Synthesis of benzimidazole-linked-1,3,4-oxadiazole carboxamides as GSK-3β inhibitors with in vivo antidepressant activity

Recent findings of potential implications of glycogen synthase kinase-3 beta (GSK-3 beta) dysfunction in psychiatric disorders like depression, have increased focus for development of GSK-3 beta inhibitors with possible anti -depressant activity. Keeping this in view, we synthesized a series of benzimidazole-linked-1,3,4-oxadiazole carboxamides and evaluated them for in vitro GSK-3 beta inhibition. Active compounds were investigated for in vivo antidepressant activity in Wistar rats. Docking studies of active compounds have also been performed. Among nineteen compounds synthesized, compounds 7a, 7r, 7j, and 7d exhibited significant potency against GSK-3 beta in sub-micromolar range with IC50 values of 0.13 mu M, 0.14 mu M, 0.20 mu M, 0.22 mu M respectively and significantly reduced immobility time (antidepressant-like activity) in rats compared to control group. Docking study showed key interactions of these compounds with GSK-3 beta. These compounds may thus serve as valuable candidates for subsequent development of effective drugs against depression and related disorders. (C) 2018 Published by Elsevier Inc.