New Pregnane Glycosides from Cynanchum ascyrifolium

Abstract

Two new pregnane glycosides, cynascyrosides D and E, were isolated from the roots of Cynanchum ascyrifolium. The structures of these compounds were determined on the basis of spectroscopic and chemical evidence as cynajapogenin A 3-O-α-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-L-cymaropyranoside and cynajapogenin A 3-O-β-D-glucopyranosyl-(1→4)-α-L-diginopyranosyl-(1→4)-β-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranoside.