A new flavone glycoside from Eriocaulon buergerianum

Ten compounds were isolated from the water extract of Eriocaulon buergerianum by HP20, ODS, Sephadex LH-20 and MCI Gel CHP-20 column chromatographic methods. Their structures were identified by spectroscopic and chemical approaches as 6-methoxyquercetin-3-O-(2'''-vanilloyl)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (1), syringaresinol-4'-O-β-D-glucopyranoside (2), rutin (3), 1-O-feruloylglycerol (4), 1,2-benzenediol (5), vomifoliol (6), β-D-(6-O-trans-feruloyl) fructofuranosyl-α-D-O-glucopyranosied (7), dihydroferulic acid (8), guanosine (9) and quercetin-3-O-β-gentiobioside (10). The compound 1 is a new compound, the compounds 2 and 4-10 were obtained from Eriocaulon genus for the first time, and the compound 3 was isolated from this plant for the first time. Molecular docking study showed that 1 is a potential inhibitor of TNF-α. The compound 1 was evaluated for their anti-inflammatory activities in vitro, and 1 showed significant inhibitory activity against TNF-α production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells at the concentrations of 1, 10 and 100 μmol·L^-1.