Bidentatoside I, a New Triterpene Saponin from Achyranthes bidentata

Bidentatoside I (1) is a new triterpene saponin bearing an unusual dioxopropionic acid unit, isolated from the roots of Achyranthes bidentata. Structural elucidation was performed mainly by chemical and homo- and heteronuclear 2D NMR techniques. This compound did not show any potentiation of the in vitro cytotoxicity of cisplatin in the HT 29 human colon cancer cell line.