Cytotoxic constituents from Butea superba Roxb.

A carpin (3-hydroxy-9-methoxypterocarpan) (Medicarpin) (1) and four isoflavones, 7-hydroxy-4′-methoxy-isoflavone (Formononetin) (2); 7,4′-dimethoxyisoflavone (3); 5,4′-dihydroxy-7-methoxy-isoflavone (Prunetin) (4) and 7-hydroxy-6,4′-dimethoxyisoflavone (5) were isolated from the tuber roots of Butea superba Roxb. Compounds 2 and 4 showed moderate cytotoxic activity on KB cell lines with IC50 (μM) values of 37.3 ± 2.5 and 71.1 ± 0.8 and on BC cell lines with IC50 (μM) values of 32.7 ± 1.5 and 47.3 ± 0.3, respectively.