The aim of this study was to isolate the chemical constituents of the aerial parts of Polygala tenuifolia Willd. and to determine their antioxidant activities. Ten flavonoids were isolated and purified by silica gel, ...The aim of this study was to isolate the chemical constituents of the aerial parts of Polygala tenuifolia Willd. and to determine their antioxidant activities. Ten flavonoids were isolated and purified by silica gel, Sephadex LH-20, and ODS column chromatography, and semi-preparative HPLC. Their structures were elucidated by spectroscopic analysis and identified as isorhamnetin-3-O-13-D-glucopyranoside (1), isorhamnetin-3-O-13-D-galactopyranoside (2), quercetin-3-O-13-o-glucopyranosyl (1--*2)-I^-D-galactopyranoside (3), quercetin-3-O-13-O-glucopyranosyl (1---~2)-13-D-glucopyranoside (4), linarin (5), quercetin-3-O- 13-D-glucopyranoside (6), 5,7-dihydroxy-8-methxoyflavone-7-O-13-o-glucuronoside (7), isorhamnetin (8), kaempferol (9) and quercetin (10). All these compounds were isolated from this plant for the first time, and compounds 1-5 and 7 were isolated from the genus of Polygala for the first time. The antioxidant activities of the isolated compounds were evaluated by DPPH free radical scavenging assay, and compounds 3, 4, 6, 8, 9 and 10 showed potent antioxidant activities.展开更多
基金New-Century Talent Program, Ministry of Education of China (Grant No.985-2-102-113)National Science Fund for Excellent Young Scholars (Grant No. 81222051)National Key Technology R&D Program "New Drug Innovation" of China (Grant No. 2012ZX09304-005, 2012ZX09301002-002)
文摘The aim of this study was to isolate the chemical constituents of the aerial parts of Polygala tenuifolia Willd. and to determine their antioxidant activities. Ten flavonoids were isolated and purified by silica gel, Sephadex LH-20, and ODS column chromatography, and semi-preparative HPLC. Their structures were elucidated by spectroscopic analysis and identified as isorhamnetin-3-O-13-D-glucopyranoside (1), isorhamnetin-3-O-13-D-galactopyranoside (2), quercetin-3-O-13-o-glucopyranosyl (1--*2)-I^-D-galactopyranoside (3), quercetin-3-O-13-O-glucopyranosyl (1---~2)-13-D-glucopyranoside (4), linarin (5), quercetin-3-O- 13-D-glucopyranoside (6), 5,7-dihydroxy-8-methxoyflavone-7-O-13-o-glucuronoside (7), isorhamnetin (8), kaempferol (9) and quercetin (10). All these compounds were isolated from this plant for the first time, and compounds 1-5 and 7 were isolated from the genus of Polygala for the first time. The antioxidant activities of the isolated compounds were evaluated by DPPH free radical scavenging assay, and compounds 3, 4, 6, 8, 9 and 10 showed potent antioxidant activities.