The structural formulae of the drevogenins A, B, P, and D from Dregea volubilis are deduced from chemical and physical properties of these substances as well as of their derivatives. Drevogenin D most probably is 3β,11β,12β,14β,20ζ‐pentahydroxy‐Δ5‐pregnene 1. Drevogenin P 11 is the corresponding 20‐oxo compound, the drevogenins B 17 and A 19 are the 12‐O‐acetyl and the 12‐O‐acetyl‐11‐O‐isovaleryl derivatives, respectively, of drevogenin P.

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A total of fifteen substances were identified through thin‐layer chromatography, after mild acid hydrolysis of the chloroform extract from the seeds of Dregea volubilis (L.) BENTH. ex HOOK. Of these fifteen substances, eight (B, D, P, O; U, V, H and T) were isolated in crystalline form. Two of these were identical with the known genins drevogenin B (B) and drevogenin D (D). Drevogenin P (P) and the unknown substance O (probably a genin) were isolated for the first time. U proved to be identical with D‐cymarose, V with the biose U1 obtained from Asclepias lilacina, and H with (+)‐methyl‐pachybioside. T was not investigated (probably a sugar derivative).

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