Nepalensinols D—G, New Resveratrol Oligomers from Kobresia nepalensis (Cyperaceae) as Potent Inhibitors of DNA Topoisomerase II

Four new resveratrol oligomers, nepalensinols D—G, were isolated from the stem of Kobresia nepalensis (Cyperaceae). The structures were determined by detailed NMR spectral analysis. The compounds were assessed for their inhibitory activity against human topoisomerase II, a potential target of anti-tumor agents. These stilbenoids showed potent inhibitory activity against human topoisomerase II with IC50 values of 5—15 μM.