Synthesis, spectral, crystal structure, drug‐likeness, in silico, and in vitro biological screening of halogen [Cl, Br] substituted N‐phenylbenzo[g]indazole derivatives as antimicrobial agents

Abstract

AbstractThe N‐phenylbenzo[g]indazole derivatives, 3‐(4‐chlorophenyl)‐3,3a,4,5‐tetrahydro‐N‐phenylbenzo[g]indazole‐2‐carbothioamide (4CLPBIC), 3‐(4‐bromophenyl)‐3,3a,4,5‐tetrahydro‐N‐phenylbenzo[g]indazole‐2‐carbothioamide (4BRPBIC), and 3‐(3‐bromophenyl)‐3,3a,4,5‐tetrahydro‐N‐phenylbenzo[g]indazole‐2‐carbothioamide (3BRPBIC), were synthesized by the one‐pot green amalgamation of solvent‐free granulating methodology procedure at room temperature. The synthesized crystals were characterized by single‐crystal X‐ray diffraction (SC‐XRD), FT‐IR, FT‐Raman, NMR, and UV–Vis techniques. The molecular geometries from XRD experimental values of synthesized compounds 4CLPBIC, 4BRPBIC, and 3BRPBIC in the ground state are compared theoretically by applying the density functional theory (DFT), a method with the B3LYP/6‐311G(d,p) basis set using Gaussian 09 software. The vibrational assignments of the synthesized compounds were studied based on potential energy distribution (PED) by the VEDA4 program. The scaled DFT/B3LYP/6‐311G(d,p) results show the best agreement with the experimental values. Computational 1H and 13C NMR were acquired by utilizing gauge‐independent atomic orbital (GIAO) procedure, and chemical shift results are in good agreement with the experimental values. A web‐based theoretical investigation was performed to understand the drug‐likeness and ADMET properties of the compounds. Molecular docking studies were carried out against bacterial cholesterol inhibitor block and inhibitor of lanosterol‐14α‐demethylase CYP51 used in the treatment of topical and systemic mycoses in fungal to understand the inhibitory activity of synthesized compounds. The synthesized molecules were also tested for antibacterial and antifungal activities.