Cytotoxic triterpenoid saponins from the defatted seeds of Camellia oleifera Abel.

Five new oleanane-type triterpenoid saponins, oleiferasaponins D-D (1-5), were isolated from the defatted seeds of Camellia oleifera Abel. Their structures were elucidated by spectroscopic and chemical methods. The cytotoxic activities of compounds 1-5 were evaluated against five human tumor cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780). Compounds 1-2 exhibited cytotoxic activity against five human cancer cell lines, with IC values ranging from 3.31 to 10.23 μM. Compounds 3-5 showed moderate cytotoxic activities toward the tested cell lines.