Studies on the Constituents of Asclepiadaceae Plants. XLVIII. 5α, 6α-Epoxycaudatin, a New Polyoxypregnane Derivative from Cynanchum caudatum MAX.

A new polyoxypregnane derivative, 5α, 6α-epoxycaudatin, was isolated from Cynanchum caudatum MAX. and its structure was elucidated on the bases of physical data and chemical reaction. This compound is a probable intermcdiate in the biosynthesis of 5, 6-glycolic compounds. Kidjoranin was also isolated from this plant for the first time.