4,4'-Dihydroxy-3,3',9-trimethoxy-9,9'-epoxylignan
4,4'-Dihydroxy-3,3',9-trimethoxy-9,9'epoxylignan is a natural product isolated and purified from the herbs of Viburnum foetidum, showing cytotoxic activities against four tumor cell lines (A549, SK-OV-3, SKMEL-2 and HCT15).