apigetrin and vitexin

To study the chemical constituents from Hibiscus syriacus leaves and their α-glucosidase inhibitory activities.. Column chromatography including macroporous resins, silica gel and Sephadex LH-20 were used for the isolation and purification of all compounds. Spectroscopic methods including physical and chemical properties, 1H-NMR and 13C-NMR were used for the identification of structures. Their α-glucosidase inhibitory activities were detected by a 96-well microplate.. 15 compounds were isolated and identified as β-sitosterol(1), β-daucostero (2), β-amyrin (3), oleanolic acid (4), stigmast-4-en-3-one (5), friedelin (6), syriacusin A (7), kaempferol (8), isovitexin (9), vitexin (10), apigenin (11), apigenin-7-O-β-D-glucopyranoside (12), luteolin-7-O-β-D-glucopyranoside (13), vitexin-7-O-β-D-glucopyranoside (14) and rutin (15).. All the compounds are isolated from the leaves of Hibiscus syriacus for the first time. Taking acarbose as positive control, the α-glucosidase inhibitory activities of 15 compounds were evaluated. Compounds 7 and 9 have shown strong α-glucosidase inhibitory activities with IC50 of 39.03 ± 0.38 and 32.12 ± 0.62 mg/L, inhibition ratio of 94.95% and 97.15%, respectively.

Topics: alpha-Glucosidases; Apigenin; Glucosides; Glycoside Hydrolase Inhibitors; Hibiscus; Kaempferols; Luteolin; Oleanolic Acid; Phytochemicals; Plant Leaves; Sitosterols; Stigmasterol; Triterpenes

To separate and identify the chemical constituents from the leaves of Broussonetia papyrifera (Linn.) Vent, various columns including Diaion HP-20, Toyopearl HW-40C, Sephadex LH-20, silica gel were employed for the isolation and purification of compounds from the leaves of B. papyrifera. The structures of the compounds were elucidated by their physiochemical characteristics and spectral data. Nineteen compounds were isolated from the leaves of B. papyrifera and their structures were identified as apigenin (1), apigenin-7-O-beta-D-glucopyranoside (2), chrysoerid-7-O-beta-D-glucopyranoside (3), apigenin-7-O-beta-D-glucopyranuronide (4), vitexin-7-O-beta-D-glucopyranoside (5), luteolin (6), 5,7,4'-trihydroxyl-6-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (7), 5,7,4'-trihydroxyl-8-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (8), saponaretin (9), vitexin (10), benzyl benzoate-2, 6-di-O-beta-D-glucopyranoside (11), (2R, 3R, 5R, 6S, 9R)-3-hydroxy-5,6-epoxy-beta-ionol-2-O-beta-D-glucopyranoside (12), (2R, 3R, 5R, 6S, 9R)-3-hydroxyl-5,6-epoxy-acetyl-beta-ionol-2-O-beta-D-glucopyranoside (13), ficustriol (14), (6S, 9S)-roseoside (15), 3beta-hydroxy-5alpha,6alpha-epoxy-beta-ionone-2alpha-O-beta-D-glucopyranoside (16), icariside B1 (17), sammangaoside A (18), 3-hydroxy-5alpha,6alpha-epoxy-beta-ionone (19). Compounds 11, 12 and 13 are new compounds, the others are isolated from this genus Broussonetia for the first time.

Topics: Apigenin; Broussonetia; Glucosides; Luteolin; Molecular Structure; Plant Leaves; Plants, Medicinal