Synthesis, Spectroscopic (FTIR, FT-Raman and UV-Vis), Structural Investigation, Hirshfeld, AIM, NBO, Chemical Reactivity, In-Vitro and In-Silico Analysis of N-(2-Hydroxyphenyl)-4-Toluenesulfonamide

Abstract

The prospective antimicrobial molecule N-(2-Hydroxyphenyl)-4-methylbenzene sulfonamide has been synthesized and characterized by single crystal XRD, FT-IR, FT-Raman, UV-Vis spectra and antimicrobial analysis. The quantum chemical computations of energies, geometrical structure, charge transfer and vibrational wavenumbers were carried out using density functional method (DFT/B3LYP) with 6-311 G (d, p) basis set. The complete vibrational assignment for the vibrational modes were performed with vibrational energy distribution analysis (VEDA4) and these assignments were compared with the experimental FT-IR and FT-Raman spectrum. In FT-IR spectrum, strong intense absorption bands are observed at 3408 and 3273 cm−1 corresponding to OH and NH group, which is involved in N–H…O and C–H…O intermolecular interaction. Hirshfeld surface analysis determines the stability of crystal packing within the crystal packing ensured by C–H…O and O–H…O intermolecular interactions. The 2 D fingerprint plot shows that H…H, C…H and O…H interaction exhibit the most significant contribution. Natural bond orbital (NBO) analysis suggests that the electronic transitions are mainly attributed to π→π* transitions. The strength of N–H…O and C–H…O intermolecular interactions were analyzed using reduced density gradient (RDG) analysis and atom in molecule (AIM) analysis. The frontier molecular orbital analysis reveals the possibility of charge transfer within the molecule. Electrophilic and nucleophilic sites were found by molecular electrostatic potential (MEP) analysis and Fukui analysis. Molecular docking shows that sulfonamide and hydroxyl groups are biologically active through their hydrogen bonding interaction with amino acids, which reveals the antimicrobial activity of the compound. Antimicrobial activity of the compound was confirmed by the Kirby Bauer disk diffusion method. The band gap energy and antimicrobial evaluation of the title molecule were compared with the reported relative compounds, which reveals the significant antimicrobial activity. Besides, drug likeness and ADMET (absorption, distribution, metabolism, excretion and toxicity) prediction analysis suggest that the title compound can be used as an antimicrobial drug.