Two new triterpenoid saponins from Gymnema sylvestre

Two new oleanane-type triterpenoid saponins, gymnemoside-W1 and W2, together with seven known compounds were isolated from the leaves of Gymnema sylvestre R. Br. By means of spectral and chemical analysis, the structures of the new compounds were elucidated as 16 β-hydroxyl olean-12-en-3-O-[β-D-glucopyranosyl (1→6)-β.D-glucopyranosyl]-28-O-β-D-glucopyranoside(1) and 16 β,21 β,28-trihydroxyl-olean-12-ene-3-O-glucoronopyranoside (2). The EtOHIH2O extracts of this plant were shown to be able to inhibit glucose absorption in rats.