New isoflavones with cytotoxic activity from the rhizomes of Iris germanica L.

Two new compounds, 5-methoxy-3',4'-dihydroxy-6,7-methylenedioxy-4H-1-benzo-pyran-4-one(iriskashmirianin A) (1) and 5,3'-dihydroxy-3-(4'-β-D-glucopyranosyl)-6,7-methylenedioxy-4H-1-benzo-pyran-4-one (germanaism H) (2), along with eight known compounds (3-10), were isolated from the rhizomes of Iris germanica L. The cytotoxicities of these compounds were tested using Ehrlich's ascites carcinoma (EAC) cancer cell line by 3-(4, 5-dimethylthiazole-2-yl)-2, 5-diphenyltetrazoli-umbromide (MTT) and ATP assays. The results showed that these compounds possessed antiproliferative effects on EAC cell line. Among them, compound 1 possessed the best cytotoxic activity with IC50 ± SD of 20.9 ± 2.7 and 4.3 ± 0.9 μM for MTT and ATP assay methods, respectively.