New prenylated flavonoid glycosides from the stems of Celastrus orbiculatus with their anti-tumor activities

Two new prenylated flavonoid glycosides (1-2), together with five known compounds (3-7) were isolated from the EtOAc-soluble extract of the stems of Celastrus orbiculatus. The structures of new compounds were elucidated with spectroscopic and physico-chemical analyses. All isolates were evaluated for in vitro cytotoxic activities against HepG2, MCF-7, A549, and A2780 cancer cells. Among them, compound 1 showed potential antiproliferative activity on A2780 cells with IC50 value of 10.76 μM. In addition, compound 2 exhibited selective cytotoxic activity on A2780 cells with IC50 value of 26.30 μM.