Synthesis of Bis-indolylmethane sulfonohydrazides derivatives as potent α-Glucosidase inhibitors

In search of better alpha-glucosidase inhibitors, a series of bis-indolylmethane sulfonohydrazides derivatives (1-14) were synthesized and evaluated for their alpha-glucosidase inhibitory potential. All derivatives exhibited outstanding alpha-glucosidase inhibition with IC50 values ranging between 0.10 +/- 0.05 to 5.1 +/- 0.05 mu M when compared with standard drug acarbose having IC50 value 856.28 +/- 3.15 mu M. Among the series, analog 7 (0.10 +/- 0.05 mu M) with tri-chloro substitution on phenyl ring was identified as the most potent inhibitor of alpha-glucosidase ( similar to 8500 times). The structure activity relationship has been also established. Molecular docking studies were also performed to help understand the binding interaction of the most active analogs with receptors. From the docking studies, it was observed that all the active bis-indolylmethane sulfonohydrazides derivatives showed considerable binding interactions within the active site (acarbose inhibition site) of alpha-glucosidase. We also evaluated toxicity of all derivatives and found none of them are toxic.