Discovery of N -(1-(3-fluorobenzoyl)-1 H -indol-5-yl)pyrazine-2-carboxamide: a novel, selective, and competitive indole-based lead inhibitor for human monoamine oxidase B

摘要

Herein, two new series of N-substituted indole-based analogues were rationally designed, synthesized via microwave heating technology, and evaluated as noteworthy MAO-B potential inhibitors. Compared to the reported indazole-based hits VI and VII , compounds 4b and 4e exhibited higher inhibitory activities over MAO-B with ICsub50/sub values of 1.65 and 0.78?μM, respectively. When compared to the modest selectivity index of rasagiline ( II , a well-known MAO-B inhibitor, SI 50), both 4b and 4e also showed better selectivity indices (SI 60 and 120, respectively). A further kinetic evaluation of the most potent derivative ( 4e ) displayed a competitive mode of inhibition (inhibition constant (K subi/sub)/MAO-B?=?94.52?nM). Reasonable explanations of the elicited biological activities were presented via SAR study and molecular docking simulation. Accordingly, the remarkable MAO-B inhibitory activity of 4e (N-(1-(3-fluorobenzoyl)-1H-indol-5-yl)pyrazine-2-carboxamide), with its selectivity and competitive inhibition, advocates its potential role as a promising lead worthy of further optimization.