5818
V. R.
hfATTOX,
R. B. TURNER, W. F. MCGUCKIN, E. J. H. CHU
222' (reportedla m.p. 219-22l0, reported's m.p. 223225O), was obtained by crystallization from chloroform-.
AND
E. C.KEXDALL VOI. 74
petroleum ether. -4nal. for C Z 2 ~ 3 2 0c, 5 :70.18; H , 8.57. Found: " 70'34; H' 8'52' ROCHESTER, MINNESOTA
(15) J. von Eum, A. Lardon and T. Reichstein, ibid., 97, 1287 ( 1944).
:COSTRIBUTION FROM SECTION OF BIOCHEMISTRY, MAUOCLINIC]
Steroids Derived from Bile Acids. XX. Degradation of 3a,9a-epoxy-ll-KetonorAcid' cholanic Acid to 3~~,9a-Epoxy-ll-ketoetiocholanic BY VERNONR.
JfATTOX,
RICHARD B. TURNER, WARRENF. MCGUCKIN, EDITHJ. H. EDWARD C. KENDALL
C H U AND
RECEIVEDMay 16, 1952 Methyl 3a,9a-epoxy-ll-ketonorcholanatehas been degraded to 3a,ga-epoxp-l I-ketoetiocholanic acid by a combination of the Barbier-Wieland and Hoehn-Mason procedures in a yield of 36%.
Cleavage of the oxide ring in methyl 3a19a- ether was inert toward oxidation it was advanepoxy-11-ketocholanate with hydrogen bromide tageous to degrade the side chain to the etio acid and degradation of the 3a-hydroxy steroid thus before restoration of the reactive hydroxyl group obtained to give 3a-acetoxypregnane-11,20-dione a t C-3. However, in a study of the cleavage of the and 3a-acetoxy-11-ketoetiocholanicacid have been oxide ring a t the nor, bisnor and etio ester stages reported.2 Degradation of the side chain was it was found that there was a progressive decrease achieved by a modification of the Barbier-Wieland in the reactivity of the oxide ring toward hydrogen method, and the pregnane was converted into the b r ~ m i d e . ~The conditions which were satisfactory acid etio acid by the Hoehn-Mason scheme. This for the ester of 3a,9a-epoxy-ll-ketonorcholanic paper describes the use of these procedures for con- failed to open the oxide completely when the ester version of methyl 3a,9a-epoxy-ll-ketonorcholanate of the etiocholanic acid was used; more severe conditions3 led to formation of the 3,12a-dibromointo 3C Y , 9a-epoxy- 11-keto etiocholanic acid. 11-keto derivative of etiocholanic acid. OH
Experimental4 3~,9~u-Epoxy-l I-keto-23,23-diphenylnorcholan-23-01 (II).-A solution of 19.49 g. of methyl 3a,9a-epoxy-l1-ketonorcholanatein 100 ml. of benzene was added slowly with mechanical stirring t o 200 ml. of an ethereal solution of 1.5 M phenylmagnesium bromide in a flask immersed in a bath a t -20'. The solution of steroid was added at such a ra!e that the temThe reaction perature in the flask was 0 to 3 mixture was stirred for 3 hours at 0", the flask was sealed and stored in an ice-bath. After 24 hours the salution was poured over ice and ammonium chloride, the organic phase was washed and concentrated to dryness and the residue was crystallized from acetone-methanol. The volatile products were removed from the filtrate by steam distillation and more material was seDarated from acetone-methanol: total yield 81%: The analqical sample melted at 152-153', [a]D+61 1. .4nal. Calcd. for C86H4403: C, 81.99; H , 8.65. Found: C, 82.22; H, 8.55. Ja,Qa-Epoxy-23 ,23-diphenyl-A2*--norcholen11-one (III).-A solution of 5.39 g. of 3a,9cuepoxy 11-keto- 23,23-diphenylnorcholan-23-01 in 10 ml. of acetic acid was refluxed for 1 hour and poured into water. The precipitate was collected, dried and recrystallized from acetonemethanol; wt. 5.02 g. (97%), m.p. 136-139:. The analytical soample melted a t 136.5-137.5 . [ol:D 1-172 i 2 . Anal. Calcd. for CzhH1202: C, 84.97; H , 8.56. Found: C, 85.12: H, 8.61.
