Lignans from the root of Valeriana jatamansi and their biological evaluation

Investigation on the chemical components of Valeriana jatamansi Jones (Caprifoliaceae), a new lignan with pyran-ring, dipsalignan G (1), along with eight known compounds (2-9) were isolated. Their structures were elucidated by extensive analysis of 1D, 2D NMR and HR-ESI-MS spectroscopic data. Additionally, possible biosynthetic pathway of 1 was proposed. Finally, biological evaluation results showed that 8 had significant scavenging ability to ABTS and DPPH free radicals, with IC₅₀ values of 1.35 ± 0.01 and 2.94 ± 0.01 μg/ml, respectively.