NEOLIGNANS FROM PIPER KADSURA(Ⅱ)

摘要

Two new bicyclo[3,2,1]octanoid neolignans,named as kadsurenin I andkadsurenin J were isolated from Piper kadsura(Choiey)Ohwi.Based on the spectros-copic analysis(UV,IR,MS and NMR)and chemical derivatization,their structures wereestablished as 7R,8R,1’R,2’S,3’R-Δ~s’-3,4,5’-trimethoxy-2’-hydroxy-1’,2’,3’,4’-tetrahydro-4’-oxo-7.3’,8.1’-neolignan and 7R,8R,1’R,2’S,3’R-Δ~s’-3,4,5’-trimethoxy-2’-acetoxy-1’,2’,3’,4’-tetrabydro-4’-oxo-7.3’,8.1’-neolignan respectively.