Chemical constituents from the branches of Millettia brandisiana and their biological activities

The branches of Millettia brandisiana Kurz were investigated for the first time. A new isoflavone named bran-disianone H (1) and a new natural product isoflavone (4 '-O-methylelongatin, 2) together with thirteen known compounds were obtained. Compounds 3-10 were reported for the first time from this plant. Their chemical structures were established by spectroscopic analysis and comparison with previously published data. Compound 7 showed a stronger activity against a cholangiocarcinoma cell line (KKU-M156) (IC50 = 2.98 +/- 1.08 mu g/mL), than the control agent cisplatin (IC50 = 4.88 +/- 0.75 mu g/mL). Moreover, compounds 1- 3, 6, 7, 9 and 12 - 14 were cytotoxic toward the HepG2 and KKU-M156 cell lines, with IC50 values ranging from 4.76 to 29.71 mu g/mL.