Isatin based thiosemicarbazide derivatives as potential inhibitor of α-glucosidase, synthesis and their molecular docking study

•Synthesis of Isatin bearing thiosemicarbazide analogs.•In vitro alpha glucosydase activity.•Identification of a new class of alpha glucosydase activity.•Structure activity relationship established.•Molecular docking. A new series of isatin based thiosemicarbazide derivatives 1–15 were synthesized and characterized by 1H NMR, 13C NMR and HR-EIMS. The synthetic derivatives were evaluated for α-glucosidase inhibitory potential. All compounds showed excellent α-glucosidase inhibitory potential having IC50 values ranging between 1.20 ± 0.10 to 35.60 ± 0.80 µM when compared with the standard acarbose having IC50 value 38.60 ± 0.20 µM. Compound 3, 4, 5, 9, 10, 12 and 15 having IC50 values 2.20 ± 0.10, 3.5 ± 0.10, 1.20 ± 0.10, 5.20 ± 0.20, 3.60 ± 0.10, 4.60 ± 0.20 and 3.90 ± 0.10 µM, respectively, was found many fold better than the standard acarbose having IC50 value 38.60 ± 0.20 µM. Structure activity relationship has been also established for all newly synthesized compounds, mainly based on substitution pattern on phenyl ring. Through molecular docking study the binding mode of active derivatives with α-glucosidase enzyme active site was confirmed. [Display omitted]