Steroidal saponins with cytotoxic activity from the stems and leaves of Paris fargesii

Paris fargesii is an important medicinal resource of the genus Paris. With the aim of developing, utilizing, and protecting the resources of P. fargesii rationally, we carried out a phytochemical investigation on the regenerative resources (stems and leaves) of this plant. Ultimately, eleven new spirostane saponins, parisfargosides SL-1-SL-11 (1-11), along with 6 known compounds (12-17) were isolated from the stems and leaves of P. fargesii for the first time. Their structures were elucidated on the basis of HR-ESI-MS, and 1D- and 2D-NMR data as well as chemical methods. The structures of compounds 1-6 contain one or two hydroxyl groups on the F ring, while compound 7 possesses a rare alpha, beta-unsaturated ketone unit on the B ring. Saponins 13, 14, and 16 displayed significant cytotoxicities against three human cancer lines (HepG2, A-549, and HCT116) with IC50 values ranging from 2.90 to 10.12 mu M.