Sterols. LIII. The Structure of the Side Chain of Sarsasapogenin

Abstract

A study has been made of the behavior of certain aliphatic organic acids chiefly typical hydroxy, unsaturated, or keto, toward reduction catalyzed by Raney nickel and in the presence of sodium hydroxide and under high hydrogen pressure.2. At temperatures below 250°and hydrogen pressures not exceeding 330 atmospheres, a-and -hydroxy acids are not affected, whereas ß-hydroxy acids are converted into the corre-sponding unsubstituted acids.3. The unsaturated acids studied were hydrogenated rapidly at temperatures of 100°, or less. 4. a-and y-keto acids were hydrogenated with ease to the corresponding hydroxy acids at quite moderate temperatures. 5. Of particular importance was the conversion, in alkaline solution at 250°and under a hydrogen pressure of 330 atmospheres, of formic acid into methane and carbon dioxide.

STEROIDAL SAPOGENINS. VII.1 EXPERIMENTS IN THE HECOGENIN SERIES (PART 1)

“…and 22-isoallospirostan-3/3-ol (tigogenin) (Ha). Since this first observation already was in complete contrast to Marker's report (2), 22-isoallospirostan-3j8-ol (Ha), 22-isoallospirostan (desoxytigogenin) (lib) (6) and 22-isoallospirostane-3|S, 12diol 3,12-diacetate (lie) (rockogenin) were similarly brominated, but in this instance only a 23-monobromo derivative was formed. From these observations it appears that the steroidal sapogenin side chain can be dibrominated in the normal (neo) configuration, but only monobrominated when it possesses the 22-iso configuration.…”

“…Chem., preceding paper. 2 The conversion of A5-22-isospirosten-3;3-ol-12-one (botogenin) to A5-pregnen-30,17adiol-12,20-dione has been reported by Marker (J. Am.…”

Steroidal Glycoalkaloids: Isolation, Structure, Analysis, and Biosynthesis

“…(b) Acid-catalyzed isomerization: Two other acid catalyzed reactions have been observed for sapogenins and have some relevance for SGAs. Marker and Rohrmann [101] found that sarsasapogenin (21) on being refluxed with alcoholic HCl yielded smilagenin (22) (Figure 13). Wall et al [102] established that the reaction is reversible and both compounds give a mixture containing approximately 20% sarsasapogenin and 80% smilagenin.…”

Complete Assignment of the1H and13C NMR Spectra of Steroidal Sapogenins: Smilagenin and Sarsasapogenin

“…Originally identiÐed as C 26 compounds, they were revised to in 1935, 3 and their C 27 side-chains were correctly identiÐed by chemical analysis in 1939. 4 Smilagenin, (25a f )-5b-spirostan-3b-ol (1), and sarsasapogenin, (2), (25b f )-5b-spirostan-3b-ol are stereoisomers di †ering in conÐguration at C-25. Smilagenin is the 25R (25D) form and sarsasapogenin the 25S (25L) form.…”