product of digestion, although a sinall amount of the heptapeptide was also present. This finding provides additional evidence for the view that the C-terminal alanine groups are not essential for the biological activity of insulin. IIEPARTMENT O F
BIOCHEMISTRY
I'NIVERSITY OF CALIFORW i 1 IEVAV lrARRIS RFRKCLEY,CALIFORNIA Ctrorr Hii) L r RECEIVEDAPRIL80, 1952
THE STRUCTURE AND SYNTHESIS OF A NEW THIAZOLIDONE ANTIBIOTIC' Sir:
We have established the structure ( - )2-(5-carbo.rypentyl)-4-thiazolidone(I) for a new Streptonzy/.e2 antibiotic2 exhibiting in vifro antituherctilar acti vi t v.
s I
-
?It
(CFI),
co K
CH2 AH \C/
solution gave acetamide as well as a mixture of acidic products. However, when the desulfurization was carried out on the ester (11) in anhydrous dioxane under mild conditions, desthio-I1 was obtained in good yield. It crystallized from etherpetroleum ether as colorless needles, m.p. 31-32'. iA,nnl. Calcd. for C10HI9O3N:C, 59.67; H, 0.52; N, 6.96. Found: C, 59.55; H, 9.5s; N, (i.87.) Alkaline hydrolysis of the desthio coinpound gave w-aminoheptanoic acid, colorless plates from ace(Anal. tone-methanol-wa ter, in.p . 193-1 94". Calcd. for C7HI5O2N: C, 57.90; H, 10.41; S , 9.65. Found: C, 58.11; H, 10.34; N, 9.57.) Desthio-I1 was shown to be methyl w-acetamidoheptanoate (V) by comparison with an authentic sample prepared by hydrogenation of methyl w cyanocaproate in acetic anhydride. CHBCONI-I--CII?-( CH~)~-COZCH~
v
Oxidation of 1in acetic acid solution with hydrogen peroxide gave the microbiologically inactive 0 sulfone (VI), crystallized from water as colorless m p . 143', [ c Y ] ~+43 ~ D (c 1, methanol). needles, Reaction of I in ether solution with excess diazomethane gave the microbiologically active methyl (Anal. Calcd. for C9Hlj05NS: C, 43.37; H, 6.07; ester (II), crystallized from ether-hexane as color- N, 5.62; S, 12.85. Found: C, 43.65; H, 6.18; N, less needles, m.p. 53-54', [ C ~ ] ~ ' D-50.go, (c 1, meth- 53.5; S, 13.10.) The infrared spectrum of VI (Nuanol). (Anal. Calcd. for C10H1703X3: C, 51.92; jol mull) exhibits a strong band in the region 1120 H, 7.41; N, 6.06; S, 13.86; CH30, 13.41. Found: to 1160 ern.-', characteristic of sulfone^.^ Dissolving VI in N sodium hydroxide a t 27' reC, 51.92; H, 7.43; N, 6.15; S, 13.62; CHBO, 12.90.) Ultraviolet absorption studies of I (in sulted in extensive hydrolysis within a few minutes methanol) and 11 (in 2,2,4-trimethylpentae) in the as evidenced by the rapid formation of titratable region 210400 mp revealed only end absorption. sulfite. Mild hydrochloric acid hydrolysis of VI yielded The infrared spectrum of I (Nujol mull) exhibits products identified as sulfur dioxide, ammonium two characteristic carbonyl bands near 1640 and 1710 cm.-I. Comparable bands a t 16SO and 1720 chloride and IV. Comparable acid hydrolysis of cm.-' are apparent in the spectrum of I1 (chloro- I also gave ammonium chloride together with a form solution). The lower frequency carbonyl mixture of products identified as IV and a sulfurband has been attributed to a carboxamide and containing dicarboxylic acid believed to be VII, the higher frequency carbonyl band to an aliphatic which was purified as the dimethyl ester (VIII). RO~C-CHa-S-CH=CH-( CH2)4--CO?R carboxyl grouping. Hydrogen bonded N-H abVU, R = H sorption has been assigned to bands a t 3140 cm.-' in 1and 3170 cm.-' in IT. A cleanly resolved band 17111, R = CH3 near 3450 cm.-' (free X-H) is apparent in the Compound VIII is a colorless, odoriferous oil, b.p. spectrum of 11. I rapidly loses optical activity in dilute alkali to 162-168' (0.4 inni.), 7zz51) 1.4830, d2j41.128. The 226, t 4600 (in give the racemate, obtained in two crystalline mod- light absorption properties, 2,2,4-trimethylpentane), are consistent with the ifications: (1) from water as colorless needles, m.p. 122-123' and (2) from chloroform as colorless nee- above formulation.fi (Anal. Calcd. for CllHI,O48: Theinfraredspectraof (l), (2) C, 33.64; H, 7.36; S, 13.02; CHBO, 23.2; M.R., dles, m.p. 116-117'. and I in dioxane solution are indistinguishable. 