Isolation and characterization of xanthine oxidase inhibitory constituents of Pyrenacantha staudtii / 药学学报

Six compounds have been isolated from the leaves of Pyrenacantha staudtii, two of which are new compounds. The new compounds have been characterized as kaempherol 3-O-beta-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside (1) and 4-beta-glucopyranosyl-(2-furyl)-5-methy-1,2-glucopyranoside phenylmethanone (2). The known compounds are 3-pyridinecarboxylic acid (3), beta-sitosterol (4), sitosterol 3-O-beta-glucopyranoside (5) and taraxerol (6). Their structures were determined by spectroscopic and chemical evidences. The two new compounds together with 3-pyridinecarboxylic acid showed significant in vitro xanthine oxidase inhibitory activity. To the best of our knowledge, this is the first report of these compounds from this plant.