Synthesis, characterization, in vitro and in silico studies of bis-hydrazone complexes derived from terephthalic dihydrazide

Abstract

Bis-hydrazone of terephthalic dihydrazide was designed and synthesized using terephthalic dihydrazide and picolinaldehyde. Various bioactive benzoic acids such as benzoic acid, aspirin and salicylic acid were selected as a counter ion moiety for preparing bis-hydrazone complexes (BHCs). The prepared BHCs were well characterized using spectroscopic techniques like 1H NMR, 13C NMR and FT-IR. The BHCs showed very good in vitro antidiabetic activity in the α-amylase enzyme inhibitory method and moderate activity in the α-glucosidase inhibitory method. The molecular docking interactions of BHCs were performed against the human pancreatic α-amylase enzyme (1HNY.pdb) and homology model of α-glucosidase (3A4A.pdb) to prove the enzyme inhibitory activity. The BHCs showed very good binding energy, the complex BHB showed 5 numbers of hydrogen bonding interactions with amino acid residues of 1HNY.pdb and BHS showed 5 numbers of hydrogen bonding interactions with 3A4A.pdb. Further, the molecular orbital studies were performed using density functional theory calculations in order to support the docking study.