c e t o n e s i d e c h a i n u s u a l l y undergo m o l e c u l a r a l t e r a t i o n a f t e r a p p l i c a t i o n t o GLC columns t o y i e l d as a major product t h e corresponding 1 7 - k e t o s t e r o i d . 62 Approaches t o a t t a i n q u a n t i t a t i v e c o n v e r s i o n t o a s u i t a b l e n o n - l a b i l e d e r i v a t i v e o f s t e r o i d s r e l a t e d t o dexamethasone have been r e c e n t l y d e s c r i b e d by B a i l l i e and co-workers. 6 3 One o f t h e most s t a b l e d e r i v a t i v e s s u i t a b l e f o r g a s chromat o g r a p h y i s t h e 20-0-methyloxime-17,2l-trimethylsilyl ether of t h e a d r e n o c o r t i c o s t e r o i d . 6 . Metabolism and P h a r m a c o k i n e t i c s Normal human s u b j e c t s g i v e n 1 . 6 mcg. o f 1,2,4-3H dexamethasone o r a l l y e x c r e t e d a b o u t 15% of t h e t o t a l r a d i o a c t i v i t y i n the urine within four hours a f t e r administrat i o n . 6 4 Approximately 50% of t h e e x c r e t e d r a d i o a c t i v i t y was i n c o n j u g a t e d form, presumably a g l u c u r o n i d e and 50% o f t h e e x c r e t e d r a d i o a c t i v i t y was i n non-conjugated form. The u r i n a r y l e v e l s o f t o t a l and c o n j u g a t e d dexarnethasone i n p a t i e n t s on c h r o n i c d i p h e n y l h y d a n t o i n t h e r a p y were s i g n i f i c a n t l y i n c r e a s e d compared t o t h e l e v e l s shown by n o r m a l human s u b j e c t s . I n a n o t h e r s t u d y , t h e mean r e c o v e r y of u r i n a r y r a d i o a c t i v i t y a f t e r f o u r h o u r s and 24 h o u r s was 16% and 64%, res p e c t i v e l y € o r d o s e s of 0.5 t o 1 . 5 mg. of l a b e l e d dexamethasone a d m i n i s t e r e d i n t r a v e n o u s l y as a s o l u t i o n i n s a l i n e t o human s u b j e c t s . 6 0 The m a j o r pathway of dexamethasone metabolism, f o l l o w i n g I . V . a d m i n i s t r a t i o n , a p p e a r s t o i n v o l v e formation of p o l a r unconjugated d e r i v a t i v e s . A
190
TABLE I1
Silica Gel G a Solvent: Rf:b Reference: aA
.51d
D 1.40d
.EOd
58
58
58
C
A
1.00' 57
.;2d 58
I .i5d 58
.t5d 58
.:2d 58
.50d 58
J d
.67 58
Methylene Ch1oride:dioxane:water (100:50:50) - lower layer; Chloroform-ethanol (9:l); C = Chloroform-90% methanol (9:l); D = Cyclohexane-ethyl acetate (1:l); E = Chloroform-acetone (9 :1) ; F = Chloroform-acetone ( 4 : l ) ; G = C y c l o h e x a n e - c h l o r o f o r m - a c e t i c acid (7:2:1); H = Methylene chloride-acetone ( 4 : 1); I = Chloroform-acetic acid (9:l); J = Kethylene chloride-acetic acid (9: 1).
B
= =
bDexamethasone separated from other related steroids. Reference 58 also includes TLC data for dexamethasone on aluminum oxide and magnesium silicate stationary phases as well as useful information on detection system. C
Relative to hydrocortisone
=
1.00.
dRelative to cortisone = 1.00.
E D W A R D M. COHEN
t% of 252 m i n u t e s was n o t e d f o r t h e e l i m i n a t i o n of i n t a c t dexamethasone from plasma. I t i s a n t i c i p a t e d t h a t development of a p p r o p r i a t e s e n s i t i v e a s s a y s f o r dexamethasone w i l l e n a b l e s t u d i e s i n human subj e c t s t o be c a r r i e d out using conventional pharmaceutical dosage f o r m s , made w i t h “ c o l d ” dexamethasone, t o y i e l d a d d i t i o n a l i n f o r m a t i o n on t h e o r a l b i o a v a i l a b i l i t y o f dexamethasone. C u r r e n t a n a l y t i c a l methodology f o r dexamethas o n e i s n o t s u f f i c i e n t l y s e n s i t i v e t o a s s a y a t t h e nanogram p e r m l . l e v e l , which r e p r e s e n t s e x p e c t e d plasma c o n c e n t r a t i o n s f o l l o w i n g o r a l a d m i n i s t r a t i o n of t h e r a p e u t i c d o s e s o f dexamethasone. Techniques such as r a d i o i m m u n ~ a s s a y ~a r e l i k e l y t o p r o v i d e t h e a s s a y s e n s i t i v i t y and s e l e c t i v i t y req u i r e d f o r t h e s e s t u d i e s i n t h e p r e s e n c e of t h e normal s t e r o i d background i n b i o l o g i c a l f l u i d s .
A p r o c e d u r e f o r t h e d e t e c t i o n and i d e n t i f i c a t i o n of dexamethasone i n h o r s e u r i n e h a s been d e s c r i b e d and h a s a s e n s i t i v i t y l i m i t of 2 mcg. p e r m l . o f u r i n e t a k e n f o r
a n a l y s i s . 5’
192
DEXAMETHASONE
7 . References 1. "Merck I n d e x " , E i g h t h E d . , Merck a n d C o . , Rahway, N . J . , 1 9 6 8 , p . 334.
2 . B i l e s , J . A . , J. Pharm.
K.,50,
Inc.,
464 (1.961).
3. McCaul ey, J., Merck S h a r p and Dohme R e s e a r c h L a b o r a t o r i e s , Rahway, N.J., P e r s o n a l Communic a tion. 4 . M e s l e y , R . J., S p e c t r o c h i m .
G., 22, 889
(1966).
5. M e s l e y , R. J . , a n d J o h n s o n , C. A . , J. Pharm. Pharma__ col.,
17,329
(1965).
6 . C l a r k e , E. G. C . , " I s o l a t i o n a n d I d e n t i f i c a t i o n s o f Drugs", P h a r m a c e u t i c a l P r e s s , London, p . 2 8 7 , 737 ( 1 9 6 9 ) . 7. D o u g l a s , A . W. a n d S i n g l e t o n , B . , Merck S h a r p a n d Dohme R e s e a r c h L a b o r a t o r i e s , Rahway, N . J . , P e r s o n a l Communication. 8 . N o u d e r t , H. a n d Ropke, H . , " A t l a s o f S t e r o i d S p e c t r a " , S p r i n g e r - V e r l a g , New York, 6 2 1 ( 1 9 6 5 ) . 9 . B r i t i s h P h a r m a c o p e i a , P h a r m a c e u t i c a l P r e s s , London, p . 295 ( 1 9 6 8 ) .
1 0 . McCauley, J., Merck S h a r p a n d Dohme R e s e a r c h L a b o r a t o r i e s , Rahway, N.J., P e r s o n a l Commu nic a tion. 11. Downing, G . V . , Merck S h a r p a n d Dohme R e s e a r c h Labo r a t o r i e s , Rahway, N . J . , P e r s o n a l Com m unic a tion. 1 2 , S a d g e , W., R i e g e l m a n , S . a n d .Johnson, L . F . , S t e r o i d s , 595 ( 1 9 7 1 ) .
17,
13. U . S . P . (1970).
X V I I I , Mack P u b l i s h i n g C o . , E a s t o n , P a . ,
1 4 . Dempski, K. E., P o r t n o f f , J . 13. a nd Wase, A . I d . , Pharm. S c i . , E, 579 ( 1 9 6 9 ) .
_
c
_
_
174
~J
EDWARD M. COHEN
15. K a b a s a k a l i a n , P . , B r i t t , E . ,
Pharm. -S c i . , 55,
and Y u d i s , M. D . ,
2.
642 (1966).
1 6 . S m i t h , G . , Merck S h a r p and Dohme R e s e a r c h L a b o r a t o r i e s Rahway, N . J . , P e r s o n a l Communication. 1 7 . Wahba, S . K . , Amin, S. W. and R a f a e l , N., J. Pharm. 1 2 3 1 (1968).
S c i . , 57,
2, 1045
18. Lodge, B. A. and T o f t , P . , J. Pharm. S &., (1970). 19. Lodge, B. A. and T o f t , P . , 1 9 6 (1970).
J.
23,
Pharm. Pharmacol.,
20. Albers-Schonberg, G . , tierck S h a r p and Dohme R e s e a r c h L a b o r a t o r i e s , Rahway, N . J . , P e r s o n a l Communication.
2 1 . F i e s e r , L. F. and F i e s e r , M. , " S t e r o i d s " , P u b l i s h i n g Co., New York, p. 694-695 (1959). 22. A r t h , G . E . , (1958).
et al.,
Reinhold
=.,80, 3161
2. Am. E.
23. A r t h , G . E . , U.S. P a t e n t # 3 , 3 7 5 , 2 6 1 ( 1 9 6 8 ) . 24. O l i v e t o , E. P . , (1958).
et al.,
2. &.
Chem. SOC.,
80,
4431
25. Mertel, H. E . , G e r b e r , A. N. and M e r i w e t h e r , H . T., J . Labeled Compounds, V I , 250 (1970).
26. B a r t o n , D. H. R. and T a y l o r , W. C . , J. Chem. S O C . , 2500 (1968). 27. Smith, G. B.
,
et al.
, J. Pharm.
28. Bush, I . E. and Mahesh, V . B . , (1958). 29. B r e n n e r , G . , (1969).
s., 61, 708 Biochem.
J.,69, 9
e t a l . , Angew, Chem. (Engl. E d . ) ,
194
(1972).
8,
975
DEXAMETHASONE
3 0 . W e n d l e r , N. L . , " M o l e c u l a r R e a r r a n g e m e n t s " , e d i t e d b y P. Mayo, I n t e r s c i e n c e , New Y o r k , P a r t ' h o , 1 0 6 8 ( 1 9 6 7 ) .
31. G u t t m a n , D . E. a n d Meister, P. O . , Assoc. Ed., 4 7 , 773 ( 1 9 5 8 ) .
s.
J. Am. - Pharm. -
32. C o n b e r e , J . P . , U . S . P a t e n t 8 3 , 7 7 3 , 0 7 7 ( 1 9 5 6 ) .
33. W e n d l e r ,
e., p . 1119.
9.
34. S m i t h , L. L . ,
e t a l . , J. A".
e. z., 82, 4676
(1960). 35. Meister, P. D . , 4 7 -, 5 7 6 ( 1 9 5 8 ) .
et al.,
2. E .
3 6 . F i e s e r , L . F. a n d F i e s e r , M . ,
Pharm. A S S O C . ,
&.
c & . ,
s. Ed.
p . 697.
3 7 . U n p u b l i s h e d Data, Merck S h a r p a n d Dohme R e s e a r c h L a b o r a t o r i e s , West P o i n t , P a .
38. Z a b r i s k i e , J . , P e r s o n a l C o m m u n i c a t i o n , Merck S h a r p a n d Dohme, West P o i n t , P a . 3 9 . Graham, R. E . , W i l l i a m s , P . A . , a n d K e n n e r , C. T . , S c i . , 59, 1 1 5 2 ( 1 9 7 0 ) .
J . -Pharm. -
Pharrn. Sci., 4 0 . C h a f e t z , L . , J. -
60,
335 ( 1 9 7 1 ) .
4 1 . C h a f e t z , L . , T s i l i f o n i s , D . C . a n d R i e d l , J . M., Pharm. _ _ _ -S c i . , 61, 1 4 8 ( 1 9 7 2 ) .
2
42. A v d o n o v i c h , H. W . , H a n b u r y , P . a n d Lodge, B. A . , Pharm. Sci., 1164 (1970). --
2.
2,
4 3 . I m r 6 n 6 , B. a n d M i h a l y n e , M . ,
Gyogysz.,
4 4 . K a b a s a k a l i a n , P. a n d M c G l o t t e n , J . , J.
78, 5 0 3 2 ( 1 9 5 6 ) .
14,97
5. e. SOf.,
4 5 . T a i s h o , K . T . , e t a l . , Chem. Pharm. B u l l . , (1972).
105
(1970).
20, 5 8 9
E D W A R D M. COHEN
46. F o r i s t , A. A. and J o h n s o n , J. L . i n " P h a r m a c e u t i c a l A n a l y s i s " , e d . H i g u c h i , T. and Brochmann-Hanssen, E r , I n t e r s c i e n c e , New York, 1961, pp. 71-85. 47. Hamlin, W. 4 9 , 253 ( 1 9 6 0 ) .
E.,
et &., J . &.
48. Brower, J . F . , J. (1969).
Ass.
_
L
-
60,
Super. S a n i t a , 12370h, 1962.
51. Noujaim, A . A. and J e f f e r y , D. A . ,
842
1539 (1971).
m.&.
58,
52,
O f f i c . Anal. Chem.,
&., 49. Woodson, A . L . , J. Pharm. S 50. Bellomonte, G . , (1962 ; Chem. A b s t . ,
g . Ed.,
Pharm. ASSOC.,
25, 581
Can. 2.
Pharm.
g.
5 , 26 (1970).
52. M o l l i c a , J . A. and S t r u s z , R. F . , 444 (1972). 53. Weber, D. J . , e t a l . ,
5 4 . Graham, R. E . , e t a l . ,
J. Pharm.
2.
Pharm.
g., 5,
s., 61, 689
(1972).
2. P h a r m. S c i . , 2, 1473
(1970)
55. Johnson, C. A . and Fowler, S . , J . Pharm. P h a r m a c o l . , 17T (1964).
1 6 , Supp.
56. N.F. X I I I , American Pharm. A S S O C . , Washington, 1970, pp. 208-209. 57. H o l l , A . , J . Pharm. Pharmacol.,
16,Supp.
9T ( 1 9 6 4 ) .
58. K i r s c h n e r , J. G . , "Thin-Layer Chromatography", s c i e n c e , New York, 1 9 6 7 , pp. 596-599.
Inter-
59. Moss, M. S . and R y l a n c e , H. J . , J. Pharm. P h a r m a c o l . , 18, 1 3 (1966). 60. Haque, N . ,
et al.,
2.
C l i n . Endocr.,
34, 44
(1972).
61. S c a v i n o , C . and C h i a r a m o n t i , D . , J. Pharm. B e l g . , 204 (1965).
20,
DEXAMETHASONE
6 2 . VandenHeuvel, W. J. A . i n "Theory a n d A p p l i c a t i o n s o f Gas C h r o m a t o g r a p h y in I n d u s t r y a n d M e d i c i n e " , e d . b y Kroman, H . S . a n d B e n d e r , S . R . , G r e e n e a n d S t r a t t o n , N e w York, 1 9 6 8 , p p . 120-134. 6 3 . B a i l l i e , T. A., e t a l . , A n a l . Chem., _
64. Jubiz, W.,
_
_
e t a l . , New E x . J.
