In Silico and In Vitro Antimicrobial Evaluation of Iron(III) and Nickel(II) Schiff Base Complexes Bearing a Hydroxyethyl‐Substituted Ligand

ABSTRACT This research unveils a family of novel metal complex compounds featuring Fe(III) and Ni(II) ions elegantly coordinated to a hydroxyethyl‐substituted Schiff base ligand. The synthesized compounds were comprehensively characterized using elemental analysis, molar conductivity, infrared (IR) spectroscopy, UV–visible spectroscopy, magnetic moment measurements, mass spectrometry, and thermal analysis (TGA/DTG). These results confirmed the formation of stable, neutral complexes with octahedral geometries, Fe(III) adopting a low‐spin configuration (1.88 B.M.) and Ni(II) displaying a high‐spin state (2.70 B.M.). Job's method established a 1:2 metal‐to‐ligand stoichiometry. The biological potential of the prepared ligand and its complexes was evaluated through in vitro antimicrobial assays against a panel of Gram‐positive and Gram‐negative bacteria and several fungal strains. The metal complexes exhibited significantly enhanced antimicrobial activity compared to the free ligand, for instance, activity against E. coli increased from 40.00% for the free ligand to 88.00% for the complexes. In addition, molecular docking studies were performed to explore the binding interactions between the synthesized compounds and the E. coli FabH‐CoA enzyme (PDB ID: 1HNJ), supporting the experimental antimicrobial findings by revealing strong ligand–protein interactions and favorable binding energies. Overall, the integration of experimental characterization and computational modeling confirmed the successful synthesis, stability, and improved bioactivity of these Fe(III) and Ni(II) Schiff base complexes, underscoring their promise as potent antimicrobial candidates in the ongoing fight against drug‐resistant pathogens.