Design, synthesis, and pharmacological evaluation of 4-azolyl-benzamide derivatives as novel GPR52 agonists

G protein-coupled receptor 52 (GPR52) agonists are expected to improve the symptoms of psychiatric disorders. During exploration for a novel class of GPR52 agonists with good pharmacokinetic profiles, we synthesized 4-(3-(3-fluoro-5-(trifluoromethyl)benzy1)-5-methyl-1H-1,2,4-triazol-1-y1)-2-methylbenzamide (4u; half maximal effective concentration (EC50) = 75 nM, maximal response (E-max) = 122%) starting from a high-throughput screening hit 3 (EC50 = 470 nM, E-max = 56%). The structural features of a reported GPR52 agonist were applied to 3, led to design 4-azolylbenzamides as novel GPR52 agonists. A structure-activity relationship study of 4-azolylbenzamide resulted in the design of the 1,2,4-triazole derivative 4u, which demonstrated excellent bioavailability in rats (F = 53.8%). Oral administration of 4u (10 mg/kg) significantly suppressed methamphetamine-induced hyperlocomotion in mice. Thus, 4u is a promising lead compound for drug discovery research of GPR52 agonists. (C) 2017 Elsevier Ltd. All rights reserved.