Isolation and Structural Identification of Lignans from Dregea sinensis Hemsl

In order to study the chemical constituents of Dregea sinensis Hemsl, five lignans were isolated from the roots of Dregea sinensis Hemsl by AB-8 macroporous resin column, silica gel column, Sephadex LH-20 column and semi-preparative HPLC. On the basis of 1D and 2D NMR data and MS analyses, their structures were identified as 4',4"-dihydroxy-3,3',3",5,5',5"-hexamethoxy-7,9':7',9-diepoxy-4,8"-oxy-8,8'-sesquineolignan-7",9"-diol (1), 4',4"-dihydroxy-3,3',3",5,5'-pentamethoxy-7,9':7',9-diepoxy-4,8"-oxy-8,8'-sesquineo-lignan-7",9"-diol (2), (+)-isolariciresinol (3), erythro-guaiacylycerol-β-O-4'-coniferyl alcohol (4), diasyringaresinol (5). These compounds were isolated from this plant for the first time.