Design, Characterization, and DFT exploration of new mononuclear Fe(III) and Co(II) complexes based on Isatin-hydrazone derivative: Anti-inflammatory profiling and molecular docking insights

Abstract

This research focuses on the synthesis and detailed analysis of novel compounds encompassing Fe(III) (C1) and Co(II) (C2) ions, featuring 4-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)hydrazono]methylphenyl 4-methylbenzenesulfonate ligand. The structural elucidation of these freshly prepared compounds was meticulously pursued employing a battery of spectroscopic techniques including NMR, UV–vis, IR, mass spectroscopy, magnetic susceptibility, conductivity, and thermal analysis (TG, DTA). Furthermore, the determination of complex stoichiometry and identification of their octahedral structural configuration were facilitated through the application of Job's techniques and molar ratio analysis. Complementing the experimental analyses, computational investigations via Density Functional Theory (DFT) were conducted to garner deeper insights into the structural, orbital, and electronic attributes of the compounds. Moreover, the anti-inflammatory properties of these synthetic compounds were scrutinized through in vitro assays, notably highlighting the superior efficacy of the C1 complex among the examined compounds. To validate their therapeutic potential, a comparative assessment was made against established anti-inflammatory agents. The hierarchy of anti-inflammatory activity among the metal complexes is established as follows: C1 > C2 > L, with the C1 exhibiting the highest potency. Additionally, a molecular docking study was executed to elucidate the compounds' interaction with the cyclooxygenase-2 (COX-2) enzyme (PDB ID: 5IKT), further corroborating their potential pharmacological relevance.