Synthesis of antihyperglycemic, α-glucosidase inhibitory, and DPPH free radical scavenging furanochalcones

A series of furanochalcone derivatives have been designed and synthesized. Molecular modeling studies were carried out to probe into the mechanism of binding of chalcone inhibitors and understand the structure-activity relationship to identify the contribution of scaffolds and groups in the synthesized analogs to biological activity. The three-dimensional model of alpha-glucosidase was constructed based on the crystal structure family 31 alpha-glycosidase (PDB 1XSI) using Modeller9v5. Docking of the inhibitors on the built homology model revealed interactions in the active site region mostly with Asp 252, Tyr254, Gln523, and Arg571. 2D-QSAR models were generated with CODESSA using Heuristic method. The best predictive model was generated using three descriptors that gave a correlation co-efficient (r (2)) 0.9886 and cross-validate (r (2)) 0.9338. The synthesized compounds were screened against the alpha-glucosidase inhibition and DPPH radical scavenging properties. All the synthetic compounds displayed varying degrees of alpha-glucosidase inhibitory and DPPH scavenging activities. Compound 8c was found most potent alpha-glucosidase inhibitor though; it could not display DPPH scavenging activity. When tested in vivo for antihyperglycemic activity in starch-loaded Wistar rats, 8c was equally effective in reducing time-dependent hyperglycemia as to the standard drug, Acarbose. Compound 8c may serve as an interesting compound for the development of therapeutics targeted against diet-induced hyperglycemia in diabetes.