New lignans from the roots of Valeriana prionophylla with Antioxidative and Vasorelaxant Activities

Two new 7,9’:7’,9-diepoxylignan glycosides have been isolated from the roots of Valeriana Pprionophylla Standl. Their structures have been established on the basis of 1D and 2D NMR experiments as prinsepiol-4-O--D-glucoside (1) and fraxiresinol-4’-O--D-glucoside (2). In addition, 8-hydroxypinoresinol-4’-O--D-glucoside (3), 8-hydroxypinoresinol (4), prinsepiol (5), wich have already been isolated from the roots of V. Officinalis, and chlorogenic acid were isolated and characterized. Compounds 1, 3, 4 and 5 were evaluated for its antioxidative properties in Trolox equivalent antioxidant activity (TEAC) and chemiluminescence (CL) assay. More over, the same compounds for the vascular activity in rat aorta rings were tested by using an in vitro model. The aglycones 4 e 5 were found to have powerful antioxidant activity; in addition aglycone 4 has shown an higher vasorelaxant activity compared to the others one.