_
I
30 ( 1 9 7 2 ) .
x., x,11 (1970).
6 5 . I l i d g l e y , A . K. a n d N i s w e n d e r , G . D . , S u p p l . , 1 4 7 . 320 ( 1 9 7 0 ) . 6 6 . Chayen, R., e t al.,
44, Acts
Endocrinol.
G. Biocheni., 39, 5 3 3
(1971).
This Page Intentionally Left Blank
DIOCTYL SODIUM SULFOSUCCINATE
Sut Ahuja and Jerold Cohen
Reviewed by J. Kazan and T. E. Ricketts
199
S. AHUJA AND J. COHEN
CONTENTS
7. 8.
Description 1.1 Name, Formula, Molecular Weight, Elemental Composition 1 . 2 Appearance, Color, Odor Physical Properties 2.1 Infrared Spectrophotometry 2.2 Nuclear Magnetic Resonance 2.3 Mass Spectrometry 2 . 4 Differential Thermal Analysis 2.5 Thermogravimetric Analysis 2.6 Differential Scanning Calorimetry 2.7 Solubility 2.8 Solubilization 2.9 Effect On Surface Tension of Liquids 2.10 Crystal Properties Synthesis Stability Met abu 1ism Methods of Analysis 6 . 1 Titrimetric Analysis 6.2 Colorimetric Analysis 6 . 3 Infrared Analysis 6 . 4 Turbidimetric Analysis 6 . 5 Determination of Micellar Weight 6.6 Thin-Layer Chromatography References Acknowledgements
1.
DESCRIPTION
1.
2.
3. 4. 5.
6.
Name, Formula, Molecular Weight, Elemental Composition Chemically, dioctyl sodium sulfosuccinate is sulfosuccinic acid bis(2-ethylhexyl) ester S-sodium salt or sodium 1, 4-bis(2-ethylhexyl) sulfosuccinate o r bis(2-ethylhexyl) sodium sulfosuccinate. It is also known as sodium dioctyl sulfosuccinate; DSSj Aerosol OT; Alphasol OT; Colace; Complemix; Coprol; Dioctylal; Dioctyl-Medo Forte; Diotilan; Diovac; Disonate; Doxinate; Doxol; Dulsivac; Molatoc; Molofac; Nevax; Norval; Regutol; Softili; Solusol; Sulfimel DOS; Vatsol OT; Velmol and Waxsol (1). It has a molecular weight of 444.57 (C20H3707SNa). 1.1
200
DIOCTYL SODIUM SULFOSUCCINATE
0
// C2H5
CH2-C.
\
I
I
O-CH2-CH(CH2)3CH3
O-CH2 -CH (CH2) 3CH3
N a03S -CH-/
I
%
C2H5 0
The t h e o r e t i c a l e l e m e n t a l c o m p o s i t i o n of d i o c t y l s u l f o s u c c i n a t e is a s follows: Carbon 54.03% Hydrogen 8.39% Oxygen 25.19% Sulfur 7.21% Sodium 5. 17% 1.2
Appearance, C o l o r , Odor D i o c t y l sodium s u l f o s u c c i n a t e i s g r a y i s h t o w h i t e , w a x - l i k e , p l a s t i c s o l i d , h a v i n g a c h a r a c t e r i s t i c odor sugg e s t i v e of o c t y l a l c o h o l .
2.
PHYSICAL PROPERTIES
2.1
I n f r a r e d Spectrophotometry The i n f r a r e d s p e c t r u m ( 2 ) o f a 5% c h l o r o f o r m s o l u t i o n o f d i o c t y l sodium s u l f o s u c c i n a t e r e c o r d e d w i t h a P e r kin-Elmer I n f r a r e d S p e c t r o p h o t o m e t e r , Model 225 i s shown i n F i g u r e 1. Band a s s i g n m e n t s f o r t h e s p e c t r u m i n 5% c h l o roform s o l u t i o n a r e l i s t e d i n T a b l e I .
2.2
N u c l e a r M a g n e t i c Resonance The NMR s p e c t r u m ( 3 ) of d i o c t y l sodium s u l f o s u c c i n a t e ( F i g u r e 2 ) was r e c o r d e d i n DMSO-db on a v a r i a n A60 ~ O M H Z NMR s p e c t r o m e t e r . S t r u c t u r a l assignments f o r t h e NMR s i g n a l s a r e t a b u l a t e d i n T a b l e 11. 2.3
Mass S p e c t r o m e t r y R e l i a b l e mass s p e c t r a l d a t a ( 4 ) c o u l d n o t be obt a i n e d f o r d i o c t y l sodium s u l f o s u c c i n a t e a s t h e s p e c t r u m changes with temperature, i n d i c a t i n g thermal degradat i on.
20 1
S. AHUJA AND J. COHEN
202 rl
w
.PI
h
0
C
0
3
u
v)
I n f r a r e d Spectrum of a 5% chloroform s o l u t i o n of D i o c t y l Sodium S u l f o s u c c i n a t e 0
W
rl
H
FIGURE I.
. ..
FIGURE 2.
.. .
~~
..
Nuclear Magnetic Resonance Spectrum in DMSO-d6 of Dioctyl Sodium Sulfosuccinate
S. AHUJA AND J. COHEN
TABLE I INFRARED BAND ASSIGNMENTS FOR DIOCTYL SODIUM SULFOSUCCINATE I N 5% CHLOROFORM SOLUTION
W av enumbe r ( cm2960, 2935, 2865 1728 1465 1391, 1381 1245 1200 1048
A s s ignmen t a l i p h a t i c C H 2 ; CH3 C = O a l i p h a t i c C H 2 ; CH3
CH3 asymmetric C-0-C ( e s t e r ) asymmetric s o 3 8 symmetric C-0-C ( p o s i t i o n ) c o r r e s p o n d s t o C-O-CH2 a n d / o r symmetric S O ~ B
2.4
D i f f e r e n t i a l Thermal A n a l y s i s The t h e r m a l a n a l y s i s ( 5 ) of d i o c t y l sodium s u l f o s u c c i n a t e was c o n d u c t e d on a Du P o n t Model 900 t h e r m a l ana l y z e r i n a n i t r o g e n a t m o s p h e r e . A t h e a t i n g r a t e s of 1 0 ° C / m i n u t e and 3"C/minute, t h e thermogram ( F i g u r e 3) shows no endotherm, b u t an i r r e g u l a r c u r v e a f t e r 120°C. No t r a n s i t i o n was o h s e r v e d e x c e p t foaming of t h e sample. 2.5
Thermogravimetric A n a l y s i s A sample o f d i o c t y l sodium s u l f o s u c c i n a t e ( F i g u r e 4) l o s e s w e i g h t (5) c o n t i n u o u s l y above 35°C: 3.4% between 35°C and 152"C, a p p r o x i m a t e l y 0.5% between 152°C and 220°C. Rapid w e i g h t l o s s o c c u r s above 220"C, which amounts t o a p p r o x i m a t e l y 5 . 8 % loss up t o 248°C. A r e s i d u e o f a p p r o x i m a t e l y 15% i s l e f t a t 360°C. 2.6
D i f f e r e n t i a l Scanning Calorimetry A thermogram r u n a t lO"C/minute shows two broad endotherms ( 5 ) between 119°C and 194°C ( F i g u r e 5 ) .
2.7
Solubility D i o c t y l sodium s u l f o s u c c i n a t e i s s o l u b l e i n t h e f o l l o w i n g s o l v e n t s : carbon t e t r a c h l o r i d e , petroleum e t h e r , naphtha, xylene, d i b u t y l p h t h a l a t e , l i q u i d petrolatum, 204
DIOCTYL SODIUM SULFOSUCCINATE
F I G U R E 3.
Differential Thermal Analysis in nitrogen atmosphere of Dioctyl Sodium Sulfosuccinate
Smn
*"O
50
(00
110
1 *C
FIGURE 4.
-
wh
Z!O
2SO
lcomcmo ton CllnaMtL
300 UWlL
'
'
t '350
?nEI*ocouKcs~
400
- m 4W
Thermogravimetric Analysis of Dioctyl Sodium Sulfosuccinate 205
WO'
S. AHUJA A N D J. C O H E N
1. *C (CORRECTED FOR CHROMEL ALUMEL THERYOCOUPLESI
FIGURE 5.
Differential Scanning Calorimetry thermogram of Dioctyl Sodium Sulfosuccinate
206
DIOCTYL SODIUM SULFOSUCCINATE
TABLE I1 NMR SPECTRAL ASSIGNMENTS FOR DIOCTYL SODIUM SULFOSUCCINATE
(ppm)
Multiplicity
Number of Protons
A s s ignmen t
-H 00
c€3- c-’o 2.8-3.1
undetermined
2
I
S-CH-C:’ 0
3.35
3.6-4.1
singlet
undetermined
1.8
E20
5
S -CH -C- 0- CFl2
- lo
glycerol, pine o i l , o l e i c acid, acetone, kerosene, alcohol, benzene, d i a c e t o n e a l c o h o l , methanol, e t h a n o l , i s o p r o p a n o l , sec. b u t a n o l , methyl a c e t a t e , e t h y l a c e t a t e , amyl a l c o h o l , f u r f u r y l a l c o h o l , t e t r a h y d r o f u r f u r y l a l c oho 1, PO l y e t h y 1e n e g l y c o l , c o r n o i l , and v e g e t a b l e o i l s ( 1 ) . T a b l e 111 p r e s e n t s t h e s o l u b i l i t y o f d i o c t y l sodium s u l f o s u c c i n a t e i n s e l e c t e d s o l v e n t s . The s o l u b i l i t y f i g u r e s shown do n o t i n d i c a t e t h e l i m i t s of s o l u b i l i t y , s i n c e d i o c t y l sodium s u l f o s u c c i n a t e a p p e a r s t o be v e r y h i g h l y s o l u b l e i n most organic solvents (6).
207
TABLE I11
SOLUBILITY OF D I O C T Y L SODIUM SULFOSUCCINATE (DS S ) I N SOME ORGANIC SOLVENTS$:
Method of S o l u t i o n
Specific Gravity g/ml a t 25°C Dissolving Resulting Liquid Solution
Viscosity DSS i n S o l u t i o n Percent g/100 m l b y Weight
Of
Solution (Poises) !n
1 3
c
oc
Dissolved a t Room Temp. Heated t h e n Cooled
Carbon T e t r a c h l o r i d e Petroleum E t h e r S o l v e n t Naphtha Dibutyl Phthalate Paraffin O i l
1.55 0. 688 0.864 1.03 0.881
1.31 0.950 0.701 1.07 1.00
73.8 70.1 70.5 70.7 69.5
56.4 75.0 69.8 66.1 69.5
1.65 0.65 0.65 8.84 12.9
D
I
5
> > z 0
f0
s
rn 2
: ’ 7
R e p r i n t e d by t h e c o u r t e s y of American Cyanamid Co
DI O CT Y L SODIUM SULFOSUCCINATE
D i o c t y l sodium s u l f o s u c c i n a t e d i s s o l v e s s l o w l y i n c o l d water, b u t i t s s o l u b i l i t y i n w a t e r i n c r e a s e s w i t h an inc r e a s e i n t e m p e r a t u r e , as i n d i c a t e d i n T a b l e I V . T a b l e V p r e s e n t s t h e c o n c e n t r a t i o n of e l e c t r o l y t e s o l u t i o n i n w h i c h 1% of d i o c t y l s o d i u m s u l f o s u c c i n a t e i s s o l u b l e a t a t e m p e r a t u r e o f 25°C.
TABLE I V SOLUBILITY OF DSS I N WATER9c T e m p e r a t u r e "C
Grarns/100 r n l o f Water
25 30 40
1.5 1.8 2.3 3.0 4.0 5.5
50 60
70
R e p r i n t e d by t h e c o u r t e s y o f A m e r i c a n Cyanamid Co.
~-
~~
TABLE V SOLUBILITY OF 1% DSS I N ELECTROLYTE SOLUTIONS;': C o n c e n t r a t i o n of E l e c t r o l y t e s , % NaCl
NH4CL
0.5
0.5 2.0
3.0
:;'
,.