.
OH
*
XVA, R = H IYB, R = CH,
VI
$€I3
CH=CHCeHs
c-=o
c=o
' '-\ ,-
VI1
I
I
I
--+
' A /--
\TI1
-
COIR
4
\\
+
I
i /'-
IXA, R = H IXB. R = CHs
(1) The work reported in this paper was carried out in 1943-1946. (2) R. B. Turner, V. R. Mattox, W. F. McGuckin and E. C. K e n dall, TEISJOURNAL, 74, 5814 (1932).
to Mr. William Saschek, Department of Biochemistry, Columbia University, for microanalyses. Optical rotations were taken in chloreform (c 1) a t 27 i2 O
-
Dee. 5, 1952
DEGRADATION OF ~ C Y , S C ~ - E P1-KETONORCHOLANIC OXY-~ ACID
5819
form and 30 ml. of methanol was cooled in an ice-salt-bath, 3&~-Epoxy-ll-ketobisnorcholanic Acid (IVA).-3a,9aEpoxy-23,23-diphenyl-A22-norcholen-ll-one (33.1 g.) was and 22.5 millimoles of ozone was passed into the solution. oxidized as described in the preparation of 3a,Qa-epoxy-l1- Twenty grams of zinc dust and 40 ml. of 95% acetic acid ketonorcholanic acid.2 The product, crystallized from ace- were added and the solution was stirred until it gave a negatone, separated in three crops and was dried to constant tive starch-iodide test. The zinc was removed by filtraweight at 105"'; I , 17.89 g., m.p. 181-182"; 11, 1.91 g., tion, the solution was concentrated and the residue was m.p. 179-181 ; 111, 0.28 g., m.p. 178-180"; total crude crystallized (4.48g., m.p. 123') from methanol. Volatile yield, 79%. A sample of the acid that had been crystallized products were removed from the filtorate with steam and from acetone and dried a t about 40' melted at 78-80' with moreoftheproduct(1.76g.,m.p. 123 ; 0.18g.,m.p. 120") effervescence, recrystallized on the slide and remelted at was crystallized from methanol. The total crude yield 182-184'. The sample lost 13.3% in weight when dried was 93%. Purified material melted a t 126-127", [ a ] ~ at 105". Calculated for 1 mole of acetone, 13.9%. The $167 f: 1". dried sample melted a t 182.5-183.5", [ a ] D +69 =I= . ' 2 Anal. Calcd. for CziH30Oa: C, 76.32; H, 9.15. Found: Anal. Calcd. for Ct~H3204:C, 73.30; H, 8.95. Found: C, 76.22; H , 8.96. C. 73.37; H.8.88. 3a,9a-Epoxy-2 1-benzylidenepregnane-1 1,20-dione (VIII). -3a,9a-Epoxypregnane-l1,20dione (3.30g.) was dissolved . Methyl 3a,9a-Epoxy-il-ketobisnorcholanate(I-).3a,9a-Ep0~y-ll-ketobisnorcholanic acid (1S.9 g.) was es- in 25 ml. of hot methanol, the solution was cooled to room terified in 300 ml. of methanol, which contained 3 ml. of temperature and 3.0 ml. of benzaldehyde (freshly distilIed) concentrated sulfuric acid. The solution was refluxed for was added. After addition of a solution of sodium methyl8 hours, and cooled in an ice-bath. Crystals (16.38 g., ate (1.0 g. of sodium in 10 ml. of methanol) the mixture was m.p. 138-139") which separated were filtered and washed allowed to stand a t room temperature for 48 hours. The with water. Concentration of the filtrate gave 2.56 g. of product which separated was filtered and washed with cold ester (m.p. 137-138'), and a third crop (0.68g., m.p. 137- methanol. After recrystallization from chloroform-meth138') was obtained after dilution with water, extraction anol (1:lO) the material (3.74g.) melted a t 194-195", fa]^ with benzene, concentration and crystallization fro? cold +91 f 2'. methanol. The total yield was 99.5%, [a]D4-77 f 2 . Anal. Calcd. for C28H3403: C, 80.34; H , 8.19. Found: A-nul. Calcd. for CzaHsaO4:C, 73.76; H , 9.15. Found: C, 80.43; H, 8.31. C, (4.05;H , 9.16. 