Novel Co(II), Cu(II) and Fe(II) Pentadentate Schiff base complexes: Synthesis, characterization, antimicrobial, antioxidant, and molecular docking studies

The compound H2L, which is a ligand with five coordinating atoms, consisting of three nitrogen atoms and two sulfur atoms (N3S2), was reacted with Fe(OAc)2, Cu(OAc)2.H2O, and Co(OAc)2 & sdot;4H2O to form the corresponding metal complexes ([FeL], [CuL], [CoL]). Many techniques, including NMR (for ligand), FT-IR, UV-Vis, elemental analysis, and molar conductivity, were used to characterize the synthesized compounds. According to the spectrum of data, complex molecule structures have a distorted triangular bipyramidal geometry with five coordination locations. The compounds that exhibit non-electrolyte behavior in solution do not possess any conductivity features. Evaluation was performed to determine the antioxidant activity of the synthesized compounds in comparison to the stable free radical DPPH. The ligand and its metal complexes were evaluated for antibacterial activity against several Gram-positive and Gram-negative bacteria, as well as a yeast strain. In comparison to the common antibiotic Amoxycillin/Clavulanic Acid (AMC-30), the Schiff base ligand (H2L) and its Cu (II) metal complex showed noticeably larger inhibitory zones against S. aureus. All the compounds showed a high negative binding affinity for S. aureus amino acid molecules when they were docked. The results indicated that the metal complexes, particularly the cobalt complex, exhibited a higher affinity for binding compared to the free ligand.