Strychnovanosides A-C, Three New Lignan Glycosides from Strychnos vanprukii

Phytochemical study of the methanolic extract of the stems and leaves of Strychnos vanprukii led to the isolation of three new (1-3) and four known (4-7) compounds. Their chemical structures were elucidated to be (+)-lyoniresinol 3 alpha-O-beta-D-allopyranoside (1), (-)-lyoniresinol 3 alpha-O-beta-D-allopyranoside (2), 2 alpha-[(3,5-dimethoxy-4-hydroxy)-benzoyl]-(-)-lyoniresinol-3 alpha-O-beta-D-glucopyranoside (3), (+)-lyoniresinol 3 alpha-O-beta-D-glucopyranoside (4), (-)-lyoniresinol 3 alpha-O-beta-D-glucopyranoside (5), palicoside (6), and rutin (7) by means of detailed HR-ESI-MS, 1D and 2D NMR spectroscopic analysis. In addition, the absolute configurations of 1-3 were determined by experimental Circular Dichroism (CD) spectra. This is the first report of compounds 5 and 7 from S. vanprukii. Compounds 1 - 7 showed inhibitory effects on NO production in LPS stimulated RAW 264.7 cells with IC50 values of 58.50 +/- 2.30, 67.70 +/- 2.23, 54.44 +/- 1.26, 71.58 +/- 3.59, 74.47 +/- 2.61, 83.62 +/- 2.25, and 47.57 +/- 4.01 mu M, respectively, compared to a value of 43.24 +/- 2.41 mu M for the positive control compound, N-G-monomethyl-L-arginine (L-NMMA).

Automated summary

This study isolated three new compounds and four known compounds from the stems and leaves of Strychnos vanprukii. The chemical structures were determined using various spectroscopic techniques. The compounds showed inhibitory effects on NO production in stimulated cells.