Synthesis, biological evaluation, and molecular modeling of (E)-2-aryl-5-styryl-1,3,4-oxadiazole derivatives as acetylcholine esterase inhibitors

A library of 2,5-disubstituted 1,3,4-oxadiazole derivatives of (E)-2-aryl-5-(3,4,5-trimethoxystyryl)-1,3,4-oxadiazoles 4(a-o) and (E)-2-aryl-5-(2-benzo[d][1,3]dioxol-5-yl)vinyl)-1,3,4-oxadiazoles 5(a-q) were synthesized and evaluated for their in vitro acetylcholinesterase (AChE) inhibitory activity. All the synthesized compounds exhibited moderate to good inhibitory activity toward the AChE enzyme. Among the oxadiazole derivatives examined, compounds 4a, 4g, 5c, and 5m (IC50 values of 24.89, 13.72, 37.65, and 19.63 mu M, respectively) were found to be promising inhibitors of AChE. Molecular protein-ligand docking studies were examined for these compounds using GOLD docking software and their binding conformations were determined and the simultaneous interactions mode was also established for the potent derivatives.