Aryl-oxadiazole Schiff bases: Synthesis, α-glucosidase in vitro inhibitory activity and their in silico studies

Abstract

α-Glucosidase enzyme is a therapeutic target for diabetes mellitus and its inhibitors play a vital role in the treatment of this disease. A new series of aryl-oxadiazole Schiff bases (1–18) were synthesized and evaluated for α-glucosidase inhibitory potential. Fifteen compounds 1–8, 11–13, and 15–18 showed excellent inhibition with IC50 values ranging from 0.30 ± 0.2 to 35.1 ± 0.80 µM as compared to the standard inhibitor acarbose (IC50 = 38.45 ± 0.80 µM), nonetheless, the remaining compounds were found to have moderate activity. Among the series, compounds 7 (IC50 = 0.30 ± 0.2 μM) with hydroxy groups at phenyl rings on either side of the oxadiazole ring was identified as the most potent inhibitor of α-glucosidase. The molecular docking studies were conducted to understand the binding mode of active inhibitors with the active site of enzyme and results supported the experimental data. Keywords: Synthesis, Aryl-oxadiazole Schiff bases, α-glucosidase, Molecular docking, Structure-activity relationship (SAR)