Cytotoxic spirostane-type saponins from the roots of Chlorophytum borivilianum.

Four new spirostane-type saponins named borivilianosides E-H (1-4) were isolated from an ethanol extract of the roots of Chlorophytum borivilianum together with two known steroid saponins (5 and 6). The structures of 1-4 were elucidated using mainly 2D NMR spectroscopic techniques and mass spectrometry. The cytotoxicity of borivilianosides F (2), G (3), and H (4) and three known compounds was evaluated using two human colon cancer cell lines (HT-29 and HCT 116).