Design, synthesis, and biological evaluation of a dichloro-substituted schiff base as an α-amylase inhibitor:...

Diabetes mellitus (DM) is a chronic metabolic condition characterized by persistently high blood glucose levels. The emergence of drug resistance in DM therapy presents significant clinical challenges, highlighting the need for the development of new and effective therapeutic agents. The primary objective of this study is to investigate the potential anti-diabetic activity of a newly designed Schiff base molecule, 2-[(2,4-dichloro-benzylidene)-amino]-4-methyl-phenol [compound (I)]. Compound (I) was synthesized, and its structure was confirmed using spectroscopic methods such as UV-Vis, FT-IR, and NMR spectroscopy. Single-crystal X-ray diffraction (SC-XRD) revealed that compound (I) crystallizes in the orthorhombic P2₁2₁2₁ space group and is stabilized by a combination of intra- and intermolecular hydrogen bonds (O-H···N, O-H···O, C-H···O, and C-H···Cl), forming a robust 3D supramolecular framework. The compound (I) was evaluated for its anti-diabetic potential using In-silico α-amylase inhibition assays. The compound's cytocompatibility was assessed using the MTT assay. The interaction pattern and binding orientation of compound (I) within the catalytic site of human pancreatic α-amylase (HPA) was explored through molecular docking studies, supporting the biological results. Furthermore, the stability of the docked complex was evaluated through 100 ns molecular dynamics (MD) simulations. In addition, the quantum computational analysis was investigated using Density Functional Theory (DFT) at the B3LYP/6-31++G(d,p) level were conducted to explore the electronic properties of compound (I), including electrophilicity, nucleophilicity, hardness, and softness. Moreover, the binding thermodynamics of compound (I) with α-amylase were examined by Isothermal Titration Calorimetry (ITC), which elucidated the thermodynamic parameters and interaction mechanisms.