Synthesis, Spectroscopic, Conceptual DFT Characterization and Molecular Docking Studies of Two Versatile di-Bromobenzaldehyde Derived Compounds

Abstract

(E)-4,6-dibromo-2-[(2-chlorophenylimino)methyl]-3-methoxyphenol (I) and (E)-4,6-dibromo-2-[(2,5-difluorophenylimino)methyl]-3-methoxyphenol (II) Schiff base compounds were synthesized and characterized by using experimental XRD, FT-IR, UV-Vis. spectroscopic methods and computational methods. Geometry optimizations were done by using Gaussian type orbitals in Gaussian 09 W and Slater type orbitals in ADF2009 software. Spectroscopic studies show that the compounds prefer enol form in both solid and solvent. Scan calculations revealed that the reason for the enol form preference and the energy for prototropic tautomerism. From the biological activity estimations, it was determined that the compounds could be a Monoamine Oxidase Type B inhibitor, and comparative in-silico molecular docking studies with reverse docking of human monoamine oxidase type B protein were performed. Theoretical NLO calculations show that the second-order polarizability values of I and II were over 18 and 13 times that of the urea. Conceptual DFT studies were carried out to determine the reactivity descriptors of the molecules.