New triterpenoid saponins with cytotoxic activities from Ligularia przewalskii

Two new triterpenoid saponins, a cycloartane-type triterpenoid saponin (1) and a oleanane-type triterpenoid saponin (2), were isolated from the whole plant of Ligularia przewalskii. Their structures were elucidated based on extensive spectroscopic studies, including IR, UV, HR-ESI-MS, 1D and 2D NMR experiments. (H-1-NMR, C-13-NMR, DEPT, H-1-H-1 COSY, HMBC, HSQC, and NOESY). Their cytotoxic activities were evaluated against six human cancer (HeLa, HepG2, SGC7901, MDA231, HL60, and Lewis) cell lines in vitro using MTT assay. As a result, two triterpenoid saponins showed potent cytotoxic activities against six tumors cell lines and with broad spectrum activities against six human cancer, with IC50 values from 8.40 to 24.39 mu M. The cytotoxic activities of 2 are more potent.