Triterpenoid saponins from the roots of Clematis uncinata.

Eight new bisdesmosidic triterpenoid saponins, clematiunicinosides A-H (1-8), along with eleven known ones (9-19), were isolated from the roots of Clematis uncinata. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. All the isolated saponins were tested for their cytotoxic activities on human caski cervical cancer (Caski) cells, and compounds 13, 17 and 19 exhibited inhibitory effect on Caski cells.