The Constituents of Schizandra chinensis Baill. X. The Structures of .GAMMA.-schizandrin and four new lignans,(-)-gomisins L1 and L2,(.+-.)-gomisin M1 and (+)-gomisin M2.

Four new dibenzocyclooctadiene lignans, named (-)-gomisins L1 (6) and L3 (7), (±)-gomisin M1 (8) and (+)-gomisin M2 (9), were isolated from the fruits of Schizandra chinensis BAILL. (Schizandraceae). Their absolute structures were elucidated by means of chemical and spectral studies. The stereostructure of γ-schizandrin (1, dl-form), the plane structure of which had already been suggested by Kochetkov et al. and Liu et al., was also elucidated on the basis of chemical and spectral studies.