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38.56
STEROIDAL SAPOGENINS, 173. 16-DEHYDROPREGNEN-5-0Lc3-DIONE-12,20 FROM RICOGENIN, A NEW STEROIDAL SAPOGENIN h%:
extensive search for naturally occurring steroidal sapogenins having substituents in ring C which may be utilized for the synthesis of cortisone, the anti-arthritic hormone, a new saponide, riconin, m.p. 285-289' dec., was isolated from the mixture of glycosides occurring in Dioscorea 11Itzcrostachyn. In
ail
c o
H
UJ
d
16-Dehydropregnen-5-01-3-dione-l2,20
Vol. 71
Calcd. for C;*HseOh: C, 74.8; H, 8.2. Found: C, 74.0;
H, 81.
BOTANICA-MEX, S. A. PLAZA DE SAN PABLO NO. 6
RUSSELLE. MARKER TEXCOCO, MEXICO HOTELGENEVE,MEXICOCITY RECEIVED OCTOBER 4, 1949
ALLO-PREGNAN-3,12,2O-TRIONE
Sir : The current interest in Kendall's substance E for rheumatoid arthritis has stimulated great in-
C
C
/JJJ
HO
Pseudobotogenin
Hydrolysis of riconin with alcoholic hydrochloric acid terest in the search for starting materials for its gave ricogenin, m.p. 225-227'. Anal. Calcd. for C~Hlo06: synthesis. Recently, Marker reported the possiC , 72,9; H, 9.1. Found: C, 72.9; H, 9.1. Ricogenin formed a diacetate, m.p. 195-197', and con- bility of utilizing a steroidal sapogenin, botogenin, tains three ketonic groups having the same side-chain isolated from Dioscorea Mexicana. Its degradastructure as kryptogenin. Anal. Calcd. for C3iH~01: tion product was 5-pregnen-3(p)-01-12,20-dione, C, 70.4; H, 8.1. Found: C, 70.2; H, 8.2. characterized by conversion to allo-pregnan-3,12,Treatment of ricogenin with acetic anhydride a t 195' for 20-trione) m.p. 264'. The latter was identical eight hours followed by hydrolysis gave pseudoricogenin, from the degram.p. 220-222'. Anal. Calcd. for CnH3804: C, 76.0; H, with allo-pregnan-3,12,20-trione2 9.0. Found: C,76.2; H,9.O. dation of hecogenin. When heated with alcoholic hydrochloric acid for fifteen We have prepared an authentic sample of allo-pregnanminutes, pseudoricogenin was converted into ricogenin, by a n entirely different route and have found m.p. and mixed m.p. 225-227'. Catalytic reduction of the 3,12,20-trione completely different from the trione from hecogenin. diacetate of pseudoricogenin, using palladium-on-barium it Desoxycholic acid has been degraded to 12(a)-acetoxyprosulfate as catalyst, saturated only the conjugated double gesterone (I), m.p. 181°, [ C Y ] ~ D +215", [(Y]%oI +269" bond in ring D, giving the diacetate of pseudobotogenin. (chloroform), absorption maximum at 240mp(log e 4.14 in This product upon alkaline hydrolysis followed by iso- ethanol) . 3 This compound (I) upon sodiumalcohol reducmerization with alcoholic hydrochloric acid gave botogenin, followed by chromic acid oxidation furnished allom.p. and mixed m.p. 260-262O.s Anal. Calcd. for Cd&oO4: tion pregnan-3,12,20-trione (11). m.p. 206-208', [(Y]*~D +184", Ci75.7; H, 9.4. Found: C, 75.5; H, 9.4. [ 0 1 ] +224O ~ ~ ~ ~ (chloroform), ~ nomaximum a t 240mp. Anal. Acetylation of this product gave botogenin acetate, Calcd. for CzlH3oOs: C, 76.3; H, 9.2. Found: C, 76.0; H, m.p. and mixed m.p. 246-248". Anal. Calcd. for 8.9. The reduction was also accomplished with hydrogen '&Hd205: C, 74.0; H, 9.0. Found: C, 74.1; H, 9.3. and Adams catalyst in acetic acid; subsequent hydrolysis The pseudobotogenin diacetate produced by the catalytic and oxidation gave the same product (11). The course of reduction of the diacetate of pseudoricogenin was oxidized these methods of reduction has been shown previously' with chromic anhydride in acetic acid, followed by hydrolysis,' giving 16-dehgdropregnen-5-ol-~-di0ne-12,20 (1) Marker, THISJOUXNAL, 71, 3656 (1949). (2) Marker, Wagner and co-workers, ibid., 69, 2167 (1947). acetate, m.p. and mixed m.p. with the product Hepared (3) Shoppce nnd Reichstein, RcZv. Ckim. Acre, 94, 361 (1941). from naturally occurring botagenin, 22S-2P7°, Anal. (1) Mcrker, T&d I@wWnnz,V i r $@$Q &?4'a)a
(4) Mnrker and Wittlc, Tme JOIJERA~, 89, 2704 (1987); Butennndt rod Weischer, Baed M, 4094 (1086),