_LJ_ I~
(NH4)2 HP04
2 . 0 k 3
U U
‘a 0
v c
w,
0
9
0
0
I u
(w
0
B. C. R U D Y AND B. 2 . SENKOWSKI
304
0 Q)
0
0
0
!c
0
d -
co
0
0
03
0 0 N
Y W
3
I):
G
W
I):
5
a w
I-
ISOCARBOXAZI D
TABLE I V
Isocarboxazid - S o l u b i l i t y Solvent
S o l u b i l i t y (mg/ml)
3A alcohol benzene ch 1o r o form 95% e t h a n o l ethyl ether methanol p e t r o l e u m e t h e r (30"-60") 2 -propano1 water
39.6 44.8 348.6 46. 8 16.5 95.1 0.2 16.5 0.8
2.11
X-ray C r y s t a l P r o p e r t i e s The x - r a y powder d i f f r a c t i o n p a t t e r n o f r e f erence standard isocarboxazid i s presented i n Table V ( 9 ) . The i n s t r u m e n t a l c o n d i t i o n s are g i v e n below: Instrumental Conditions : Ge ner al E l e c t r i c Model XRD-6 S p e c t r o g o n i o m e t e r Generator: Tube t a r g e t : Kadiation : Optics:
50 K V , 1 2 - 1 / 2 MA Copper 0 Cu Ka = 1.542 A 0. 1' D e t e c t o r s l i t M.R. S o l l e r s l i t 3" Beam s l i t 0.0007" N i f i l t e r 4" t a k e o f f a n g l e Scan a t 0 . 2 " 20 p e r m i nut e A m p l i f i e r g a i n - 16 c o a r s e , 8.7 fine Sealed proportional counter t u b e and DC v o l t a g e a t p l a t e a u , Pulse height selection EL - 5 volts; Eu - o u t , Rate meter T . C . 4 , 2000 C/S f u l l s c a l e C h a r t s p e e d 1"/5 m i nut es Pre a r e d by g r i n d i n g a t room t em#er a t u r e
Goniometer: Detector:
Recorder: Samples :
305
B. C. R U D Y A N D B. 2. SENKOWSKI
TABLE V
X-ray D i f f r a c t i o n P a t t e r n o f Isocarboxazid 0
20 9.100 12.440 13.460 14.860 15.240 17.640 18.440 19.040 20,700 21.260 21.720 23.240 23.480 23.920 24.960 25.780 27.300 28.660 29.060 29,680 29.780 30.160 30.280 32.480 34.520 34.800 35.780 36,540 37.400 37.940 38.120 38.760 39,340 40.920 41.420 41.860 42,320 43.080
d*A 9.7177 7.1151 6.5781 5.9614 5.8136 5.0276 4.8113 4.6610 4.2908 4.1790 4.0916 3.8273 3.7887 3,7200 3.5673 3.4557 3.2666 3.1146 3.0726 3.0099 3.0000 2.9630 2.9516 2.7565 2.5981 2.5779 2,5095 2.4590 2.4044 2.3714 2.3606 2.3231 2.2902 2.2053 2.1799 2,1580 2.1356 2,0996
306
I/Io** 41 5 9 13 9 5 4 16 44 9 7 15 18 28 100 9 3 5 6 1 2 2 3 4 7 7 2 4 1 1 1 -
J
I
> N
z
W
m
6 . C. RUDY AND 6 . 2 . SENKOWSKI
The r e s u l t s from an e l e m e n t a l a n a l y s i s o f r e f e r e n c e s t a n d a r d i s o c a r b o x a z i d are p r e s e n t e d i n T a b l e IV ( 1 5 ) . TABLE VI
Elemental A n a l y s i s o f I s o c a r b o x a z i d Element
% Theory
C H N
62.33 5.67 18.17
% Found
62.22 5.66 18.20
6.2
Phase S o l u b i l i t y A n a l y s i s Phase s o l u b i l i t y a n a l y s i s h a s been c a r r i e d o u t f o r i s o c a r b o x a z i d u s i n g 2-propanol a s t h e s o l v e n t . An example i s p r e s e n t e d i n F i g u r e 8 f o r r e f e r e n c e s t a n d a r d i s o c a r b o x a z i d a l o n g w i t h t h e c o n d i t i o n s under which t h e a n a l y s i s was performed ( 8 ) . 6.3
Thin Layer Chromatographic A n a l y s i s (TLC) The f o l l o w i n g TLC p r o c e d u r e i s u s e f u l f o r s e p a r a t i n g methyl 5-methyl-3-isoxazolecarboxylate and 1benzyl-3-methyl-5-aminopyrazole from i s o c a r b o x a z i d (6) Using s i l i c a g e l GF p l a t e s and e t h y l a c e t a t e : n-heptane (60:40) a s t h e s o l v e n t system, 1 . 0 mg o f t h e sample i n methanol i s s p o t t e d on t h e p l a t e and s u b j e c t e d t o a s c e n d i n g chromatography. After t h e s o l v e n t f r o n t has ascended a t l e a s t 1 2 cm, t h e p l a t e i s a i r d r i e d and examined under shortwave u l t r a v i o l e t l i g h t . I f any methyl 5-methyl-3i s o x a z o l e c a r b o x y l a t e i s p r e s e n t i t w i l l a p p e a r a s a dark s p o t a t about Rf 0 . 8 5 . Next s p r a y t h e p l a t e w i t h a f r e s h l y p r e p a r e d s o l u t i o n o f 10% FeC13:5% K3Fe(CN)6 ( 1 : l ) . I f any l-benzyl-3-methyl-5-aminopyrazole i s p r e s e n t i t w i l l a p p e a r a s a b l u e s p o t a t about Rf 0.25. The i s o c a r b o x a z i d produces a b l u e s p o t a t about Rf 0 . 6 .
.
6.4
Colorimetric Analysis 6.41
Ammonium Molybdate Reaction The i s o c a r b o x a z i d c o n t e n t i n t a b l e t s may be determined by t h e f o l l o w i n g p r o c e d u r e ( 6 ) . The t a b l e t s a r e f i n e l y ground, a p o r t i o n e q u i v a l e n t t o about 10 mg o f i s o c a r b o x a z i d i s weighed i n t o a 50 m l v o l u m e t r i c f l a s k and
310
Figure 8
t
1
/ PHASE SOLUBILITY ANALYSIS SAMPLE: SOLVENT:
w
c
ISOCARBOXAZID 2 - PROPANOL
su)pE: 0.0 %I EQUILIBRATION: 20 HRS. ot 25O C EXTRAPOLATED SOLUBILITY: 20.5 W/g af 2 - PROPANOL
e
I
0 0
25 SYSTEM
I 50
I 75
COMPOSITION: mg of SAMPLE per g SOLVENT
i -
I00
-
ffl
0
0
> D
m
0
8. C. RUDY AND 6. Z. SENKOWSKI
d i l u t e d t o volume w i t h a c e t o n e . A f t e r t horough m i xi ng, t h e s o l u t i o n i s c l a r i f i e d by c e n t r i f u g i n g and 5.0 m l i s p i p e t t e d i n t o a s t o p p e r e d f l a s k . To t h e f l a s k a r e a l s o added 1 . 0 m l o f water, 50.0 ml o f a c e t o n e , and 1 . 0 m l o f ammonium molybdate r e a g e n t ( 1 gm o f ammonium molybdate d i s s o l v e d i n 100 m l o f d i l u t e HC1). The f l a s k i s s t o p p e r e d and t h e s o l u t i o n mixed and t h e n a l l o w e d t o s t a n d 30 m i n u t e s w i t h o c c a s i o n a l s w i r l i n g . The abs or ba nce o f t h i s s o l u t i o n i s d e t e r m i n e d a t 420 nm a g a i n s t a b l a n k . Reference standard isocarboxazid i s prepared a t approximately t h e same c o n c e n t r a t i o n and i n a s i m i l a r manner as above. The mg o f i s o c a r b o x a z i d p e r t a b l e t i s c a l c u l a t e d by t h e following formula: (A s a m pl e) (mg s t a n d a r d ) (Av. t a b l e t w t . i n mg) ( A s t a n d a r d ) (mg (5) where 5 i s t h e d i l u t i o n f a c t o r . 6 .4 2
Tetrazolium S a l t Reaction The i s o c a r b o x a z i d c o n t e n t i n bl ood may be d eter min ed i n t h e r a n g e o f 0.5 pg/ml o f plasma by t h e f o l l o w i n g p r o c e d u r e . Add 1.5 m l o f pH 7 . 3 p h o s p h a t e b u f f e r t o 1 m l o f b l o o d and l e t s t a n d f o r 1 0 m i n u t e s . Add 4 ml o f b u t y l a c e t a t e : b u t a n o l ( 9 : l ) and 0 . 7 5 gm o f Na2S04: MgO powder (30: 1 ) . Shake f o r 30 m i nut es and t h e n c e n t r i f u g e u n t i l t h e phases s e p a r a t e . Pipet 3 m l o f t h e organic phase i n t o a t e s t t u b e , add 0 . 1 ml o f t h e t e t r a z o l i u m r e a g e n t ( 0 .1 2 5 % 3,3'-dianisole-bis-4,4'-(diphenyl) - t e t r a z o l i u m c h l o r i d e i n methanol) and 0.1 m l o f O.UL N KOH. Place i n a b a t h o f b o i l i n g w a t e r e x a c t l y one minute t h e n c o o l r a p i d l y by immersing i n c o l d w a t e r . The i s o c a r b o x a z i d h a s r e d u ced t h e t e t r a z o l i u m s a l t t o a b l u e formazan. Read t h e a bs o r b a n c e o f t h e s o l u t i o n a t 520 nm w i t h i n 30 m i n u t e s . A t t h e same t i m e r un t h e above p r o c e d u r e on a 1 ml bl ood b l a n k and a ' l m l b l o o d sample c o n t a i n i n g 5 ugm o f r e f e r e n c e s t a n d a r d i s o c a r b o x a z i d . C o r r e c t f o r t h e bl ank and use t h e r e f e r e n c e s t a n d a r d t o c a l c u l a t e an e x t i n c t i o n c o e f f i c i e n t which i s us ed t o c a l c u l a t e t h e unknowns (16,17), 6.5
P o t e n t i o m e t r i c Sodium N i t r i t e T i t r a t i o n The p o t e n t i o m e t r i c sodium n i t r i t e t i t r a t i o n as d e s c r i b e d i n t h e NF XI11 i s t h e method o f c h o i c e f o r t h e a n a l y s i s o f t h e i s o c a r b o x a z i d fiiie chemical ( 6 ) . A sample
312
ISOCARBOXAZI D
of about 700 mg is accurately weighed and dissolved in 20 m l of glacial acetic acid. Following dissolution 20 ml of I1C1 arid 40 nil o f water is added and the solution cooled to room temperature. Titrate potentiometrically with 0.1N NaN02 solution using a calomel-platinum electrode system. Each ml of 0.1N NaN02 is equivalent to 2 3 . 1 3 of isocarboxaz id.
313
B. C . RUDY AND B. 2. SENKOWSKI
7.
References
M. Hawrylyshyn, Hoffmann-La Roche Inc., Personal Communication. 2 . J. H. Johnson, Hoffmann-La Roche Inc., Personal Communication. 3. L. B. Bandong, Hoffmann-La Roche Inc., Personal Communication. 4 . J. Boatman, Hoffmann-La Roche Inc., Personal Communication. S . W. Benz, Hoffmann-La Roche Inc., Personal communication. 6 . National Formulary XIII, 378-379 ( 1 9 7 0 ) . 7 . S . Moros, Hoffmann-La Roche Inc., Personal Communication. 8 . E. MacMullan, Hoffmann-La Roche Inc., Personal Communication. 9. R. Hagel, Hoffmann-La Roche Inc., Personal Communication. 1 0 * E. Lau, Hoffmann-La Roche Inc., Unpublished Data. 11. T. Gardner and E. Wenis, Hoffmann-La Roche Inc., Unpublished Data. 1 2 . R. Colarusso, Hoffmann-La Roche Inc., Unpublished Data. 13. B. Koechlin, M. Schwartz and W. Oberhznsli, J . PharmacoZ. ExptZ. Therap. 138, 11 ( 1 9 6 2 ) . 1 4 . M. Schwartz, Proc. Soc. Exp. G l . Med. 107, 613 1.
15. 16.
17.
(1961). F . Scheidl, Hoffmann-La Roche, Personal Communica-
tion, M. Roth and J. Rieder, Biochem. Pham. 1 2 , 445 (1963). B . Koechlin, L. D'Arconte, F. Rubio and R. Engleberg, Hoffmann-La Roche Inc., Roche Product ManuaZ ( 1971) .
314
ISOPROPAMIDE
Rulph S. Suntoro, Rickurcl J. Wurrcn, Geruld D. Roberts. Edward White, V , utid Peter P. Begosh
315
RALPH S. SANTORO e t a /
CONTENTS
1.
2.
3. I+.
5. 6.
7.
Description 1.1 Name, Formula, Molecular Weight 1.2 Appearance, Color, Odor, Taste Physical Properties 2.1 Infrared Spectrum 2.2 Nuclear Magnetic Resonance Spectrum 2.3 Ultraviolet Spectrum 2.4 Mass Spectrum 2.5 Melting Range 2.6 Differential Thermal Analysis 2.7 Thermogravimetric Analysis 2.8 Solubility 2.9 Polarography Synthesis Stability Degradation Drug Metabolic Products Methods of Analysis 6.1 Isopropamide Chemical 6.11 Elemental Analysis 6.12 Titration of Iodide Functional Group 6.13 Non-Aqueous Titration 6.1 I+ S pectrophotometric Analy8 is 6.15 Chromatographic Analysis 6.2 Dosage Forms 6.21 Spectrophotometric Analysis 6.22 Spectrophotometric Analysis in Presence of Interferences 6.23 Colorimetric Analysis Notes and References
-
316
ISOPROPAMI DE
1.
Description 1.1
Name, Formula, Molecular Weight Isopropamide is (3-Carbamoyl-3,3-diphenylpropyl)diisopropylmethy1)amonium iodide. It is also known as Darbid; Priamid; Tyrimide; 2,2-diphenyl-4-diisopropylaminobutyrimide methiodide.
Mol. wt.:48O.443
C23H331N20
1.2
Appearance, Color, Odor, Taste A white to off-white (very pale yellow) crystalline or amorphous powder, odorless, with an extremely bitter taste. ~~
2.
Physical Properties
2.1
Infrared Spectrum Figure 1 is the infrared spectrum of isopropamide (SK+F standard SJB-4Q6-226A ) taken in a mineral oil dispersion from 4000 625 cm on a Perkin-Elmer Model 457. R. Warren assigns the following bands (cm to isopropamide:
-
-'
3530 and 3475; free NH 3300; bonded NH2 1665; amide C=O 1585 and 14%; aromatic C=C and NH2 770-710;aromatic CH out-of-plane deformation mono-substituted phenyls
317
MICRONS 2 5
3 0
.O
so
6 0
T O
8 0
P O
10
I2
I4
I6
18 1 0
15 103540 0 0
w c m
WAVENUMBER I C M ~ l l
Figure 1.
-
Isnpropamide SK+F standard SJB-4406-22&, dispersion, Instrument: Perkin-Elmer 457.
mineral oil,
ISOPROPAMIDE
2.2
Nuclear Magnetic Resonance Spectrum I a i n e d in a deutero chloroform' solution of SK+F standard SJB-4406226-A which contained about 100mg/ml and tetramethyls i l a n e as internal reference on a JEOL ModelC 60 H.The following a S S i g n ~ ~ ~(Hz) ~ t € iwere made by R. Warren:
@
0 NH2
9
@
fJ@
- C - CI - CH2
By3 CH2 N D H ( C H J ) J ~
+ @
8
@
63 8 2 ; doublet, protons a t @
177; protons a t
@ @@
244.5 ; multiplet, protons a t @ 340 and 387; protons a t @ 447; protons a t @
319
-1
-
60 M C : ~ ~480 O
I
1
420
I
360 I
300
1
240
I
180
I
120
60
0 CPS
I
I
W
F3 C
I
9
I
8
I
7
I
6
I
5
I
4
I
3
I
2
I
1
0 PP m
Figure 2.
NMR Spectrum Isopropamide, SK+F standard SJB-4406-226A in deuterochloroform tetramethylsilane internal reference, Instrument: JEOL C 60 H .
