Abstract.

No abstract

A series of 2-(N-cyclicamino)chromone derivatives (1a-4c) and 3-(N-cyclicamino)chromone derivatives (5a-8c) were synthesized, and their monoamine oxidase (MAO) A and B inhibitory activities were studied as part of a structure-activity relationship investigation. Compounds 1a-4c showed no remarkable inhibition for MAO-A or MAO-B, whereas compounds 5a-8c (with a few exceptions) showed significant and selective inhibition of MAO-B. Of these compounds, 7c, 7-methoxy-3-(4-phenyl-1-piperazinyl)-4H-1-benzopyran-4-one inhibited MAO-B the most potently and selectively, having IC 50 of 15 nM and an MAO-B selectivity index of more than 6700; c.f, 50 nM and 2000, respectively, for safinamide. The mode of inhibition of 7c to MAO-B was competitive and reversible. Considering the IC 50 values and selectivity indices of the other synthetic compounds, the presence of the methoxy group on the chromone ring (R 2 ) of 7c seemed to increase MAO-B inhibition. Molecular docking analysis also supports this hypothesis. Our results suggest that 3-(N-cyclicamino)chromones are useful lead compounds for the development of MAO-B inhibitors.