[Studies on antibacterial constituents of Discocleidion rufescens (2)].

To screen effective constituents of Discocleidion rufescens against bacteria. Compounds were isolated by bioassay-guided fractionation method with various chromatographic methods and their structures were determined by spectral analysis and chemical evidence. Seven compounds were isolated from the Et2O and n-BuOH extracts and identified as 5,7-dihydroxy-4'-methoxy flavone (1), quercetin (2), apigenin-7-O-beta-D-glucopyranoside (3), apigenin-7-O-neohesperidoside (4), luteolin-7-O-neohesperidoside (5), gallic acid (6) and beta-daucosteol (7). Compounds 1-6 were isolated from genus Discocleidion for the first time and exhibited certain inhibitory activity against Escherichia coli. Compound 6 also showed antibacterial activity against Staphylococus aureus.