ISOPROPAMI DE
2.3 Ultraviolet Spectra The ultraviolet absorption spectrum of isopropamide (SK+F standard SJB-4406-226A ) in water is shown in Figure 3. Maxima at 265 nm (a = 0.745; € = 357.9) and 258.5 nm (a = 1.053; (= 505.9) are bands characteristic for the mono-substituted phenyl moiety (1). Figure 4 is the ultraviolet spectrum in water under conditions suitable for observing the iodide maximum absorbance at 222.5 nm (a = 37.0;E = 17,757) (2, 3 , 4 ). Beginning at 220 nm the automatic slit begins to rapidly open. Neither maximum wavelengths nor absorptivities different from N those determined in water solution were observed in C.1 hydrochloric acid and 0.1 N sodium hydroxide solutions. Figure 5 is the ultraviolet absorption spectrum of isopropamide in methylene chloride. The maximum at 245 nm (a = 33.7; f = 16,204) is due to the iodide. The automatic slit begins to rapidly open below 227.5 nm. Figure 6 is the ultraviolet absorption curve of isopropamide in water after the solution was passed through an anionic exchange resin (5) in which the iodide was converted to the chloride; this allows the monosubstituted phenyl spectrum to be more readily observed. Maxima appear at 265 nm (a = 0.721 ; f = 346.4), 258.5 nm = 411.5) (a = 0 . 9 k ; C = 451.8), and 252.5 nm (a = 0.856; Neither maximum shifts nor absorptivity differences were observed in the above spectrum when the solution pH was rendered either acidic or basic.
321
RALPH S.SANTORO e t a / .
Fig. 3
322
ISOPAOPAMIDE
Fig. 4
323
R A L P H S . SANTORO e r a /
WB-44C6-226A
Concentmtmn:
0.0338 n d m l blethylcne Chloride
cell I’ath:
1 Cm
Fig. 5
324
ISOPROPAMIDE
Fig. 6
325
RALPH
S. SANTORO era/.
2.4 Mass Spectrum The mass spectrum of SK+F 4740-5 (SK+F standard SJB-’t’t06-226-A) was obtained by direct insertion of the solid into an Hitachi Perkin-Elmer RMU-6E low resolution mass spectrometer. The results are presented in tabular form in Table I and as a bar graph in Figure 7. E. White and G. Roberts provided the following observations and assignments : The compound thermally decomposes in the instrument, and consequently no molecular ion is observed for the quaternary salt. The spectrum consists of the sum of the spectra of six thermal products which are listed in Table 11. All of the structurally significant peaks are discussed below. Compounds I, 11, and 111, tertiary amines show a molecular ion as noted in Table 11. Each of the compounds cleaves p to the amino nitrogen by losing a methyl group resulting in peaks at m/e 100, rnfe 295 and mfe 323 respectively. Compounds I1 and 111 also exhibit cleavage p to the amino nitrogen with strong peaks at rnfe 86 and mle 114 respectively. Following the loss of the methyl groups from the molecular ions of I1 and I11 there is l o s s of NH, CHO resulting in peaks at mfe 250 and m/e 278. Following the loss of the methyl group from I there is loss of propene resulting in a peak at rnfe 58 as transition is supported by a metastable at rnfe 33.6 Compounds IV, V, and VI are alkyl iodides and as noted in Table 2 a molecular ion is observed for IV and V. Although no molecular ion is observed for VI, its presence is indicated by fragment ions. The peaks at m/e 238 and mle 237 represent the loss of an iodine atom and hydrogen iodide. The ion at m / e 237 further decomposes t o m/e 236 by loss of its hydrogen atom, this transition being supported by a metastable at m/e 235.0. The probable origins of mle 193 and m/e 194 are the l o s s of NH2CH0 from mle 238 and the loss of NHCO from m/e 237. The ions at mle 178 and m/e 179 are possibly formed by loss of a methyl group from mle 193 and mle 194. Other structurally significant peaks which could have originated from more than one of the six compounds
326
ISOPROPAMIDE
MIS 15.8 16.9 19.0
P9.0
8i.a P7.R 8R.R R9.0
3m.m 31.0 3e.m
INTCN. 0 .s
MASS 79.8
INTEN.
a.p
8m.R “ 1 .G
A.5
R.5
R.S
42.6
4.7
e.9 B3.5
83.8 u4.0 R5.R 46.R
s.n 3.
s
11.7 8.9 m.4
97.G R8.R R9.m
33.c
@.a
90.A
34.a
I .9
36.1
R.9
37.R 35.0
9.n 3.4
91.n 3P.n 91.n 94.m
39.63
~m.4
y5.m
4e.e
7. A 49.7
q6.a
41.0 a8.m
43.R
94.5 5R.R
3.7 5.6
1ma.R
I
l0S.Q
1~3.m
0.4
I55.P
R.7
I .5 I .4 P. I
14n.0 159.~ 1nm.R 16i.a
R.5
I
55.0
0.4 m.4
56.0
PI .4
11e.n
e.4 a.4
63.8
3.7 8.7 3.4 0.5 1.1 (1.9
64.69
6S.8 67.8 68 .a 69.R
70.8
6.3
71.9 7Q.8 73.8 z4.9 7S.8
5.9 16.8 1.5 0.9
76.8
4.8 18.8
71.9
m.9
e. I 8.8
l26.R i27.m lPR.8 l29.Q 138.8 131.8 132.0 133.0
i6n.R
I 6’1.13 164-R 17a.e 171.m 1’)P.R 174.0 f7S.P I 7n.e
.5
Q.6
I 1P.m 113.0 114.8 I IS.# I i6.m ll7.R I i8.m I 19.m 180.0 l2l.R 105.e
I ns.a
13.9 4.1
IF7.R I09.R
0.5 1.6
1LP.R
1.7
1w.a
4.3
a.4 R.5
9.3 6.4
I .4 7. I
Il1.R
a.3
4,s
V.6
0.9 1Qfl.R
4. I 1.3 1.9 12.5
151.R
in?.#
(1.-
m.a
15i.m I -4.R
i610.m
R.4 1.1
0.4
14P.P
9.B 1 .R 14.9 t .n
9.a
ICI1.A I149.W
INTCW.
1.1 P.2
89.9 7.n 3.?
$1.8 S2.R s3.0
S7.0 58.8 59.0 68.0 68.0
149.R 15R.R
P.!?
1nn.a
46.8 5A.B
54.R
14P.8 I43.P I4h.R
9.7 77.5 5.3
R.4
45.R
.Y
m.9
97.0 9q.m 99.0
P9.b 15.Q
04.8
MASS 137.0 I3R.R 139.0 14R.R I4I.R
1.9
R.5 2.3 R.6 8.0 4.7 5.5 49.7 13.2 7.6 I .4 86.3 (1.9
(1.3 8.5 (1.4
IR0.8
P5. I 17.3 3.7
i6i.a 1RP.R
8.0
IS5.8
8.3
8.5 I. 3
lR7.0 IBR.0 189.0 190.0 191 .0 192.8 193.8 194.8 195.8 196.0
0.4 0.6
8.4
0.4
I .4 0.4
321
3.0 4.4
7.5 2R-6 81.6
33.3 4.2 8.4
I .a 2. 1 6.8
fl.8 0.4 1.1 0.6
8.3 8.9
0.3 8.4 0.4 3.Q 86.0
35.1 36.4 6.5
a.
7
6.8 e.3 8.7
9.3
895.8 e96.0 297.0 305.8 309.0 310.0 311.0 323.0 384.8
(14.8
31 -9 11.7
8.8 0.9 1.6
8.3 3.3
280.8 292.8
33.8
0.9 0.4
1353.9 R64.0
2.3
4.1
lt9.R 179.0
1.5 18.9 18.1 1.8 I .m
835.9 936.8 Q37.8 238.8 P39.0 848.0 850.0 851.8 250.8
3. I 0.8
P-6
1w.a
1113.0
$23.8 815.8 R34.8
265.0 261.8 868.8 876.8 e77.0 278.8 879.8
31.5
R.5 1.4
203. 8 Q84.8 Q8S.0 286.8 ea7.0 209.0 209.0 Ql0.0 QlLa 0 Ql2.0 R1R.A PI9.G BP(1.a eei.0 Qe2*0
1r 4 0.8 1.2
8.3 4.8
1.7 8.4
8.8 5.0
1.2
O.P 0.3
358.8
0.4 0.8 0.0 8.8 0.4 0.8
339.8
8.3
fn 9
z
20
-I
:: 0
i " ' I " ' I " '
50
Figure
90
130
I " ' I " '
170
210
I
I
I
I
I
250 290 330 370 410 450 490
7. Low resolution mass spectrum of isopropamide, SK+F standard SJB-4406-226A.
ISOPROPAMIDE
m / e 127 (I4), m / e 128 ( H I ? )
are m l e 43 [CH(CH,);?,
and m / e
,
TABLE ---
Thermal I
I1
CH,
I1
Products of I s o p r o p a m i d e
NLWCH~ )272 9?
M
+
115
M
+
310
y 3
NH2 C C CH2 CH2 N CH(CH3 I
)2
8
IV
CHj I
M
VI
M
0
329
+
+
142
n o t observed
RALPH S. SANTORO e t a /
2.5 -Melting Range
Isopropamide (SK+F standard SJB-4h6-226-A) 191.pC. without decomposition melted between 189.0 under USP conditions for class I substances (6).
-
2.6
Differential Thermal Analysis The differential thermal analysis of isopropamide (SK+F standard SJB-4406-226A ) beginning at 43O C and-with a heating rate of 20°C/min. resulted in a single major me1ting endotherm at 200' C
.
Other chemical lots tested under the same conditions showed minor endothermic transitions below the major endotherm. These minor transitions have been tentatively attributed to polymorphic forms known to exist with this compound (7).
2.7
Thermogravimetric Analysis A thermogravimetric analyeis performed on isopropamide (SK+F standard SJB-4406-2264) showed a 0.5' f 0 loss in weight complete at about 105'C. The measurement was performed under nitrogen sweep at a heating rate of Additional weight was rapidly lost as the 10'Clrnin. sample began melting 8t approximately 18pc.
330
ISOPROPAMIDE
2.8 -Solubility
The following solubilities were obtained at room temperature: Solvent ether benzene cyclohexane pH 7.5 buffer water 0.1 N hydrochloric acil 0.1 % sodium hydroxide acetzne 9 9 1 0 ethanol methylene chloride chloroform methanol
Solution -color1ess color1 ess colorless color1ess color 1ess faint yel-Jw color1ess bright yellow faint yellow brownish yellow deep brownish yellow deep brownish yellow
conc. mg / ml
0.07 0.09 0.10
20.7 21.2 23.6
23.6 24.9 109O .
330.4 >500
> 500
In addition, the following solubilities at room temperature have been reported ( 8 ): Solvent Ethyl acetate 1,1, dichloroethane isopropanol Methyl ethylketone 1 g hydrochloric acid
Conc. mdml 0.1 1*3 3.2
4.0 29.0
331
RALPH S. SANTORO et a/.
2.9
Polarography The polarogram was obtained on isopropamide (SK+F potassium nitrate with a standard SJB-kh06-28A ) in 0.1 standard calomel IdropDing mercury electrode system at a concentration of 5 x 10 -’& molar ( 9 ) . The E 112 was -0.25k V. The E 112 for iodide determined under similar conditions was
[email protected] V.
7.
Synthesis The synthetic pathway to isopropamide includes the following steps (Figure 8):
2-Diisopropylaminoethyl chloride (I) is condensed with diphenylacetonitrile (11) in the presence of an alkaline condensing agent and the product 4-diisopropylamino-2,2diphenvlbutyronitrile (111) purified by distillation. By reaction with acid, the 4-diisopropyLamino-2,2diphenylbutyronitrile (111) is partially hydrolyzed to 4diisopropylamino-2,2-diphenylbutyramide (IV) which is Durified by recrystallization. Finally (3-carbamoyl-3,3-diphenylpropyl)-diisopropylmethylammonium iodide (V) is prepared by reacting 4diiso~ronylamino-2,2-diphenylbutyramide(IV) in solution with methyl iodide. The product is collected by filtration, washed, dried and assayed. IsoproDamide is covered by U . S . Patent Number 2823233. The original synthesis is described by Janssen et al. (lo). l~
-Stability - _----
Degradation
_I_--_I
The dry chemical stored in glass bottles at room
temnerature is stable for at least ? years. In aqueous eolution (1 - 5 rngtrnl) stored at room temperature the drug is stable for at least 6 months 01). Because the drug is stable, degradation products have not been observed to occur either under normal or exaggerated storage conditions.
5. g ~ u gMetabolic Products No isoDropamfde metabolic products have been reported thus far.
332
Figur.:
.!
-
SYNTHETIC PATHWAY TO ISOPROPAMIDE
NC -kH
+
C1CH2CHPi
alkaline
\HC,
/CH,
condensing agent
>
1
RALPH S.SANTORO e t a / .
6. Methods of Analysis 6.1
Isopropamide Chemical 6.11
Elemental Analysis
Element C
H N 6.12
Theory
O l a
Range Obtained
57.50 6.90
57.80
5.83
5.69
7.00
- 57.92 - 7.06 - 5.78
-Titration .
of Iodide Functional Group An accurately weighed sample (About 1 g.) is dissolved in a 5:5: 1 mixture of water:methyl alcohol: silver nitrate glacial acetic acid and titrated with 0.1 and Eosin Y as indicator until the precipitate becomes rose red. Each milliliter of 0.1 N silver nitrate is equal to 0.01269 of iodide or 0.04804 g. of isopropamide.
6.13 -_. Non Aqueous . _-.-- Titration ---- ~
~
An accurately weighed sample (about 0.75 g.) is dissolved in glacial acetic acid, mercuric acetate and methyl violet indicator added, and titrated with 0.1 N Derchloric acid in acetic acid to a blue endpoint. Ezch milliliter of 0.1 N perchloric acid is equivalent to 0.0'+804 R. of isopropamide.
6.14
-Spectrophotometric __ Analysis _~
The ultraviolet absorption spectrum obtained either by direct dilution or preliminary treatment with resin (see section 2.3) may be used for determining purity.
6.15 Chromatographic Analysis The following thin layer method may be used for the qualitative purity evaluation of isopropamide: Equilibrate a mixture of 60 ml. each of isoamyl and tert-amyl alcohols with 20 ml. of 88'1, formic acid dissolved in 100 ml. of water. Discard the aqueous layer and use the alcohol layer as the chromatographic solvent. Spot 25 and 50 micrograms of isopropamide dissolved in methanol two cm. from the edge of an 'Avicelf 334
ISOPROPAMIDE
or cellulose plate (12)~place the prepared plate in a suitable chromatographic chamber lined with filter paper saturated with the developing solvent, and allow to equilibrate for 45 minutes. Allow the solvent to rise to a line drawn across the plate 10 cm. from the origin, remove the plate, and air dry in a fume hood until solvent vapore are no longer detectable. The developed chromatogram may be visibilized under ultraviolet light (254 and 365 nm), visible light, and iodoplatinate reagent (13). The quaternary moiety has an approximate Rf of 0.8, while the iodide appears at approximately 0.2.
6.2 Dosage Forms Isopropamide is found in dosage forms both alone and in combination with primary and tertiary amines. Assay methods include ultraviolet analysis after extraction of interfering amines and treatment with an anionic exchange resin, and colorimetric analysis by ion-paring with acid dyes and extraction of the complex into an organic solvent.
