Triterpene glycosides from the tubers of Anemone coronaria.

Six new triterpene glycosides (1-6), together with 11 known ones (7-17), have been isolated from a glycoside-enriched fraction prepared from the tubers of Anemone coronaria L. (Ranunculaceae). On the basis of extensive spectroscopic analysis, including 2D NMR data, and the results of hydrolytic cleavage, the structures of 1-6 were determined to be 3beta-[(O-beta-D-glucopyranosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-2beta,23-dihydroxyolean-12-en-28-oic acid (1), 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl-(1-->4)]-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid (2), 3beta-[(O-beta-D-glucopyranosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (3), 3beta-[(O-beta-D-glucopyranosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-2beta,23-dihydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (4), 3beta-[(O-beta-D-glucopyranosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-2beta-hydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (5), and 3beta-[(O-beta-D-glucopyranosyl-(1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-18-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (6), respectively. Furthermore, the isolated compounds were evaluated for their cytotoxic activity against HSC-2 cells.