Cytotoxic ent-Abietane-type diterpenoids from the roots of Euphorbia ebracteolata.

Euphoroids A-C (1-3), three new ent-abietane-type diterpenoids, together with ten known analogues (4-13) were obtained from the roots of Euphorbia ebracteolata. The structures of these compounds were determined by extensive spectroscopic data analysis, including UV, HRESIMS, 1D-, and 2D-NMR data. The inhibitory effects of compounds 1-13 on human cancer cells were determined using the MTT assay. The results revealed that new compounds 2 and 3 showed moderate cytotoxic activities against human cancer cell lines. Especially, compound 3 displayed selective cytotoxic effect agains cancer cell lines.