S pectrophotm e t r i c Ana 1ys is The ultraviolet assay of tablets which contain only isopropamide as the active ingredient is the most direct method employed (14). Twenty tablets ( 5 mg/ tablet) are placed in a 250 ml. volumetric flask, disintegrated in about 150 ml. of water, and diluted to volume with water. The solution is filtered through Whatman No. 1 filter paper (15),W.O ml. of the filtrate percolated through an anion exchange column (16), and the column rinsed thoroughly with water. A l l eluates are collected in a 100 ml. volumetric flask and diluted to volume with water. The ultraviolet absorption spectrum of this solution is compared with that of a known standard of isopropamide under the same spectrophotometric conditi ns and the assay value per tablet calculated. 6.21
6.22 spectrophotometric Analysis in Presence of Interferences The ultraviolet assay of dosage forms which contain nther amines removable by solvent extraction is accompl shed by treating the eluate collected in 6.21 with ammonium hydroxide until basic and extracting with ether to remwe the Interfering amines (17). 1
335
RALPH S. SANTORO e t a / .
6.23
Colorimetric Analysis The s e l e c t i v e d e t e r m i n a t i o n of isopropamide . . by i o n - p a i r i n g w i t h methyl orange dye h a s been d e s c r i b e d (18). The q u a t e r n a r y amine i s i o n - p a i r e d a t pH 10.2 and e x t r a c t e d i n t o chloroform. Primary, secondary, and t e r t i a r y amines t e s t e d through t h e procedure d i d n o t cqmplex o r i n t e r f e r e w i t h t h e subsequent s p e c t r o p h o t o m e t r i c d e t e r m i n a t i o n a t 520 nm.
336
ISOPROPAMI DE
7. Notes and References XVIII, p. 825. Brode, W.R., Chemical Spectroscopy, 2nd Ed., John Wiley and Sons Inc., New York, (1947). 3. Brode, W.R., J. Am. Chem. SOC., 48, 1877, (1926). 4. Bolz, D.F., Colorimetric Determination of Nonmetals, Volume V I I I , Interscience Publishers Inc., 1947, p. 218. 5 . Amberlite IRA !+GO, chloride form, Mallinkrodt Chemical Works. 6. U . S . P . XVIII, p. 935. 7. I. B. Eisdorfer, Personal Communication. 8. Paul Janssen, Private Communication, Eupharma-NedChem Pharmaceutical Laboratories. 9. Kolthoff, I.M., and Lingane, J . J . , Polarography, Second Edition, Interscience Publishers, New York and London, 1952, p. 579. 10. Janssen et al., Arch. Intern Pharmacodyn., 103, 1955, 82. 11. Private Communication, Eupharma-Nedchem Pharmaceutical Laboratories. 12. 'Avicel'-microcrystalline cellulose American Viscose. Silica gel may cause decomposition of the compound and is to be avoided. 13. One gram of chloroplatinic acid, 10 ml. of 1; hydrochloric acid, and 5 g. of potassium iodide diluted to 250 ml. with waterasa stock solution. Refrigerate. Prepare a working solution with equal volumes of stock solution and water made 112" l o with 88" lo formic acid. 14. M. Kushner, Personal Communication. If the solution is not clear at this point it will 15 be necessary to add 5 ml. of l@ /o aluminum chloride and 2 ml. of concentrated ammonium hydroxide to the l5G ml. of water before diluting to volume. 16. Amberlite IRA LOO, chloride form. 17. P. DeLuca and W. F. Witmer, Personal Communication. 18. R. Santoro, J. Am. Pharm. ASSOC., S c i . Ed., 49, 1960, 666.
1.
U.S.P.
2.
-
-
337
RALPH S. SANTORO e t a / .
Acknowledgements The authors wish to thank Joan Rudin for her search of the literature and Patricia Brittingham for her invaluable secretarial help.
338
LEVALLORPHAN TARTRATE
Bruce C. Rudy and Berriurd Z. Senkowski
339
B. C RUDY AND B 2 . SENKOWSKI
INDEX Analytical P r o f i l e - Levallorphan T a r t r a t e 1.
Description 1.1 N a m e , F o r m u l a , M o l e c u l a r Weight 1.2 A p p e a r a n c e , C o l o r , Odor
2.
Physical Properties 2.1 I n f r a r e d Spectrum 2.2 Nuclear Magnetic Resonance Spectrum 2.3 U l t r a v i o l e t Spectrum 2.4 F l u o r e s c e n c e S p e c t r u m 2.5 Mass S p e c t r u m 2.6 Optical Rotation 2.7 M e l t i n g Range 2.8 D i f f e r e n t i a l Scanning Cdlorimetry 2.9 Thermal G r a v i m e t r i c A n a l y s i s 2.10 S o l u b i l i t y 2 . 1 1 X-ray C r y s t a l P r o p e r t i e s 2.12 D i s s o c i a t i o n C o n s t a n t
3.
Synthesis
4.
S t a b i l i t y Degradation
5.
Drug M e t a b o l i c P r o d u c t s
6.
Methods o f A n a l y s i s 6.1 Elemental Analysis 6.2 Phase S o l u b i l i t y Analysis 6.3 Thin Layer Chromatographic A n a l y s i s 6.4 Gas L i q u i d Chroma t o g r a p h i c A n a l y s i s 6.5 Direct S p e c t r o p h o t o m e t r i c A n a l y s i s 6.6 Colorimetric Analysis 6.7 Nephelometric Analysis 6.8 T i t r i m e t r i c Analysis
7.
References
340
LEVALLORPHAN TARTRATE
1.
Description
Name, Formula, M o l e c u l a r Weight L e v a l l o r p h a n t a r t r a t e i s (-)-17-allylmorphinan-301 t a r t r a t e (1:l). 1.1
qy
I7 CH*CH=CH,
I
HO
H2C4H406
6
C
H NO.C4H6O6 1 9 25
M o l e c u l a r Weight:
433.51
1.2
Appearance, C o l o r , Odor Levallorphan t a r t r a t e occurs as a w h i t e o r pract i c a l l y w h i t e , o d o r l e s s , c r y s t a l l i n e powder. 2.
Physical Properties
2.1
I n f r a r e d Spectrum ( I R ) The I R s p e c t r u m of l e v a l l o r p h a n t a r t r a t e i s g r e a t l y c o m p l i c a t e d by t h e p r e s e n c e o f t h e t a r t a r i c a c i d . To o b t a i n t h e I R s p e c t r u m c h a r a c t e r i s t i c of t h e a c t i v e s p e c i e s , t h e f r e e l e v a l l o r p h a n b a s e was e x t r a c t e d from a b a s i c s o l u t i o n , d r i e d , and measured a s a K B r d i s p e r s i o n ( 1 . 7 mg l e v a l l o r p h a n / 3 0 0 mg KBr) on a P e r k i n E l m e r 621 S p e c t r o p h o t o m e t e r . T h i s s p e c t r u m i s shown i n F i g u r e 1 and t h e a s s i g n m e n t s f o r t h e c h a r a c t e r i s t i c bands a r e g i v e n i n T a b l e I (1). Table I I n f r a r e d Assignments f o r L e v a l l o r p h a n Frequency (cm-1)
C h a r a c t e r i s t i c of
3580*
OH s t r e t c h
3076
Aromatic CH s t r e t c h Asymmetric and symmetric s t r e t c h of CH2 C=C s t r e t c h of v i n y l g r o u p
2924-2919 and 2851 1644
*Detectable only i n s o l u t i o n spectrum, not i n KBr p e l l e t .
341
Figure 1
Infrared Spectrum of Levallorphan
WAVELENGTH
2.5 10
3
I
4 I
I
5 I
6 1
MICRONS
7 I
8 I
9 10 l
l
12 1 I
15 1822 3550 I l l 1 m
0
n C
[7
-
5.0 x l o 2 1 . 7 x 10 >5.0 x l o 2 7.6 x 1 0
2.11
X-ray C r y s t a l P r o p e r t i e s The x-ray powder d i f f r a c t i o n p a t t e r n of methyp r y l o n is p r e s e n t e d i n T a b l e I11 ( 9 ) . The i n s t r u m e n t a l c o n d i t i o n s a r e g i v e n below. Instrument Conditions : G e n e r a l E l e c t r i c Model XRD-6 S p e c t r o g o n i o m e t e r Generator: Tube t a r g e t : Radiation:
Goniometer: Detector:
50 KV-12-112 MA Copper Cu & = 1.542 8 O . l o Detector s l i t M.R. S o l l e r s l i t 3O Beam s l i t 0.0007 i n c h N i f i l t e r 4 O take off angle Scan a t 0.2' 29 p e r m i n u t e Amplifier g ain - 16 co u r s e, 8.7 f i n e Sealed proportional counter t u b e and DC v o l t a g e a t plateau
3 74
M E T HY P RY L O N
Pulse height selection EL - 5 volts; EU - out Rate meter T.C.4 2000 CIS full scale Chart speed - 1 inch per 5 minutes
Recorder:
Samples prepared by grinding at room temperature. Table I11 X-ray Powder Diffraction Pattern of Methyprylon 2e -
d (2)
10.00 13.78 14.64 15.62 16.29 18.90 19.54 20.24 20.72 21.96 22.00 24.00 24.55 25.32 26.14 26.88 27.36 27.86 28.68 28.78 28.90 29.51 30.42 31.60 33.14 34.32
8.85 6.43 6.05 5.67 5.44 4.70 4.54 4.39 4.29 4.05 4.04 3.71 3.63 3.52 3.41 3.32 3.26 3.20 3.11 3.10 3.09 3.03 2.94 2.83 2.70 2.61
*d
-
**IlI0
*
**
III 0
28 -
-
13 100 53 7 50 7 3 28 6 11 11 12 4 29 17 23 2 14 3 3 3 12 18 4 6 4
35.02 35.36 35.77 36.22 38.18 38.88 39.10 40.10 40.49 40.82 41.98 42.32 42.72 43.02 43.12 44.06 44.52 44.66 44.80 45.18 46.70 48.34 48.58 50.00 50.30
d(&* 2.56 2.54 2.51 2.48 2.36 2.32 2.31 2.25 2.23 2.21 2.15 2.14 2.12 2.10 2.10 2.06 2.04 2.03 2.02 2.00 1.95 1.88 1.87 1.82 1.81
III
-0-
** 8 3 4 1 3 1 1 8 6 4 2 2 2 1 2 2 2 2 2 2 1 2 1 1 2
nh (interplanar distance) = relative intensity 2 Sin 8 (based on highest intensity of 1.00) 315
B. C. R U D Y A N D 5 . 2. SENKOWSKI
2.12 Dissociation Constant The pKa for methyprylon has been determined spectrophotometrically to be approximately 12.0 (10). 3.
Synthesis Methyprylon is prepared by the reaction scheme shown in Figure 7. 3,3-Diethyl-1,2,3,4-tetrahydro-2,4-pyridinedione, Presidon, i s reacted with formaldehyde yielding 3,3-diethyl5-hydroxymethyl-1,2,3,4-tetrahydro-2,4-pyridinedione (HMP) which is then hydrogenated using a Raney nickel catalyst to methyprylon (11).
4. Stability Degradation When methyprylon i s refluxed i n acidic, neutral, or basic aqueous solutions i n the presence of oxygen, it break down into several carboxylic acids; e.g. formic acid, acetic acid, propionic acid, and diethyl acetic acid. Traces of unidentified amines and ketones are a l s o observed (12). When pure methyprylon is stored in well-closed, light resistant containers, the substance is quite stable. 5. Drug Metabolic Products The major metabolic pathways of methyprylon i n dogs and Methyprylon as the humans is shown in Figure 8 (13-18). intact drug as well as its 5,6-dehydrogenated metabolite are found in blood (13,14), I n addition to the 5,6-dehydrogenated metabolite, several other metabolites due to oxidation are found in urine. These include the 6-oxymetabolite from the direct oxidation of methyprylon and the oxidation of the methyl group to the alcohol and then to the acid i n the 5,6-dehydrogenated metabolite (16,18). 6. Methods of Analysis 6.1
Elemental Analysis The results from the elemental analysis are listed i n Table IV (19). Table IV Elemental Analysis of Methyprylon % Found Element Theory C 65.54 65.40 H 9.35 9.46 N 7.64 7.62 316
Figure 7 S y n t h e s i s of Methyprylon
26
- 2:o 0
+
0
H-C-H N
II
CH20H
0
04
I H
I
H PR E SlDON
FORMALDEHYDE
HMP
I
H2 Raney
I cC2H5 2H5&$ O
Nickel
H N I H
H
METHYPRYLON
Figure 8 M e t a b o l i c P r o d u c t s o f Methyprylon
m 0 7J
C 0
-I
0
cn
-
?25W
I-
3 J
-
0
"
-.
- -
-
n
-"
-
I\
c
F
0 I]
0
C 0
D
PHASE
. . 15-
SOLUBILITY
ANALYSIS
-
w
< b
z 0
oc
SAMPLE : METHYPRYLON
c
Fo
-
SOLVENT : HEPTANE SLOPE : 0.39% EQUILIBRATION : 72 HOURS at 2 5 OC EXTRAPOLATED SOLUBILITY : 19.65 m g 4 of HEPTANE
I 0
25
50
I
75
-
100
?J
METHYPRY LON
Temperature OC Injection Port: Column : Detector: Flow Rate: Quantities Injected:
210
180 2 50 40 c c l m i n u t e o f N i t r o g e n 10-100 pg of m e t h y p r y l o n i n 95% e t h a n o l 11 m i n u t e s
Retention Times :
6.5
Direct Spectrophotometric Analysis D i r e c t s p e c t r o p h o t o m e t r i c a n a l y s i s i s r a r e l y used b e c a u s e of t h e v e r y l o w molar a b s o r p t i v i t y of methyprylon. However, i n t h e a b s e n c e of any i n t e r f e r i n g s p e c i e s , t h e maximum a t 294 nm ( i n 2-propanol) c o u l d b e used f o r d i r e c t spectrophotometric analysis.
6.6
Colorimetric Analysis Methyprylon u n d e r g o e s e n o l i z a t i o n i n t h e p r e s e n c e o f a l k a l i t h u s p e r m i t t i n g t h e u s e of t h e F o l i n C i o c a l t e u r e a g e n t t o form t h e b l u e c o l o r e d complex ( 2 3 ) . T h i s method i s u t i l i z e d f o r t h e d e t e r m i n a t i o n of methyprylon p r e s e n t i n b l o o d o r plasma. After appropriate extraction o r other s e p a r a t i o n , t h e F o l i n C i o c a l t e u r e a g e n t i s added t o a b a s i c s o l u t i o n of t h e m e t h y p r y l o n and t h e a b s o r b a n c e of t h e b l u e complex i s measured a t t h e maximum a b o u t 700 nm ( 1 4 ) . The s e n s i t i v i t y l i m i t i s a b o u t 5 iJg/ml of b l o o d o r p l a s m a .