3a,9a-Epo~y-ll-ketoetiocholanic Acid (IXA) .-A solution of 4.18 g. of 3a,9a-epoxy-21-benzylidenepregnane-11,203~,9~-Epoxy-ll-keto-22,22-diphenylbisnorcholan-22-ol (V).-Methyl 3a,9a-epoxy-ll-ketobisnorcholanate (3.759.) dione in 30 ml. of chloroform, 15 ml. of ethyl acetate and 15 as a dry powder was added in portions with mechanical ml. of methanol was cooled to 0' and 11 millimoles of ozone stirring to 29 ml. of an ethereal solution of 2.1 molar phenyl- was passed into the solution. Four grams of zinc dust and magnesium bromide and 29 ml. of dry ethyl morpholine a t 20 mi. of 85% acetic acid we;e added and the solution was 0'. The solution, protected from moisture with a calcium stirred for 20 minutes at 0 . The zinc was filtered off, chloride tube, was kept a t room temperature for 24 hours washed with ether, the combined filtrates were washed with and a t 45-50' for 48 hours and was then poured over ice, in water and concentrated under reduced pressure. The dilute acetic acid. The aqueous phase was extracted thrice residue was dissolved in 30 ml. of ethyl acetate and 20 m t with benzene, the extracts were combined, washed with di- of acetic acid, and t o the solution 15 ml. of 7.7 N periodie lute acetic acid, dilute sodium hydroxide solution and with acid and 1.5 ml. of concentrated sulfuric acid were added. After 3 hours at room temperature the solution was diluted water. The solvent was removed and 4.19 g. (%%).of crystals, m.p. 201", was obtained from methanol which with water, the product was extracted with ether, and the contained a small amount of acetone. A purified sample ethereal solution was washed with water and with 0.5 N potassium hydroxide. Acidification of the alkaline solution melted a t 204-205", [a]D4-93 f.'1 Anal. Calcd. for C U H ~ Z O ~ . ~ / ~C,H 80.43; ~ O : H , 8.54. liberated the etiacholanic acid which was filtered off, washed and dried, wt. 2.92 g. (88%'0;, m.p. 232-233". Found: C, 80.48,80.57;H , 8.65,8.51. Repeated recrystallization of the acid from ether-petroleum 3~,9~-Epoxy-22,22-diphenyl-A~(2*~-bisnorcholen-ll-one ether did not raise the melting point, [a]D+ l f 6 6". (VI).-A solution of 2.23 g. of 3a,9a-epoxy-ll-ket0-22,22Anal. Calcd. for C20H2804; C , 72.26; H, 8.49. Found: diphenylbisnorcholan-22-01 in 10 ml. of acetic acid was refluxed for 2 hours and cooled. The ethylene, after recrys- C. 72.33: H. 8.49. ' Me&l 3a,9a-Epoxy-l I-ketoetiocholanate (ID).-The tallization from acetic acid, weighed 1.98 g. (92%) and ester prepared from 3a,9a-epoxy-ll-ketoetiocholanicacid melted a t 197-198", [ a ]+275 ~ i2 ' . Anal. Calcd. for C3tHcoO.: C, 84.95; H , 8.93. Found: with diazomethane in ether and crystallized from cold methanol, melted a t 132-133'. . rollD f 2". _ . 4-111 C, 84.86; H , 8.64. 'Calcd. for CZIH~OO,: C, 72.80; H , 8.73. Found: 3a,9a-Epoxypregnane-I 1,20-dione (VII).--A solution of C,Anal. 72.86; H,8.69. 10.0 g. (20.8 millimoles) of 3a,9a-epoxy-22,22-diphenylAZJ(22)-bisnorcholen-ll-one in a mixture of 30 ml. of chloro- ROCHESTER, MINN.
*
