3-methylquercetin and quercitrin

To investigate the chemical constituents from Commelina communis, fifteen compounds were separated and purified by silica gel, Sephadex LH-20, and ODS column chromatography, and semi-preparative HPLC. By analyses of NMR and MS data as well as their physical and chemical properties, the structures of these compounds were identified as chrysoeriol-7-O-beta-D-glucoside( 1), methyl gallate(2), p-coumaric acid(3), protocatechuic acid(4), caffeic acid(5), p-hydroxybenzoic acid(6), 2-phenethyl-beta-D-gly-cosidase(7) , rhaponticin(8) , (7S, 8R) -dihydrodehydrodiconiferyl alcohol-9-O-beta-D-glucoside (9), isovitexin (10) , isofurcatain (11), isorhamnetin-3-O-beta-D-glucoside(12) , quercetin-3-O-alpha-L-rhamnoside (13) , isoquercitrin (14) , and 1, 2-dihydro-6, 8-dime-thoxy-7-1-(3, 5-dimethoxy-4-hydroxyphenyl) -N1, N2-bis-[2-( 4-hydroxyphenyl) ethyl] -2, 3-naphthalene dicarboxamide (15). Compounds 2, 5-9, 11, 13 were obtained from the genus Commelina for the first time.

Topics: Caffeic Acids; Chromatography, High Pressure Liquid; Commelina; Glucosides; Hydroxybenzoates; Quercetin

This paper describes a validated high-performance liquid chromatographic (HPLC) - photodiode array (PDA) detection method to quantitate five flavonol components as markers; rutin, quercitrin, quercetin, kaempferol and isorhamnetin for use in the quality control of Ginkgo biloba dosage forms.. Separation was achieved using a minibore Phenomenex Luna 5microm C(18) (2) column with dimensions 250 x 2.00mm at 45 degrees C with a one step linear gradient using acetonitrile:formic acid (0.3%) at a flow rate of 0.4ml/min.. The limits of quantitation for the flavonols were 2.76, 0.77, 1.11, 1.55 and 1.03microg/ml for rutin, quercitrin, quercetin, kaempferol and isorhamnetin, respectively. This method is linear over concentration ranges of 3-26microg/ml for all flavonols. Recoveries for rutin, quercitrin and kaempferol were above 94% while quercetin and isorhamnetin had average recoveries of 83% and 76%, respectively. Intraday precision did not exceed 6% and with-in day precision was better than 12% for all compounds.. A suitable method was developed to identify and quantitate five relevant flavonol marker compounds and was successfully used to assay some commercially available solid oral dosage forms of Ginkgo biloba .

Topics: Administration, Oral; Chromatography, High Pressure Liquid; Flavonols; Ginkgo biloba; Kaempferols; Plants, Medicinal; Quality Control; Quercetin; Rutin