Structures of momordicines I, II and III, the bitter principles in the leaves and vines of Momordica charantia L.

Abstract

The bitter principles in the leaves and vines of Momordica charantia L. (Cucurbitaceae), momordicines I, C30H48O4·H2O, and II, C36H58O9, were isolated and their structures were elucidated as 3β, 7β, 23ζ-trihydroxy-cucurbita-5, 24-dien-19-al and its 23-O-β-glucopyranoside, respectively. The structure of momordicine III, which was isolated as its acetate, C48H68O16·1/2H2O, is indicated to be a 23-O-β-glucopyranoside of 3β, 7β, 23ζ-trihydroxy-24-oxo-cucurbita-5, 25-dien-19-al by the spectral and chemical evidence.