Spectroscopic (FT-IR, FT-Raman, UV, NMR, NLO) investigation, molecular docking and molecular simulation dynamics on 1-Methyl-3-Phenylpiperazine

Abstract

The title compound was analyzed, by recording FT-IR (4000-400 cm−1) and FT-Raman (4000-100 cm−1) spectra in solid phase, 1H and 13C NMR in CDCl3 (deuterated chloroform) and UV spectrum (200–400 nm) in solid phase and in ethanol solution. Conformational analysis was done using semi-empirical method PM6. The computed wavenumbers obtained from B3LYP and B3PW91 functionals along with 6–311++G (d, p) basis sets were scaled so as to agree with the experimental values and the scaling factors have been reported. All fundamental modes have been assigned based on the potential energy distribution (PED) values and the structure of the molecule was analyzed in terms of parameters like bond length, bond angle and dihedral angles through B3LYP and B3PW91 functionals along with 6–311++G(d,p) basis set. The observed HOMO-LUMO mappings reveal the different charge transfer possibilities within the molecule. The percentage contribution of a group to each molecular orbital was calculated using Gauss Sum program. Natural bond orbital analysis was computed and possible transition were correlated with the electronic transitions. Mulliken charges, electrostatic potential charges and natural charges are also predicted. The theoretical 1H and 13C NMR chemical shifts were computed using B3LYP functionals using 6-311++G (2d, p) basis sets. The temperature dependence of the thermodynamic properties; heat capacity, entropy and enthalpy for the title compound were also determined by B3LYP functional with 6–311++G (d, p) basis set. Molecular docking study shows that the title compound might exhibit inhibitory activity against Clostridium botulinum (2J3X). The interaction of the ligand (title molecule) with 2J3X for 2 ns duration and radial distribution function have been observed through molecular dynamics simulations.