New Triterpenoid Glycosides fromCentella asiatica

Four new triterpenoid glycosides named asiaticoside C (1), D (2), E (3), and F (4) were isolated from the BuOH fraction of the EtOH extract of whole plants of Centella asiatica, together with three known compounds, asiaticoside (5), madecassoside (6), and scheffuroside B (7). Based on FAB-MS, IR, 1H- and 13C-NMR, and 2D-NMR data (HMQC, HMBC, COSY), the structures of the new compounds were determined as (2α,3β,4α)-23-(acetyloxy)-2,3-dihydroxyurs-12-en-28-oic acid O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (1), (2α,3β)-2,3-dihydroxyurs-12-en-28-oic acid O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (2), asiatic acid 6-O-β-D-glycopyranosyl-β-D-glucopyranosyl ester (3), (3β,4α)-3,23-dihydroxyurs-12-en-28-oic acid O-α-L-rhamnopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (4).