Xanthine oxidase inhibitors from the flowers of Chrysanthemum sinense

Abstract

From the MeOH extract of the flowers of Chrysanthemum sinense, a new flavone glucoside, acacetin 7-O-(3-O-acetyl-β-D-glucopyranoside) (1), has been isolated together with 27 known compounds including flavonoids, caffeoylquinic acid derivatives, phenolics, and a monoterpenoid glucoside. Their structures were elucidated on the basis of spectroscopic data. Compounds 1-15, 20-24, and 27 displayed significant xanthine oxidase inhibitory activity in a concentration-dependent manner, and compounds 2-11 and 22 showed more potent inhibitory activity, with IC50 values ranging from 0.13 to 2.31 μM, than that of a positive control allopurinol (IC50 = 2.50 μM). The kinetic study indicated that 1-15 and 20-24 displayed competitive-type inhibition like that of allopurinol, while 27 displayed a mixed-type inhibition. © Georg Thieme Verlag KG Stuttgart.