To discover novel α-glucosidase inhibitors, a series of coumarin- thiazolidine-2,4‑dione hybrids (BJX1∼20) were synthesized and assessed their inhibitory activities against α-glucosidase. Compared to acarbose (IC50 = 655.01 ± 52.54 μM), coumarin-thiazolidinedione hybrids (BJX1∼20) displayed stronger α-glucosidase inhibitory activity, with IC50 values ranging from 5.12 ± 0.48 to 24.07 ± 1.96 μM. BJX3, BJX9, and BJX15 exhibited strongest inhibitory activities against α-glucosidase and acted as non-competitive inhibitors. The fluorescence quenching experiment revealed that the interaction between BJX3, BJX9, BJX15, and α-glucosidase followed a static binding process. CD spectra and 3D fluorescence spectra analysis revealed that the binding of BJX3, BJX9, and BJX15 to α-glucosidase induced a conformation change of α-glucosidase, thereby inhibiting its activity. Molecular docking simulation revealed the binding mechanism of BJX3, BJX9, and BJX15 with α-glucosidase. In vitro cytotoxicity assay indicated BJX15 (0∼64 μM) showed no obvious cytotoxicity against HEK 293 cells. In vivo experiments in mice demonstrated the ameliorative effect of orally administered BJX15 (50 mg kg-1) on postprandial hyperglycemia.
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