Flavonoids from the bran of Avena sativa

AIM: To investigate the chemical constituents from the bran of Avena sativa. METHODS: Compounds were isolated and purified by various column chromatographic techniques using macroporous resin, silica gel, Sephadex LH-20, ODS, and preparative reversed-phase HPLC. Their structures were elucidated by physicochemical properties and spectroscopic data. RESULTS: Fifteen chemical constituents were isolated and identified as kaempferol 3-O-(2, 3-di-E-p-coumaroyl)--L-rhamnopyranoside (1), kaempferol 3-O-(3-E-p-coumaroyl)--L-rhamnopyranoside (2), kaempferol 3-O-(2-O-E-p-coumaroyl)--D-glucopyranoside (3), kaempferol 3-O--D-glucopyranoside (4), kaempferol 7-O--L-rhamnopyranoside (5), linarin (6), tilianin (7), myricitrin (8), quercitrin (9), kaempferol 3-O-rutinoside (10), rutin (12), tricin 7-O--D-glucopyranoside (12), tricin (13), kaempferol (14), and luteolin (15). CONCLUSION: Compounds 1-9 were isolated from Avena sativa Linn. for the first time.