Abstract
Five triterpenoid saponins were isolated from Anemone flaccida Fr. Schmidt. Their structures were identified as glycoside St-I4a (1), glycoside St-J (2), anhuienoside E (3), hederasaponin B (4), and flaccidoside II (5). Compounds 1–2 were isolated from Anemone family for the first time, and compounds 3–4 were isolated from this plant for the first time. The inhibitory effects of saponins on proliferation of HeLa cells were studied by MTT assay, the apoptosis-induction activity was observed by cell-cycle analysis and caspase-3 expression assay. The antitumor activities of the saponins were ranked in the following order: 5>3>4>1>2. The data presented here indicated that naturally occurring triterpenoid saponins can be regarded as excellent structures for the potential development of new anticancer agents.
Acknowledgements
We are grateful to Dr Xiao Yuan, Wuhan Botany Garden of Chinese Academy of Sciences for recording the ESI-MSn spectra. We also thank Prof. Guoqiang Song, Shanghai Institute of Materia Medica of Chinese Academy of Sciences for measuring the NMR spectra.