Hepatoprotective triterpenoid saponins from Callicarpa nudiflora

Four new triterpenoid saponins, 2α,3α,19α,24-tetrahydroxyolean-12-en-28-oic-acid 28-O-β-D-glucopyranosyl ester (1), 2α,3α,19α,23-tetrahydroxyolean-12-en-28-oic-acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-glu-copyranosyl ester (2), 2α,3α,19α-trihydroxyolean-12-en-28-oic-acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl ester (3), 2α,3α,23,29-tetrahydroxyurs-12,19-dien-28-oic-acid 28-O-β-D-glucopyranosyl ester (4), together with three known compounds (5-7), were isolated from the leaves of Callicarpa nudiflora HOOK. Their structures were established by means of spectroscopic methods and chemical evidence. Hepatoprotective activities of the isolated compounds against D-galactosamine-induced toxicity have been tested. Among them, compounds 1-3 showed pronounced hepatoprotective activities against D-galactosamine-induced toxicity in WB-F344 rat hepatic epithelial stem-like cells.