The structure and cytotoxic activity of a new saponin: cephoside A from Cephalaria elazigensis var. purpurea

Investigation of the aerial parts of Cephalaria elazigensis var. purpurea afforded one new oleanane-type saponin, namely cephoside A (1), and five known natural compounds (2-6). Compound 2, named anemoclemoside A, which is an unusual triterpene glycoside, was identified in the family Dipsacaceae for the first time. Chemical structures of all compounds were determined on the basis of the HRESIMS and 1D and 2D NMR data. Cephoside A (1) and anemoclemoside A (2) were assessed for their cytotoxic activities against HeLa cells, having IC50 values of 495 and 135 mu g/mL, respectively.