Synthesis, in vitro evaluation and molecular docking studies of novel coumarin-isatin derivatives as α-glucosidase inhibitors

This study synthesized a series of novel coumarin-isatin derivatives and evaluated them for alpha-glucosidase inhibitory activity. The majority of the screened compounds exhibited excellent inhibition activities with IC50 values of 2.56 +/- 0.08-268.79 +/- 3.04 mu m, when compared to acarbose. Among the newly derivatives, compound 5p was found to be the most active compound in the library of coumarin-isatin derivatives. Furthermore, enzyme kinetic studies showed that compound 5p is a non-competitive inhibitor with a K-i of 2.14 mu m. Molecular docking analysis revealed the existence of hydrophobic and hydrogen interactions between compound 5p and the active site of alpha-glucosidase. Our results indicate that coumarin-isatin derivatives as a new class of alpha-glucosidase inhibitors.