Flavonoids from the leaves of Epimedium Koreanum Nakai and their potential cytotoxic activities

AbstractPhytochemical studies on the leaves of Epimedium koreanum Nakai have resulted in the discovery of two new flavonol glycosides, koreanoside F (1) and koreanoside G (2), along with six known flavonoids. Their structures were elucidated on the basis of HRESIMS, UV, IR, 1 D NMR and 2 D NMR data. Absolute configurations of 1 and 2 was further determined by 13C-NMR spectra with gate decoupling (GD). All of the compounds were evaluated for cytotoxic activities by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay. The results indicated that compounds 3, 5, 6, 7 and 8 inhibited the proliferation of A549 and NCI-292 cells with IC50 values of 5.7–23.5 μM. Real-time monitoring in three kinds of lung cancer cells and a kind of human bronchial epithelial cells treated with compound 6 was also assessed.