Stilbenoids of Kobresia nepalensis (Cyperaceae) exhibiting DNA topoisomerase II inhibition

Resveratrol oligomers, nepalensinols A, B and C, were isolated as potent inhibitors of topoisomerase II, and are more potent than the anti-cancer drug, etoposide. Nepalensinol B is the most potent, with an IC50 of 0.02 μg/ml.