Synthesis, Enzyme Inhibition, and in Silico Studies of Amino Acid Schiff Bases

Abstract

In this research, novel complexes of Zn(II) were produced using amino acid Schiff bases. First, new Schiff bases were synthesized from the reaction of 3-methoxy-2-hydroxybenzaldehyde (o-vanillin) and amino acid methyl esters (isoleucine, phenylalanine, methionine). The synthesis of new complexes was carried out by the reaction of these Schiff bases and Zn(OAc)(2).2H(2)O. The structures of the synthesized complexes were elucidated using elemental analysis, FT-IR, NMR, UV-vis spectroscopy, and thermal analysis techniques. In this research, we synthesized new complexes of Zn(II) with amino acid Schiff bases labeled as 1a-1c. We then examined their impact on specific metabolic enzymes, namely acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The results showed that the molecules exhibited potent inhibitory activities against all targets compared to the standard inhibitor as indicated by IC50 values. Ki values of the compounds for AChE and BChE enzymes were obtained in the range of 78.04 +/- 8.66-111.24 +/- 12.61 and 24.31 +/- 3.98-85.18 +/- 7.05 mu M, respectively. Molecular docking calculations were performed to investigate the biological activities of the metal complexes. The Protein Ligand Interaction Profiler (PLIP) was used to study the chemical interactions of metal complexes with enzymes.