New dibenzocyclooctadiene lignan from Schisandra chinensis (Turcz.) Baill. fruits

Repeated column chromatography using Sephadex LH-20, silica gel (SiO2), and octadecyl SiO2 (ODS) as well as preparative HPLC column chromatography led to isolation of a new dibenzocyclooctadiene lignan along with four known ones, gomisin L2 (1), L1 (2), M1 (3), and M2 (4). Their chemical structures were fixed based on MS, IR, and NMR data analyses. In addition, the stereochemistry of atropisomers, the absolute configuration of the axial chirality in a biphenyl structure, was confirmed by a CD experiment. The new lignan was named gomisin M3 (5).