New 3d multifunctional metal chelates of sulfonamide: Spectral, vibrational, molecular modeling, DFT, medicinal and in silico studies

Abstract

We are reporting a new synthetic design of sulfonamide entangled Schiff base ligands as H2L1 and H2L2 from 4-amino-N-(3-methyl-1,2-oxazol-5-yl)benzene-1-sulfonamide and their reaction with the bivalent metals (VO2+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+) to yield metal complexes (1)–(12). The ligands and metal complexes are studied experimentally with different spectroscopic and analytical approaches (UV–Vis, FT-IR, LC-MS 1H and 13C NMR). The ligands practiced their coordination compounds with the 3d-metal ions through phenyl hydroxyl and azomethine nitrogen, resulting in square-planar (only for vanadium) and octahedral morphologies. All complexes are structured in of 1: 2 (metal: ligand) stoichiometry ratio. The indicators of density functional theory are designed to validate geometric structures and their properties. Comprehensive antimicrobial activities, targeting six pathogenic bacteria and fungi are operated by disk diffusion bioassay. To establish their role as multifunctional ligands, promising in vitro assays have been adopted to benchmark their candidature during Alzheimer's disease (anti-choline inhibitor), microbial resistance, anti-oxidant potentials, as well as HIV protease and α-amylase inhibitory activity. The forecasting of ADMET/toxicity characteristics was conducted out through ADMET Prediction™ to analyze the reliability of the drug-receptor complex. The results show that most compounds show antibacterial properties as well antifungal activities against these organisms. The VO+2 and Co+2 complexes indicated a powerful antibacterial effect against the Gram (-) strains. Anti-oxidant interactions were analyzed using three different strategies..