Ni(II) mixed-ligand chelates based on 2-hydroxy-1-naphthaldehyde as antimicrobial agents: Synthesis, characterization, and molecular modeling

Mohamed Ismael, Abdel-Mawgoud M.Abdel-Mawgoud, Mostafa K.Rabia, AlyAbdou

Chemistry Department, Faculty of Science, Sohag University, Sohag 82524, Egypt.

Abstract

New Ni (II) ternary chelates; based on 2-hydroxy-1-naphthaldehyde Schiff-base ligand with various N-heterocyclic co-ligands, were synthesized and characterized. Structural analysis were performed to estimate the chelates stability based on the cis- and trans- orientation around the Ni(II)-center using density functional theory (DFT) calculations. Moreover, selected quantum chemical descriptors had been computed using frontier molecular orbitals to evaluate the reactivity based on the electronic structural analysis. Pharmaceutical potential of the subject molecules have been estimated by screening the most important drug-likeness parameters. In silico investigation revealed that the target compounds could be potential bioactive drug-like molecules. Mixed-ligand effect on antimicrobial activity was in-vitro screened against pathogenic bacteria; E. coli (G^-), and B. cereus (G⁺), as well as A. fumigatus fungi. Interestingly, presence of co-ligand in the ternary Ni (II) chelates led to higher enhancement in the antimicrobial behavior comparing with its binary one. Finally, both theoretical and experimental data were combined for generating a structure activity relationship (SAR) model that might be used for the developing of new metal chelates as antimicrobial agents.

Keywords: Ni(II) ternary chelates, Density functional theory (DFT), Drug-likeness parameters, In-vitro antimicrobial, Structure activity relationship (SAR).