Studies on Bile Salts of Toad (Bufo vulgaris japonicus). XI. Formation of Norcholic Acid from Δ²³-3(α), 7(α), 12(α)-Trihydroxycoprostenic Acid C₂₇H₄₄O₅ and Stem Acid C₂₇H₄₆O₂

抄録

A new unsaturated bile acid, m.p. 176-179°, was isolated from the bile of toad (Bufo vulgaris japonicus). This acid corresponds to formula C₂₇H₄₄O₅, has [α]12D=+29.13 and gives Hammarsten-Yamasaki's tests. The methyl ester acetate yields, by oxidation and then hydrolysis, the well known norcholic acid. It is certain that double bond in the side chain is situated between the positions of C₂₃ and C₂₄. The hydrogenated acid is identical with trihydroxycoprostanic acid which was obtained by Haslewood from the bile of Alligator mississippiensis. The structure of this acid, m.p. 176-179°, will be Δ²³-3(α), 7(α), 12(α)-trihydroxycoprostenic acid. Some derivatives of the acid were prepared.