[Chemical constituents of flowers from Polygonum orientale].

OBJECTIVE: To study the chemical constituents in the active portion from the flowers of Polygonum oriental. METHOD: Chromatographic techniques were employed for isolation and purification of the constituents and their structures were determined by spectral analysis and chemical evidence. RESULT: Nine compounds were obtained and identified as alphitonin (1), methyl 3, 4-dihydroxybenzoate (2), apocynin (3), kaempferol-3-O-beta-D-glucoside (4), 1,3,5-trihydroxybenzene (5), 3,3'-dimethoxyellagic-acid-4-O-beta-D-glucoside (6), kaempferol-3-O-alpha-L-rhamnoside (7), quercetin-3-O-alpha-L-rhamnoside (8), kaempferol (9). CONCLUSION: Compounds 2, 4, 5 were isolated from P. oriental for the first time and compounds 1, 3 were firstly obtained from the genus Polygonum.