essential for the antidiabeticactivity of flavonoids, we synthesized two series of flavonoids, 5,7‐dihydroxyflavanones and 5,7‐dihydroxyflavones. In a screening for potential antidiabeticactivity, most of the flavonoids showed a remarkable in vitro activity, and compounds 1f, 2d, and 3c were significantly more effective than the positive control, metformin. The biological activity was mainly affected