New Benzimidazole‐Based Fe (III) and Cr (III) Complexes: Characterization, Bioactivity Screening, and Theoretical Implementations Using DFT and Molecular Docking Analysis

Abstract

Two new Fe (III) and Cr (III) complexes had been synthesized and structurally characterized. The new complexes were based on 2‐methyl‐benzimidazole (MB) and salicylic acid (H2L). Elemental analyses, Fourier transform infrared spectroscopy, UV‐–Vis, mass spectra, conductivity, magnetic, and thermal measurements were used to formulate the compounds structures. The results revealed octahedral geometry for both of Fe (III) and Cr (III) complexes. Structure elucidation of these complexes was also supported by density functional theory (DFT) along with optimized geometrical parameters. Natural bond orbital analysis and molecular electrostatic potential were also investigated. Electronic absorption spectra were theoretically performed using the time‐dependent TD‐DFT/B3LYP in gas phase and acetonitrtile as a solvent. Furthermore, the bio‐mimicking activity as antimicrobial and anti‐inflammatory activity of the understudy compounds was in vitro screened. The results showed that the Fe (III) and Cr (III) complexes exhibited higher pathogenic action than the free ligands. Molecular docking investigation against 3T88 (E. Coli) and 5IKT (Cyclooxygenase‐2) was carried out to provide deep insights into their role in inhibiting the growth of pathogenic microbes.