Dios polysapon in a, a new polyoxygenated spiro-stanol saponin from the tubers of dioscorea polygonoides

摘要

Chemical investigation of the tubers of Dioscorea polygonoides has resulted in the isolation of a novel polyoxygenated spirostanol saponin, named diospolysaponin A (1), along with a known spirostanol saponin (2). The structure of 1 was determined on the basis of spectroscopic analysis and by enzymatic hydrolysis followed by chromatographic and spectroscopic studies to be (23S,25R)-12alpha, 14alpha, 17alpha,23-tetrahydroxyspirost-5-en-3beta-yl O-alpha-L-rhamnopyranosyl-(l->2)-beta-D-glucopyranoside. The cytotoxic activity of 1 and 2 and their aglycons against HSC-2 cells is briefly presented.