6.7
T i t r i m e t r i c Analysis The p o t e n t i o m e t r i c t i t r a t i o n of a b a s i c , aqueous s o l u t i o n of m e t h y p r y l o n w i t h 0.1N p o t a s s i u m f e r r i c y a n i d e i s t h e method of c h o i c e f o r t h e a n a l y s i s of m e t h y p r y l o n i n t h e b u l k form as w e l l as i n c a p s u l e s and t a b l e t s ( 2 4 ) . The end p o i n t i s d e t e r m i n e d p o t e n t i o m e t r i c a l l y by t h e u s e o f a calomel-platinum e l e c t r o d e system. Each m l of 0.1N p o t a s sium f e r r i c y a n i d e i s e q u i v a l e n t t o 9 . 1 6 2 mg of m e t h y p r y l o n .
38 I
B. C . RUDY AND B. 2. SENKOWSKI
7. References 1. Hawrylyshyn, M., Hoffmann-La Roche Inc., Personal Communication. 2. Johnson, J. H., Hoffmann-La Roche Inc., Personal Communication. 3 . Rubia, L. B., Hoffmann-La Roche Inc., Personal Communication. 4. Boatman, J., Hoffmann-La Roche Inc., Personal Communication. 5. Benz, W., Hoffmann-La Roche Inc., Personal Communication. 6. National Formulary XIII, First Supplement, p 1020 (1970). 7 . Moros, S . , Hoffmann-La Roche Inc., Personal Communication. 8. MacMullan, E., Hoffmann-La Roche Inc. , Personal Communication. 9. Hagel, R. B., Hoffmann-La Roche Inc., Personal Communication. 10. Lau, E., Hoffmann-La Roche Inc., Unpublished Data. 11. Pecherer, B., Hoffmann-La Roche Inc., Unpublished Data. 12. Frick, H., Hoffmann-La Roche Inc., Unpublished Data 13. Pellmont, B., Studer, A . , and Jurgens, R., Schweiz. Med. Wschr. , 85, 350 (1955). 14. Randall, L. O., Iliev, V., and Brandman, O., Arch. I n t . Pharmacodynamie , 106,388 (1956). 15. Bernhard, K., Just, M., Lutz, A . H., and Vuilleumier, J. P. , HeZv,. Chim. A c t a , 40, 436 (1957). 16. Pribilla, O., Archiv. f;*rT o x i k o l o g i e , 1 8 , 1 (1959). 1 7 . Boesche, J . and Schmidt, G . , Arzneim. F G s c h . , 16, 548 (1966). 18. Boesche, J., Arzneim. Forsch. , 2 , 123 (1969). 19 * Scheidl, F., Hoffmann-La Roche Inc., Personal Communication. 20. Frahm, M., Gottesleben, A. , and Soehring, K. , Arzneim. Forsch. , 11,1008 (1961). 21. Beratti, N., Hoffmann-La Roche Inc., Unpublished Data. 22. Mahn, F., Hoffmann-La Roche Inc., Unpublished Data. 23. Folin, O., and Ciocalteu, V., J . B i o l . Chem., 73, 627 (1929). 24. National Formulary XIII, pp. 458-459 (1970).
.
382
PH ENELZINE SU LF ATE
Reviewed b y L. Chafetz
383
ROBERT E. O A L Y
CON TEN T S
Analytical Profile
1. 2.
3.
4. 5. 6.
7,
-
Phenelzine S u l f a t e
Description 1.1 N a m e , F o r m u l a , M o l e c u l a r W e i g h t 1 . 2 A p p e a r a n c e , C o l o r , Odor Ph y s i ca 1 P r o p e r t i es 2 . 1 I n f r a r e d Spectrum 2.2 N u c l e a r Maqnetic Resonance Sp ect ru m 2 . 3 Mass S p e c t r u m 2.4 Ultraviolet Spectrum 2.5 D i f f e r e n t i a l Thermal A n a l y s i s 2.6 Thermogravimetric Analysis 2.7 M e l t i n g Range 2.8 S o l u b i l i t y 2.9 X-Ray D i f f r a c t i o n Powder A n a l y s i s Synthesis Stability Metabolism Methods o f A n a l y s i s 6 . 1 Spectrophotometric Analysis 6.2 Polarography 6.3 T i t r i m e t r y 6.4 Chromatography 6 . 4 1 Gas C h r o m a t o g r a p h y 6.42 Thin Layer Chromatography 6.5 S p o t T e s t s References
384
PHENELZINE SULFATE
1.
DescriDtion
N a m e , Formula, M o l e c u l a r Weight Phenelzine S u l f a t e i s B-phenylethylI t i s a l s o known hydrazine dihydrogen s u l f a t e . as p h e n e t h y l h y d r a z i n e s u l f a t e . 1.1
A p p e a r a n c e , C o l o r , Odor White t o y e l l o w i s h w h i t e c r y s t a l l i n e powder h a v i n g a c h a r a c t e r i s t i c o d o r .
1.2
2.
Physical Properties 2.1
I n f r a r e d Spectrum The i n f r a r e d s p e c t r u m ( F i g u r e 1) of p h e n e l z i n e s u l f a t e was d e t e r m i n e d a s a K B r p e l l e t i n a P e r k i n - E l m e r model 6 2 1 s p e c t r o p h o t o m e t e r . The s p e c t r u m o b t a i n e d i s i d e n t i c a l t o t h a t o f p h e n e l z i n e s u l f a t e w h i c h a p p e a r s as S a d t l e r i n f r a r e d s p e c t r u m #24825. T h e broad band a t a b o u t 2500 c m . - ’ may b e a t t r i b u t e d t o t h e hydrazine s a l t . The b a n d s a t 758 c m . - ’ a n d 705 c m . - ’ may b e a t t r i b u t e d t o t h e m o n o s u b s t i t u t e d benzene moiety. N u c l e a r Magnetic Resonance Spectrum The NMR s p e c t r i i m o f p h e n e l z i n e s u l f a t e w a s d e t e r m i n e d i n a V a r i a n A-60 i n s t r u m e n t e m p l o y i n g DMSO a s t h e s c l v e n t ( F i g u r e 2 ) . The spectrum d i s p l a y e d s i n g l e t s a t 6 7.75 (hydrogen bonded t o n i t r o g e n ) and a t 6 7.2 (aromatic). O t h e r a b s o r p t i o n w a s c e n t e r e d around 6 3.0 ( m e t h y l e n e bonded t o m e t h y l e n e and N H ) and 6 2 . 5 (methylene bonded t o methylene and p h e n y l ) D e u t e r i u m e x c h a n g e ( F i g u r e 3 ) w a s p e r f o r m e d on t h e s a m p l e . The a b s o r p t i o n band a t 6 7 . 7 5 d i s a p p e a r e d v e r i f y i n g t h e a s s i g n m e n t o f t h i s band t o hydrogen bonded t o n i t r o g e n . 2.2
.
2.0 100
0 5000
2.5
3.0
4.0 5 . 0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
9.0
I
I
I
4000
3000
2000
1800
1700
1600
W A V E NUMBERS I N C Y
Figure 1
-
-'
1500
1400
1300
1200
I
-
11.0 12.0 13.0 14.0 15.0 I
-
I
.
-
1100
1000
.
.
.
.
I
1
1
1
1900
10.0 1
I
900
I n f r a r e d Spectrum o f P h e n e l z i n e S u l f a t e .
800
700 640
500
400
300
z 00
200
0 cpr
rn C
r
n b
--I
rn
I 8.0
I
I
7.0
I
1 6.0
I
1 5.0
I
1
4.0
I
I
3.0
I
I 2.0
I
I
1.0
F i g u r e 2 - NMR S p e c t r a of P h e n e l z i n e S u l f a t e
I
0 PPm
x
500
1
1
8.0
I
300
400
1
7.0
I
I
6.0
I
I 5.0
100
200
I
I
4.0
I
I
3.0
1
I 2.0
I
1 1.0
I
0 PPm
F i g u r e 3 - NMR S p e c t r a of P h e n e l z i n e S u l f a t e - D e u t e r i u m Exchange
PHENELZINE S UL F A T E
2.3
Mass S p e c t r u m A m a s s s p e c t r u m of p h e n e l z i n e s u l f a t e could not be obtained d e s p i t e s e v e r a l attempts. An A E I 902 w a s employed w i t h a n i o n i z i n g v o l t a g e of 7 0 ev and a t a t e m p e r a t u r e of 1 0 0 ° C . On r u n ning t h e material d i r e c t l y i n t h e probe, a spect r u m w h i c h showed l a r g e a m o u n t s of s u l f u r d i o x i d e resulted. Attempts a t running t h e f r e e base proved f r u i t l e s s a l s o . The sample w a s i n t r o d u c e d i n t o t h e mass s p e c t r o m e t e r t h r o u g h t h e h e a t e d i n l e t b u t t h e r m a l d e c o m p o s i t i o n o c c u r r e d and no spectrum w a s obtained. 2.4
U l t r a v i o l e t Spectrum R a j e s w a r a n a n d K i r k (I) r e p o r t e d h max ( E 1 8 6 2 ) of 258 nm. a n d X min o f 2 2 8 nm. i n 50% ethanol. Phenelzine s u l f a t e (0.0541% i n 50% e t h a n o l ) when s c a n n e d i n a C a r y 1 4 s p e c t r o p h o t o m e t e r b e t w e e n 350 and 2 2 0 nm. ( F i g u r e 4 ) , e x h i b i t e d t h r e e p e a k s a t 2 5 2 , 258 a n d 263 nm. w i t h A max a t 258 nm. ( a = 0 . 7 9 8 : F 1 8 6 9 ) . 2.5
D i f f e r e n t i a l Thermal Analysis A d i f f e r e n t i a l thermoqram h a s been
o b t a i n e d i n a Dupont m o d e l 9 0 0 DTA I n s t r u m e n t Two e n d o t h e r m s , o n e a t e m p l o y i n g a DSC c e l l . 134°C. ( c r y s t a l l i n e c h a n g e ) a n d t h e s e c o n d a t 1 7 2 ° C . ( m e l t i n g ) were o b s e r v e d ( F i g u r e 5 ) . H e a t i n g r a t e was 10' C . / m i n u t e . The d e t e r m i n a t i o n w a s c a r r i e d out i n a n i t r o g e n a t m o s p h e r e . A l t e r a t i o n i n t h e r a t e of h e a t i n g w o u l d t e n d t o s h i f t t h e endotherms. Thermogravimetric Analysis A thermogravimetric analysis was perf o r m e d ( F i g u r e 6 ) i n a D u p o n t m o d e l 9 5 0 TGA Instrument. The m e a s u r e m e n t was p e r f o r m e d u n d e r n i t r o g e n sweep a t a h e a t i n g r a t e o f 1 0 " C . / minute. N o w e i g h t loss w a s n o t e d u n t i l a b o u t 165" C . ( i n i t i a t i o n o f m e l t i n g ) . A f t e r t h i s p o i n t , w e i g h t w a s r a p i d l y lost. T h i s i n f o r m a t i o n t o g e t h e r w i t h t h e DTA i n d i c a t e s t h a t t h e 2.6
389
R O B E R T E. DALY
0. a
0. :
0.6
0.5
rn
*
c, Y
0.4
eq
e
0
2
0.3
pl
0.2
0.1
210
Figure 4
-
WAVELENGTH
320
W Spectrum o f Phenelzine S u l f a t e
390
0x3-
0aN3
PHENELZINE SULFATE
JV-
391
0 0
rn 0
2 3
0 '0
0
2 0
0
5 k
rn 0
m
8-4
e,
k
E
a:
c E crj k
N
a r
k -!
5
a:
q"
2 Y 0,
0
0 05
0 \o
0
w
0
rn
0
ROBERT E. D A L Y
392
a 0 v,
0 v,
w
0
*0
0
m
v)
0 0
m 0 v)
w
0
0
w
2
0
1
0 0
a v,
0
a,
c, m w
a, C
N
.d
C
a,
rl
a,
II)
c Y 4
h m
q" C
rl
a:
5 k
P
am:
s 2
PHENELZINE SULFATE
e n d o t h e r m a t 134O C . w a s d u e t o a n o n d e s t r u c t i v e a l t e r a t i o n i n t h e molecule (crystal change). 2.7
M e l t i n g Range The m e l t i n g r a n g e h a s b e e n r e p o r t e d ( 2 ) t o be 1 6 4 t o 1 6 8 " C . 2.8
Solubility Phenelzine s u l f a t e i s soluble i n water and p r a c t i c a l l y i n s o l u b l e i n e t h a n o l , c h l o r o f o r m and e t h e r . 2.9
X-Ray D i f f r a c t i o n Powder A n a l y s i s R a j e s w a r a n a n d K i r k (1) h a v e r e p o r t e d x-ray d i f f r a c t i o n data €or p h e n e l z i n e s u l f a t e . The powdered s a m p l e which h a d been a p p r o p r i a t e l y m o u n t e d on a r o t a r y s p e c i m e n h o l d e r , w a s s u b j e c t e d t o copper k-alpha r a d i a t i o n i n a Norelco G e i g e r C o u n t e r X-Ray S p e c t r o m e t e r . The d i f f r a c t i o n p a t t e r n s w e r e o b t a i n e d over a n a r c of 4 5 " . The i n s t r u m e n t w a s c a l i b r a t e d o v e r t h i s r a n g e , u s i n g powdered q u a r t z c r y s t a l s , a n d t h e " d " v a l u e s computed. Values are g i v e n i n T a b l e I . Table I
-
Ild" D i s t a n c e s U s i n g
C o p p e r K-Alpha Distances
3.
-
18.9, 3.24,
9.85, 2.79
&
Radiation
6.51, 5.42, 2.44
4.89,
3.90,
Synthesis
B i e l ( 3 ) h a s s y n t h e s i z e d p h e n e l z i n e by r e a c t i n g h y d r a z i n e h y d r a t e and p h e n e t h y l bromide under A y i e l d of 77% w a s o b t a i n e d . r e f l u x €or 7 h o u r s . Sacha and M a l a s n i c k i ( 4 ) condensed p h e n e t h y l c h l o r i d e w i t h hydrazine under r e f l u x i n anhydrous e t h a n o l i n a n i t r o g e n atmosphere €or 1 2 hours. T h e s o l u t i o n of t h e f r e e b a s e w h i c h w a s o b t a i n e d a f t e r removal o f h y d r a z i n e H C 1 b y f i l t r a t i o n was t r e a t e d w i t h s u l f u r i c a c i d i n anhydrous e t h a n o l
393
ROBERT E. DALY
.