68.9. Found: C, 53.60; H, 7.40; S, 13.30; CHxO, 22.3; 2$f.R., 62.6.) Mild alkaline hydrolysis of 11gave racemic 1. The structure of I was confirmed by synthesis. Oxidation of I with alkaline permanganate or dilute nitric acid gave a crystalline dibasic acid, m.p. Methyl w-aldehydopimelate (IX)' was condensed 104', unequivocally identified as pimelic acid (111) with mercaptoacetaniide in benzene in the presence of p-toluenesulfonic acid to give racemic IT. Saby comparison with an authentic sample. Mercuric chloride hydrolysis of I was accompa- ponification of the synthetic ester yielded racemic I nied by rapid loss of optical activity and liberation of which was resolved by means of fractional crystallian aldehyde identified as the semi-aldehyde of pi- zation of its brucine salts. Synthetic I, m.p. 139(4) Lit. m p. 186-187". A. Ifawasse, ibid , 36, 1369 (1902); 0 melic acid (IV), characterized as the oxime, m p . Wallach, A?&%.,31Z, 205 (1900). ltO-lllo3 and by oxidation to pimelic acid (111). ( 5 ) (a) K. C. Schreiber, A n d . Chem., Zl,1168 (1949). (b) D. BarDesulfurization of I with Raney nickel in ethanol nard, J. M . Fabian and H . P. Koch, J . Chem. SOC.,2442 (1949). 11
1,R = H IT, R = CH?
( I ) Since the completion of this work, we have learned t h a t thi5 dntibiotic (actithiazic acid) has been independentlv i s o l d l e d d n d ,yn thesized by P group Jt the Abbott 1,aboratories (2) i 3 A Sobin, T X IT~O U R V ~ I 74, 0000 (1'152) (J) \I Kcrshhriiin. R?i , 60, q O L ( I < l L i i
( 6 ) K. Bowden, E. A. Braude and E. R. H . Jones, ibid., 948 (l94G). t i l IX was prepared by a modified Rosemund reduction (5Wo pallailiiim u r i call~uiicatalyst) of inethyl pimelyl chloridein refluxing xylene solniioii I S ~listillml ;at 70' ( 0 .5 rnin 1, ar. :i colorless l i q i i i d . n ? i t , 1 .WiI,
June 5, 19.52
COMMUNICATIONS TO THE EDITOR
2947
anhydrous chloroform has an additional band a t 4500 A. ( E m 36) which is characteristic of a-diIV. M. MCLAMORE carbonyl compounds. Chemically the hydrates WALTERD. CELMER behave as typical aldehydes. Positive Schiff and RESEARCH LABORATORIES VIRGILV.BOGERT silver mirror tests are observed and three derivaCHAS. PFIZER AND C O . , INC. FRANK C. PENNINGTON tives involving the aldehyde group have been preBROOKLYN 6, NEWYORK I. A . SOLOMONS pared from cortisone aldehyde, the dimethyl and RECEIVBD MAY9, 1952 diethyl acetals (VII, VIII) and the diacetate (IX). The aldehyde hydrates have approximately the same activity as cortisone and hydrocortisone in ALDEHYDES DERIVED FROM CORTISONE AND rat liver glycogen deposition tests.' The nitrone HYDROCORTISONE and diacetate in the cortisone series are also active, Sir: while the acetals appear to be inert. I t has, furCortisone (I) and hydrocortisone (X), Kendall's compounds E and F, have been converted to the thermore, been noted that cortisone and hydrocorcorresponding 21-aldehydesI A4-3,11,20-triketo-l7a- tisone aldehyde hydrates cause adrenal atrophy hydroxypregnene-21-a1 (V) and A4-3,20-diketo- and thymus involution similar to that resulting 11p, 17a-dihydroxyprenene-21-a1(XIII), which are upon administration of the parent hormones.2 The approximate equivalence in biological activity biologically active. On treatment of cortisone (I) with p-toluenesul- of cortisone and hydrocortisone with the correfonyl chloride a mixture of the pyridinium @-tolu- sponding 21-dehydro compounds is in contrast to enesulfonate and chloride (11, 111) was obtained. results with desoxycorticosterone and the related The latter salt was treated with p-nitrosodimethyl- 21-aldehyde. This aldehyde is only one twentyaniline to give the nitrone (IV), isolated in two fifth as effective as desoxycorticosterone in the forms, red plates and yellow needles, having identi- Everse-deFremery work test. (1) Several modifications of the procedure of Pabst, Sheppard and cal decomposition points. The nitrone was hydro-
140°, [ a ] " ~-51.4, was identical with the antibiotic obtained from the Streptomyces fermentation.
