A new flavonoid, (2'''E,6'''S)-4''-(6-hydroxy-2,6-dimethylocta-2,7-dienoyl)-vitexin (1), and five known compounds (2-6) were isolated from the thorn of Gleditsia sinensis Lam. Their structures were determined by comprehensive and comparative spectroscopic analysis of NMR and MS data. The absolute configuration of the new compound was deduced by analysis of the experimental and calculated 13C NMR data. The protective effects against lipopolysaccharide (LPS)-induced apoptosis in normal rat kidney tubule epithelioid (NRK 52e) cells of the isolated compounds were investigated in vitro, whose results showed that compound 1 showed significant protective effect with the EC50 value of 3.0 μM.
Keywords: Fabaceae; Gleditsia sinensis Lam.; flavonoids; renoprotective effect.