(l.l/l W/W) A y i e l d of 2 1 % o f P - p h e n y l e t h y l hydrazine dihydrogen s u l f a t e w a s obtained. B i e l , e t . aZ. ( 5 ) h a s r e p o r t e d t h a t a r a l k y l a t i o n of hydrazine with primary a r a l k y l h a l i d e s a f f o r d s mono- ( a r a l k y l ) - h y d r a z i n e s i n y i e l d s of 6 0 t o 75% p r o v i d e d a t h r e e t o f i v e f o l d molar excess o f h y d r a z i n e h y d r a t e i s employed. Production of d i p h e n y l e t h y l h y d r a z i n e has been r e p o r t e d ( 6 ) as a by-product i n t h e r e a c t i o n .
0-
Reflux 7 hours
>\:2;::;:::;:
anhyd. EtOH
1
O H P - C H Z - N H - N H ~
H2S04 : E t O H
12R'/;d.
NP atm.
CH2-CH2C1 + NH~-NHP*H~O
4.
(l*l:l)
Sulfate
Stability
P h e n e l z i n e base i s e a s i l y o x i d i z e d . Decompos i t i o n o c c u r s when b a s i f i e d s o l u t i o n s a r e e x t r a c t e d , probably due t o autooxidation of t h e base. S c h l i t t , e t . aZ. ( 7 ) h a v e r e p o r t e d t h e a u t o o x i d a t i o n of p h e n e l z i n e s u l f a t e i n pH 5 . 9 p h o s p h a t e buffer. A u t o o x i d a t i o n i n pH 6 . 5 , 0 . 1 M s o d i u m c h l o r a t e a t 37' C. h a s a l s o b e e n r e p o r t e d ( 8 ) . D e c o m p o s i t i o n p r o d u c t s were n o t c h a r a c t e r i z e d . 5.
Metabolism D r a b n e r a n d Schwerd ( 9 ) i d e n t i f i e d u n c h a n g e d
394
PHENELZINE SULFATE
p h e n e l z i n e and p h e n y l a c e t y l g l u t a m i n e i n t h e u r i n e o f humans who h a d r e c e i v e d p h e n e l z i n e s u l f a t e . C l i n e s c h m i d t , e t . a l . ( 1 0 , 11) s t u d i e d t h e in v i t r o b i o t r a n s f o r m a t i o n a s w e l l as t h e in v i v o metabolism of C"-phenelzine i n rats. Phenylaceti c a c i d w a s i d e n t i f i e d as t h e m a j o r m e t a b o l i t e . F i s c h e r , e t . al. ( 1 2 ) h a v e d e s c r i b e d t h e e f f e c t o f p h e n e l z i n e on t h e e x c r e t i o n of 6phenethylamine. 6.
Methods of A n a l y s i s 6.1
Spectrophotometric Analysis
6 . 1 1 F e i g l (13) has r e p o r t e d t h e reduct i o n of l i t h i u m and s o d i u m molybdophosphotungs t a t e s o l u t i o n by h y d r a z i n e d e r i v a t i v e s . T h i s r e a c t i o n h a s b e e n a d a p t e d t o t h e d e t e r m i n a t i o n of p h e n e l z i n e s u l f a t e r a w m a t e r i a l o r t a b l e t s by Bose and V i j a y v a r g i y a (14). R e d u c t i o n i s c a r r i e d o u t i n a l k a l i n e s o l u t i o n with t h e production of a d e e p b l u e c o l o r w h i c h is m e a s u r e d a t 6 5 0 nm.
6.12 A c o l o r i m e t r i c method b a s e d on t h e formation of t h e hydrazone w i t h v a n i l l i n has been d e v i s e d ( 1 5 ) . The r e a c t i o n i s c a r r i e d o u t i n 0.5 N m e t h a n o l i c h y d r o c h l o r i c a c i d . Absorbance o f t h e y e l l o w s o l u t i o n i s r e a d a t 4 0 0 nm. S i n c e p h e n e l z i n e d e g r a d e s by o x i d a t i v e d e s t r u c t i o n of t h e h y d r a z i n e f u n c t i o n , t h i s method i s s t a b i l i t y indicating
.
Polarography The h a l f wave p o t e n t i a l versus s t a n d a r d calomel e l e c t r o d e ) of t h e a c e t o n e d e r i v a t i v e of p h e n e l z i n e w a s r e p o r t e d ( 7 ) as - 1 . 3 3 V i n pH 5 . 9 p h o s p h a t e b u f f e r ( 0 . 1 M KH~POI, : N a 2 H P O 4 * 2 H 2 O ) employing a 0 . 0 1 % g e l a t i n s o l u t i o n as a maximum s u p p r e s s o r . The d i f f u s i o n c u r r e n t c o n s t a n t ( I d ) w a s approximately 2.5. Four elect r o n s w e r e t r a n s f e r r e d f o r t h e r e d u c t i o n of t h e h y d r a z o n e d e r i v a t i v e . W a v e h e i g h t was p r o p o r t i o n a l t o c o n c e n t r a t i o n i n t h e r a n g e of 2 . 5 x lo-' t o 2.5 x M i n pH 5 . 9 p h o s p h a t e b u f f e r . 6.2
3Y.5
ROBERT E . D A L Y
6.3
Titrimetry P r o c e d u r e s b a s e d on t h e r e a c t i o n o f phenelzine s u l f a t e with iodine i n bicarbonate s o l u t i o n ( 2 ) and i n sodium h y d r o x i d e ( 1 6 ) and w i t h b r o m a t e and bromide i n a c i d s o l u t i o n ( 1 6 ) w i t h s u b s e q u e n t t i t r a t i o n of e x c e s s r e a g e n t ( i o d i n e o r bromide c o n v e r t e d t o i o d i n e ) i n a c i d s o l u t i o n w i t h t h i o s u l f a t e have been r e p o r t e d . B a s i c a l l y , t h e r e a c t i o n i n v o l v e d may be i l l u s t r a t e d a s follows:
Radecka and Nigam ( 1 7 ) have r e p o r t e d t h e d i r e c t t i t r a t i o n o f p h e n e l z i n e w i t h N-bromosuccinimide i n a c i d i c s o l u t i o n employing m e t h y l r e d a s t h e indicator. However, t h e i r r e s u l t s show a 5% p o s i t i v e b i a s . This b i a s is a t t r i b u t e d t o a l l y l i c b r o m i n a t i on by N -b r omosu c c i n i m i d e
.
6.4
Chromatography
Gas Chromatography C a r d i n i , e t . a l . (18, 1 9 ) and McMartin and S t r e e t ( 2 0 ) h a v e r e p o r t e d g a s chroma t o g r a p h i c methods which a r e r e p u t e d t o be quantitative. However, no q u a n t i t a t i v e d a t a a r e g i v e n . C o n d i t i o n s a r e r e p o r t e d i n T a b l e 11. 6.41
T h i n Layer Chromatography Q u a l i t a t i v e methods f o r t h e i d e n t i f i c a t i o n of p s y c h o t r o p i c a g e n t s have b e e n r e p o r t e d ( 2 1 , 2 2 , 2 3 , 2 4 , 2 5 ) . R f v a l u e s a r e summarized i n T a b l e 111. 6.42
6.5
Spot T e s t s A v a r i e t y of s p o t t e s t s have been re-
ported ( 2 6 ) .
T h e s e are summarized i n T a b l e 396
v.
T A B L E I1 - P a r a m e t e r s f o r G a s C h r o m a t o g r a p h y Ref. 18
19 w
c 4
20
Column g l a s s column 1 . 8 M x 2 mm.; 2 % GE-SE 3 0 on A e r o p a k 3 0 , 80100 m e s h
Column Temp.
Carrier Gas
program 70-250' a t 10.4O/
N2
Flow Rate
50 m l . / min.
Detector
FID
Detector Te m p
.
220'
C.
Injector Temp. 250'
C.
minute Q
I rn
Stainless steel 140' c o l u m n 1 . 2 M. x 2 mm.; 15%c a r b o w a x 20 M o n C h r o m o s o r b W alkalinized w i t h 5% KOH
C.
Stainless steel 140' c o l u m n 6' x 1/8" ; 2 % SE 3 0 + 0 . 1 % t r i s t e a r i n on s i l a n i z e d acid w a s h e d C h r o m o sorb W
C.
He
40 m l . / min.
FID
250'
C.
z
rn
P z
rn
m C
r
n
>
2 N2
3 0 ml./ min.
FID
ROBERT
TABLE I11
-
E. D A L Y
S u p p o r t , S o l v e n t System and Rf
V a l u e s f o r TLC of P h e n e l z i n e S u l f a t e Reference
Support
Solvent System
Rf
(X
21
silica gel G
chloroform: m e t hano 1 (8:2)
21
silica gel G
chloroform: acetone: d i e t h y lamine ( 5 : 4: 1)
88
21
silica gel G
cyclohexane: chloroform: d ie t h y l a m ine ( 4 :5 :1)
62
22
silica gel G impregnated with 0 . 1 M N aOH
hexane:benzene: diethylamine ( 7 5 : 1 5 : 10)
51
22
silica gel G impregnated with 0.1 M N aOH
methanol
72
22
silica gel G imp re gn a t ed with 0 . 1 M NaOH
acetone
75
22
silica gel G impregnated with 0 . 1 M NaHSO
methanol
41
398
100
100)
PHENELZINE SULFATE
TABLE I11 f c o n t . 1
R e f er e n ce
22
Support
Solvent System
Rf
( x 100)
silica gel G impregnated with 0 . 1 M NaHSO
95% ethanol
25
silica gel G activated a t 110" C. f o r 30 m i n u t e s
chloroform: m ethano1
37
23
silica gel G a c t i v a t e d as above
chloroform: methanol : 2 0 % ammonium hydroxide ( 2 : 1:l)
56
24
silica gel G activated at 100' C . f o r 1 hour
methanol:12 N ammon i um hydroxide (100: 1.5)
74
24
silica gel G impregnated with 0 . 1 N NaOH and activated a s above
cyclohexane: diethylamine: benzene (75: 20: 15)
44
24
s i l i c a g e l G acetone impregnated and a c t i v a t e d as above
65
24
s i l i c a g e l G chloroform: impregnated methanol and a c t i v a t e d ( 9 0 : 10) as above
75
+ ,
23
(1:l)
399
ROBERT E. DALY
TABLE I11 ( c o n t . )
Reference
Support
Solvent System
Rf
(X
100)
24
silica gel G
benzene: ethanol: 1 2 N ammonium hydroxide ( 9 5 : 15: 5 )
50
25
silica gel G imp re g n a t e d with 0 . 1 N KHSO 4
95% e t h a n o l
49
25
silica gel G impregnated w i t h 0.1N
cyclohexane: benzene : d i et h y lamine ( 7 5 : 15: 10)
52
methanol
72
acetone
75
N aOH
25
silica gel G imp r e g n a t e d with 0 . 1 N N aOH
25
silica gel G impregnated with 0.1 N N aOH
25
silica gel G imp r e g n a t e d with 0 . 1 N KHSO I,
methanol
62
25
silica gel G impregnated with 0 . 1 N NaOH
methyl acetate
53
400
PHENE LZI NE SULFATE
TABLE I11 ( c o n t . ) Reference 25
Support
Solvent System
chromedi a n-butanol: (Whatman #41) 5% c i t r i c impregnated acid w i t h 5% s o d i u m d i h y d r og e n citrate (some K2HP04 a d d e d t o prevent tailing)
Rf (x 100) 51
ROBERT E. DALY
TABLE I V
-
Reagents and Reactions
F o r TLC P r o c e d u r e s Reagent
Reaction
21
Folin-Ciocalteau's Reagent
blue violet with heating
21
5% phosphomolybdic a c i d i n e t h a n o l f o l l o w e d by exposure of t h e p l a t e t o ammonia v a p o r
blue
22
1%i o d i n e i n m e t h a n o l
brown
23
50 m l . o f 0 . 2 % ninhydrin i n methanol + 1 0 m l . of g l a c i a l a c e t i c a c i d + 2 m l . of
r o s e orange
Reference
2,4,6-trimethylpiperidine 23
1 0 % F e r r i c c h l o r i d e ; 1%
f l u o r e s c e i n : ammonia
fluorescent blue
23
S a t u r a t e d ammonium molybdate; s a t u r a t e d oxalic acid
celeste
24
Fo l i n - C i o c a l t e a u ' s Reagent
b l u i s h a t RT, b l u e when heated t o 100'
c.
24
Mandelin s R e a g e n t
pink a t RT, f l e s h a t 100' C. , f l u o r e s c e n t a f t e r heating
24
C i nn ama l d e h y d e R e a g e n t 5 m l . cinnamaldehyde + 95 m l . ethanol + 5 m l . conc. HC1
y e l l o w a t RT
402
PHENELZINE SULFATE
TABLE I V ( c o n t . )
Reference
Reagent
Reaction
24
0.25 g . p-dimethylaminobenzaldehyde + 5 g . of 85% p h o s p h o r i c a c i d + 20 m l . of water
lemon chromo after heating t o 1 0 0 ' C. f o r 1 0 min. and t h e n exposed t o ammonia v a p o r
24
Furf u r a l r e a g e n t s o l ' n A.) 1 m l . f u r f u r a l i n 99 m l . of acetone s o l ' n B . ) 4 m l . of c o n c . H 2 S 0 4 i n 96 m l . o f a c e t o n e
brown a t 1 0 0 '
25
C.
P l a t e examined u n d e r s h o r t w a v e W l i g h t and t h e n s p r a y e d w i t h t h e following sequence of r e a g e n t s : iodine
brown
Dragendorff ' s
orange
sodium n i t r i t e
d e e p brown
i odop l a t in a t e until a color develops
variously colored
403
ROBERT E. DALY
TABLE V
-
Spot Tests f o r Phenelzine S u l f a t e
Reagent
Response 0 . 5 mg.
2 0 1-14.
Froehde ' s Reagent
blue* It. b l u e
blue
Mandelin ' s R e a g e n t
green blue* brown
green faint orange
Marquis ' Reagent Mecke's R e a g e n t
r e d orange* grey
pink
R e i c k a r d ' s Reagent
It. blue
It. b l u e
F l u e c k i g e r ' s Reagent
brown
V i t a l i ' s Reagent
a. 1 b.)
