Exploring the molecular structure and in vitro biological potential of newly synthesized Fe(III), Co(II), and Ni(II) coordination compounds with 2-(pyridin-2-yl)-1H-benzimidazole and phenylalanine ligands

This study presents a thorough investigation into the synthesis, characterization, computational analysis, and biological evaluation of FePBZPHA, CoPBZPHA, and NiPBZPHA mixed-ligand complexes. They were synthesized in high yields via reactions between chloride salts of Iron, Cobalt, or Nickel with 2-(pyridin-2-yl)-1H-benzimidazole (PBZ) and Phenylalanine (PHA). They underwent extensive spectroscopic, elemental, conductivity, magnetic, and thermal analysis to confirm their formation. Molar conductivity measurements indicated their non-electrolytic nature, with UV-vis spectra revealing distinct absorption bands for PBZ and PHA ligands, shifting significantly upon metal ion coordination. Stoichiometry determination confirmed the 1:1:1 (M:PBZ: PHA) ratio, while FT -IR spectra comparison elucidated intricate binding modes, supported by mass spectra and elemental analysis. Thermal analysis revealed their thermal stability and decomposition pathways. DFT calculations unveiled octahedral coordination geometries and enhanced electron affinity, electronegativity, and reactivity of metal complexes. Biological evaluation showcased significantly enhanced efficacy of metal complexes in antimicrobial, anti-inflammatory, and antioxidant activities, with FePBZPHA exhibiting the highest potency. Molecular docking analysis highlighted their potential as therapeutic agents, with metal complexation enhancing binding affinity and interaction versatility. Overall, this study provides comprehensive insights into the synthesis, characterization, computational analysis, and biological evaluation of FePBZPHA, CoPBZPHA, and NiPBZPHA mixed-ligand complexes, suggesting promising applications in biomedicine and materials science.