Discovery of a series of 1,3,4-oxadiazole-2(3H)-thione derivatives containing piperazine skeleton as potential FAK inhibitors

Abstract Focal adhesion kinase (FAK) is an important drug target that plays a fundamental role in mediating signal transduction system. We report herein the discovery of a novel class of 1,3,4-oxadiazole-2(3 H )-thione derivatives containing piperazine skeleton with improved potency toward FAK. All of the 17 new synthesized compounds were assayed for the anticancer activities against four cancer cells, HepG2, Hela, SW116 and BGC823. Because of the combination of 1,4-benzodioxan, 1,3,4-oxadiazole and piperazine ring, most of them exhibited remarkable antitumor activities. Notably, compound 5m showed the most potent biological activities (IC 50  = 5.78 μM for HepG2, and IC 50  = 47.15 μM for SW1116), and its anti-FAK inhibitory activity (IC 50  = 0.78 μM) was also the best. Computational docking studies also showed that compound 5m has interaction with FAK key residues in the active site.