Kuizenga (Endoc~inology,41, 51 (1947)) have been employed by Drs. C. C. Porter and R. H. Silber of the Merck Institute for Therapeutic Research, to whom we are indebted for the reported results. (2) We are obliged to Dr. C. A. Winter, Merck Institute for Therapeutic Research, for these tests. (3) H . Reich and T. Reichstein, Helo. C k i m . Acta, 22, 1124 (1939).
COR
E. F. ROGERS RESEARCH LABORATORIES W. J. LEANZA MERCK& Co., INC. J. P. CONBERE K. PFISTER 3 R D RAHWAY, AT. J. RECEIVED MAY19, 1952 X I I1
c=o c=o c=o c=o c=o c=o c=o c=o
R
CHIOH CHzPy+OTsCHtPy +C1111 CH=N(O) CeH4N(CHa)z IV V CHO CH(0H)z VI CH(0CHa)z VI1 VI11 CH(OCzH6)z CH(0COCHs)z IX c-0 X CHOH CHzOH X I CHOH CHzPy "C1XI1 CHOH CH=N(O)CsH4N(CHs)z XI11 CHOH CHO XIV CHOH CH(0H)z
M . p., OC.
285-290 dec. 290-291 dec. 189-190 dec. 210-215 dec. C Q . 225 dec. 142
c=2)
$231°
A NEW STREPTOMYCES ANTIBIOTIC'
Sir : A new antibiotic, exhibiting highly specific in vi+18Z0 tro activity against Mycobacteria, has been isolated $176' from a species of Streptomyces. The antibiotic 77 $165' + 990 may be recovered by successive n-butanol extrac169 tions of the culture broth after filtration from the 295-296 dec. $232O mycelium a t p H 2.0. The butanol extracts are 186-188 dec. combined and the acidic antibiotic extracted with sodium carbonate solution. The alkaline solution 155-160 dec. +155O is adjusted to p H 4.5, and then repeatedly exlyzed by dilute acid to cortisone-21-aldehyde (V), tracted with butyl acetate. Evaporation of the which crystallized from aqueous acetone as the butyl acetate leaves a dark brown sirup which is colorless hydrate (VI). (Anal. (after drying a t 25' dissolved in hot ethylene dichloride, treated with (1 mm.) 4 hr.) Calcd. for C21Hz80a: C, 67.00; activated carbon, and filtered. On cooling, the anH, 7.50. Found: C, 67.01; HI 7.75). Theyellow tibiotic crystallizes in long white needles. Recrysfree aldehyde was regenerated from the hydrate tallization can be effected from hot water, warm by several hours drying a t 110' (1 mm.). (Anal. acetone, or methanol. Calcd. for C21H2605: C: 70.36; HI 7.31. Found: This new antibiotic is a monobasic acid, pK 5.1. C, 70.09; H, 7.52). Titration molecular weight data are in agreeBy an analogous procedure, hydrocortisone (X) ment withand the formula C9H1603NS, m.p. 139-140", was converted Via the pyridinium chloride (XI) [ a ] " ~-54 (c 1, methanol). (Anal. Calcd. for and nitrone (XII) to hydrocortisone-21-aldehyde CgHx03NS: C, 49.77; HI 6.91; N, 6.45; S, 14.75. hydrate (XIV). (Anal. Calcd. for C21H3006: C, Found: C, 49.96; H I 7.09; N, 6.51; S, 14.83). 66.64; H, 7.99. Found: C, 66.94; H, 7.69). Solutions of the pure material exhibit a blue fluoThe ultraviolet absorption spectra of cortisone rescence on exposure to ultraviolet light. There aldehyde hydrate (max. 2380 A., Em 15,700) aFd is no characteristic ultraviolet spectrum. The hydrocortisone aldehyde hydrate (max. 2420 A,, (1) Since the completion of this work, we have learned t h a t this E , 16,000) in methanol resemble those of cortisone antibiotic (actithiazic acid) has been independently isolated and s y n and hydrocortisone. Cortisone free aldehyde in thesized by a group a t Abbott Laboratories.