Was i c k y ' s R e agen t
red o r a n g e
*
=
a f t e r warming
404
- -blue orange
---
--- --
PH E N E LZ IN E SULFATE
TABLE V I
- Composition o f Spot T e s t Reagents
Reagent
Composition
Froehde I s Reagent
0 . 5 % a q u e o u s ammonium m o 1y b d a t e
Mande l i n I s R e a g e n t
0 . 5 % a q u e o u s ammonium vanadate
Marquis
1 p a r t 37% formaldehyde i n 20 p a r t s concentrated
Reagent
sulfuric acid, freshly prepared before use Mecke ' s R e a g e n t
0 . 5 % aqueous s e l e n i o u s a c i d
(H2SeO 3 1 Reickard I s Reagent
1%a q u e o u s sodium t u n g s t a t e
F l u e c k i g e r ' s Reagent
0 . 5 % s o l u t i o n of t i t a n i u m d i o x i d e ( T i 0 2 1 i n concentrated sulfuric acid
V i t a l i s Reagent
a.) b.)
fuming n i t r i c a c i d 3% potassium hydroxide
i n ethanol Wasicky s R e a g e n t
1 0 % s o l u t i o n o f p-dimethylaminobenzaldehyde i n g l a c i a l acetic acid
305
ROBERT E. DALY
7.
References R a j e s w a r a n a n d P . L. K i r k , B u l l . N a r c o t i c s , U . N . , D e p t . S o : L 4 i l ~ f f ~ i 1r 4 s, No. I, 1 9 ( 1 9 6 2 ) .
1.
P.
2. 3. 4.
U.S.P. X V I I I . J . H . B i e l , US 3 , 0 0 0 , 9 0 3 , S e p t . 1 9 , 1 9 6 1 . A. S a c h a a n d L . M a l a s n i c k i , P o l 4 6 , 2 3 7 , O c t . 3 0 , 1 9 6 2 , C . A . 60, 4 5 4 f ( 1 9 6 3 ) . J . H . B i e l , A. E . D r u k k e r , T . H . M i t c h e l l , E . P . S p r e n g e l e r , P . A . N u h f e r , A. C . Conway and A. H o r i t a , J . A m . Chem. S o c . 8 2 , 2805 ( 1 9 5 9 ) . E . V o t o c e k a n d 0. L e m i n g e r , ColI. C z e c h . Chem. Commun. 4 , 2 7 1 ( 1 9 3 2 ) , C. A . 2 6 ,
5.
6. 7. 8. 9.
10.
11. 12. 13. 14.
15. 16. 17. 18. 19. 20.
5294 ( 1 9 3 2 ) . L . S c h l i t t , M. R i n k a n d M. von S t a c k e l b e r g , J , E Z e c t r o a n a l . Chem. 2 3 , 10 (1967). L . E . E b e r s o n a n d K . P e r s s o n , ,J. Med. Pharm. Chem. 5, 7 3 8 ( 1 9 6 2 ) . J . D r a b n e r a n d W . S c h w e r d , F r e s e n i u s ' Z. A n a l . Chem. 2 4 3 , 9 2 ( 1 9 6 8 ) . C. A . 70, 558941 ( 1 9 6 9 ) B . Van C l i n e s c h m i d t a n d A. H o r i t a , Biochem. Pharmacol. 1 8 , 1 0 1 1 (1969) Idem., i b i d . , 1021 (1969). E . F i s c h e r , B . H e l l e r , a n d A . H . Miro, A r z n e i m i t t e l - F o r s c h . 18, 1 4 8 6 ( 1 9 6 8 ) . F. F e i g l , "Spot T e s t i n O r g a n i c Analysis", E l s e v i e r Company, L o n d o n , 1 9 5 6 , p . 1 2 8 . B . C . Bose a n d R . V i j a y v a r g i y a , I n d i a n J . Pharm. 2 8 , 328 ( 1 9 6 6 ) . R. E . D a l y , u n p u b l i s h e d r e s u l t s M. M a r z a d r o a n d A. D e C a r o l i s , R e n d . I s t . S u n i t a 2 6 , 629 ( 1 9 6 3 ) . C . R a d e c k a a n d I . C. Nigam, Can. J . P h m m S c i . 2 , 17 (1966). C . C a r d i n i , V . Q u e r c i a a n d A . C a l o , :J. C h r o m a t o g . 37, 1 9 0 ( 1 9 6 8 ) . U. Q u e r c i a , C . C a r d i n i a n d A . Calo, i i ( ' l . C h i m . Farm. 1 0 7 , 3 8 3 ( 1 9 6 8 ) . C. M c M a r t i n a n d H . V . S t r e e t , J . Chromatog. 2 2 , 274 ( 1 9 6 6 ) .
.
.
406
PHENELZINE SULFATE
7.
References
21. 22. 23. 24. 25. 26.
(cont. )
E. S c h m i d , E. Hoppe, C . M e y t h a l e r a n d L. Z i c h a , A r z n e i m i t t e Z - F o r s c h , 1 3 , 9 6 9 (1963). W . W. F i k e , A n a l . Chem. 38, 1 6 9 7 ( 1 9 6 6 ) . A . A l e s s a n d r o , F. Mari a n d S . S e t t e c a s e , F arma co , Ed. Prat. 22, 437 ( 1 9 6 7 ) . I. Z i n g a l e s , J . C h r o m a t o g . 3 1 , 405 (1967). I. S u n s h i n e , W. W . F i k e a n d H . L a n d e s m a n , J . F o r e n s i c S c i . 1 1 , 428 ( 1 9 6 6 ) . P. R a j e s w a r a n a n d P . L . K i r k , B u l l . Narcotics, U.N., Dept. S o c i a l A f f a i r s 13, No. 3, 15 ( 1 9 6 1 ) .
407
This Page Intentionally Left Blank
PRIMIDONE
Raymond D. Daley
409
RAYMOND D. DALEY
CONTENTS
1. Description 1.1 Name, Formula, Molecular Weight 1.2 Appearance, Color, Odor, Taste 2.
Physical Properties 2.1 Infrared Spectra 2.2 Nuclear Magnetic Resonance Spectra 2.3 Ultraviolet Spectra 2.4 Mass Spectra 2.5 Crystal Properties 2.6 Melting Points 2.7 Solubility
3.
Synthesis
4.
Stability-Degradation
5.
Drug Metabolic Products
b.
Methods of Analysis 6.I Elemental Analysis 9.2 Chromatography 6.21 Gas Chromatography 6.22 Thin Layer Chronatography 6.23 Paper Chromatography 6.3 Absorptiometric Methods 6.31 Ultraviolet Absorption 6.32 Ultraviolet Determination as Phenobarbital 6.33 Colorimetric Methods 6.4 Polarography 6.5 Titration 6.6 Other Analytical Tests
7.
References
PRIMIDONE
1.
Description
1.1 Name, Formula, Molecular Weight Primidone i s 5-ethyldihydro-5-phenyl-k,6(lH, pyrimidinedione.
5H)-
H
‘‘b N
/
H
\ /
Mol. W t .
‘1.2~ 4 N 2‘2 1.2
218.26
Appearance, Color, Odor, Taste White, odorless powder, w i t h a s l i g h t l y b i t t e r
taste. 2.
Physical P r o p e r t i e s
2.1
I n f r a r e d Spectra
I n f r a r e d s p e c t r a 3f two c r y s t a l forms of primidone (here designated as Form I and Farm 11) a r e shown i n Figures 1 and 2. The samples were prepared as mineral o i l mulls between potassium bromide p l a t e s . A Beckman Model 111-12 instrument was used. Similar s p e c t r a a r e obtained with potassium bromide d i s p e r s i o n s (1,2), b u t t h e pressing operation usually causes d i s t o r t i o n s of t h e absorption bands. Some of the absorption bands may be assigned as follows: 3200 cm’ region, bonded N-!I s t r e t c h ; 1700 cm” region, amide C=O; 1600, &$lo, 760, 700, and 520 cm-’, aromatic ring. The absorption i n t h e 2900 cm’ region and p a r t of the absorption at &60 and 1380 cm’ i s due t o .ninera.l o i l .
a
>
20 z
A
0
L
N
P 0
P r m
a
?
a
u
a
?
a
0
3
'D
0
Hi-
m
K . W. BLESSEL, B. C. RUDY. A N D E. 2. S E N K O W S K I
i
560
T RI M E T HO B E NZ A M I DE HY DRO C H L OR ID E
Figure 6 DSC Curve for Trimethobenzamide Hydrochloride
I
1
I
I
A H f = I1 0 k c a l / m o l e
56 I
I
I
K. W. BLESSEL, B. C. RUDY,
A N D B. 2 . SENKOWSKI
The e x t r a p o l a t e d o n s e t of t e m p e r a t u r e program of 10°C/min. t h e m e l t i n g endotherm i s 185.8OC w i t h t h e peak a t 188.8OC. A l l t e m p e r a t u r e s are c o r r e c t e d . The AHf was c a l c u l a t e d t o b e 1 1 . 0 Kcal/mole f o r t h e m e l t i n g endotherm ( 7 ) . 2.9
Thermogravimetric A n a l y s i s (TGA) The TGA s c a n of trimethobenzamide h y d r o c h l o r i d e showed no s i g n i f i c a n t l o s s of w e i g h t up t o 23O0C a t a h e a t A c o n t i n u o u s l o s s o f w e i g h t w a s obi n g r a t e o f 10°C/min. s e r v e d between 230-5OO0C d u r i n g which range 80% of t h e sample weight was l o s t ( 7 ) . 2.10
Solubility The s o l u b i l i t y d a t a f o r a sample of r e f e r e n c e s t a n d a r d t r i n e t h o b e n z a m i d e h y d r o c h l o r i d e a t 25OC i s g i v e n i n Table I1 ( 8 ) . T a b l e I1 Solub il i t y (mg / m l )
Solvent
0.5
Petroleum E t h e r (30'-60') Diethyl Ether Water 2-Propanol 3A Alcohol Chloroform 95% E t h a n o l Benzene Methanol
0.8 >500,
1.7 14.1 19.3 53.8 1.2 139.4
2.11
X-ray C r y s t a l P r o p e r t i e s The x-ray powder d i f f r a c t i o n d a t a o b t a i n e d f o r a sample of r e f e r e n c e s t a n d a r d trimethobenzamide h y d r o c h l o r i d e a r e g i v e n i n Table I11 ( 9 ) . The o p e r a t i n g c o n d i t i o n s of t h e i n s t r u m e n t a r e g i v e n below. Instrumental Conditions: G e n e r a l E l e c t r i c Model XRD-6 S p e c t r o g o n i o m e t e r Generator: Tube t a r g e t :
50 KV, 12-112 MA Copper
5 62
TRIMETHOBENZAMIDE HYDROCHLORIDE
Cu K, = 1.542 2 Detector s l i t M.R. S o l l e r s l i t 3' B e a m s l i t 0.0007" Ni f i l t e r 4' t a k e o f f a n g l e Scan a t 0.2O 28 p e r m i nut e A m p l i f i e r g a i n - 16 c o a r s e , 8.7 f i n e Sealed proportional counter t u b e and DC v o l t a g e a t p l a t e a u P u l s e h e i g h t s e l e c t i o n EL 5 volts; Eu - Out Rate meter T . C . 4 2000 C I S f u l l s c a l e C har t s p e e d 1 i n c h p e r 5 m i nut es P r e p a r e d by g r i n d i n g a t room t empe r a t u r e
Radiation: optics:
0.1'
Goniometer: D e tec t o r :
R e co r d e r :
Samples :
T a b l e I11 I n t e r p l a n a r S p a c i n g s from Powder D i f f r a c t i o n Data f o r Trimethobenzamide H y d r o c h l o r i d e 1 2 -------a 28 dl(Ao) 1/1 28 d(Ao> I/I, 18.2 7.23 6.21 6.08 5. 86 5.64 5.33 5. 05 4.97
4.86 12.24 1 4 .2 6 14.58 15.13 15.70 1 6 .6 4 17.55 17.86 'd 2
30 6 75 35 100 19 64 12 12
31.13 31.30 31.75 32.50 34.44 35.30 35.56 36.00 36.96
= (interplanar distance)
111,
=
nh 2 Sin
2.87 2.86 2.82 2. 75 2. 60 2.54 2.52 2.49 2. 43
8 7 19 29 18 3 3 4 2
e
r e l a t i v e i n t e n s i t y ( b a s e d on h i g h e s t i n t e n s i t y o f 100)
563
K. W. BLESSEL, B. C. RUDY, A N D B. Z . SENKOWSKI
18.36 19.18 19.49 20.20 20.68 20.96 21.38 22.27 22.63 23.03 23.53 24.66 25.02 25.62 26.12 26.48 27.08 27.86 28.16 28.96 29.96 30.56
4.83 4.63 4.55 4.40 4.29 4.24 4.16 3.99 3.93 3.86 3.78 3.61 3.56 3.48 3.41 3.37 3.29 3.20 3.17 3.08 2.98 2.93
3 4 25 36 18 14 45 63 34 68 35 45 16 31 57 32 55 10 5 16 31 8
37 - 4 6 37.96 38.36 38.94 39.50 39.85 40.46 41.00 41.48 41.96 42.82 43.72 45.00 45.30 45.76 46.18 46.72 47.28 47.54 48.46 49.48 51.15
2.40 2.37 2.35 2.31 2.28 2.26 2.23 2.20 2.18 2.15 2.11 2.07 2.01 2.00 1.98 1.97 1.94 1.92 1.91 1.88 1.84 1.79
2 5 3 7 9 5 6 4 7 3 7 8 4 4 3 4 4 6 4 4 3 7
2.12
D i s s o c i a t i o n Constant The a p p a r e n t pKa o f t r i m e t h o b e n z a m i d e hydroc h l o r i d e was d e t e r m i n e d by a p o t e n t i o m e t r i c t i t r a t i o n i n The v a l u e o b t a i n e d w a s aqueous s o l u t i o n w i t h 0.02M KOH. 8 . 2 7 - 0 . 0 3 (10).
+
3.
Synthesis The r e a c t i o n s e q u e n c e shown i n F i g u r e 7 w a s u s e d t o produce 1 k - l a b e l l e d t r i m e t h o b e n z a m i d e h y d r o c h l o r i d e and i s a l s o one of t h e s y n t h e t i c r o u t e s t o produce t h i s material(l2).
4.
S t a b i l i t y Degradation Trimethobenzamide h y d r o c h l o r i d e h a s been shown t o b e s t a b l e when h e a t e d a t 100°C i n a c i d , a l k a l i n e o r n e u t r a l s o l u t i o n ( 1 2 ) . I t was a l s o found t o b e s t a b l e when s t o r e d a t room t e m p e r a t u r e € o r a p e r i o d i n e x c e s s o f f i v e y e a r s (13).
5.
Drug M e t a b o l i c P r o d u c t s A s t u d y of t h e metabolism o f trimethobenzamide hydroc h l o r i d e i n dogs h a s b e e n c a r r i e d o u t u t i l i z i n g a
5 64
TRIMETHOBENZAMI DE HYDROCHLORIDE
Figure 7 Synthesis of 1 4 C - label led Trimethobenzamide Hydrochloride
,
cn
'i-CH
2 -CH 2 -0
0
C0Cl