Abstract
Xanthine oxidase (XO) inhibitors were isolated from the flowers and buds of Daphne genkwa SIEB. et ZUCC. (Thymelaeaceae) and were identified as genkwanin (1), apigenin (2), luteolin 7-methyl ether (3) and luteolin (4). Compounds 2 and 4 showed particularly strong inhibitory activity against XO. The modes of inhibition by 2 and 4 with respect to xanthine as a substrate were of mixed type. This is the first report of isolation of 3 and 4 from these flowers and buds.