A new lupane triterpene from Tetracera scandens L., xanthine oxidase inhibitor

From the MeOH extract of the stem of Tetracera scandens L., a new nor-lupane triterpene, 28-O-beta-D-glucopyranosyl ester of platanic acid (1), has been isolated together with six known compounds. Their structures were elucidated on the basis of spectroscopic data. Compounds 16 displayed significant xanthine oxidase inhibitory activity in a concentration-dependent manner, and compound 4 showed more potent inhibitory activity with an IC50 value of 1.9?mu M than that of a positive control allopurinol (IC50 2.5?mu M).