Bioassay-guided isolation of lignanamides with potential anti-inflammatory effect from the roots of Solanum melongena L

Three new lignanamides, melongenamide E-G (1-3), together with fourteen known analogues (4-17) were isolated by bioassay-guided fractionation from the roots of Solanum melongena L. The chemical structures of all isolated compounds were elucidated using 1D and 2D NMR experiments and by comparing their spectroscopic and physical data with values from the published literature. These isolated compounds were tested for their inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in a macrophage cell line RAW 264.7. Compounds 1-7 and 10 showed moderate inhibition of NO production with IC50 values ranging from 10.6 +/- 2.3 to 33.7 +/- 2.7 mu M.