Molecular spectroscopic assembly of 3-(4-chlorophenyl)-5-[4-(propane-2-yl) phenyl] 4, 5-dihydro-1H pyrazole-1-carbothioamide, antimicrobial potential and molecular docking analysis

Abstract

A novel pyrazole derivative 3-(4-Chlorophenyl)-5-[4-(propane-2-yl) phenyl] 4, 5-dihydro-1H –pyrazole-1-carbothioamide (CPDPC) was optimized to its minimum energy level using density functional theory (DFT) method. The complete optimization of the molecular equilibrium geometry of the title molecule was carried out. Quantum chemical calculations of the equilibrium geometry and the complete vibrational assignments of wavenumber using potential energy distribution (PED) were carried out using DFT method (B3LYP) with 6–311++G (d, p) basis set. Frontier molecular orbitals such as highest molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and molecular electrostatic potential surface on the title molecule are predicted for various intramolecular interactions that are responsible for the stabilization of the molecule. Stability of the molecule arising from hyper conjugative interactions, charge delocalization and intramolecular hydrogen bond-like weak interaction has been analyzed using 6–311++G (d,p) basis set. From the UV–Visible spectrum, the electronic properties such as excitation energies, oscillator strength and wavelength are calculated by DFT method. The title compound has been screened for their in vitro antimicrobial activity against four bacteria and two fungal strains using disc diffusion and broth microdilution susceptibility assays. From the molecular docking studies, it is evident that the Cl atom attached to phenyl ring and carbothioamide group attached to pyrazole ring is crucial for binding and the result draws us to the conclusion that the compound might exhibit antimicrobial activity.