Spectroscopic investigation, vibrational assignments, Fukui functions, HOMO-LUMO, MEP and molecular docking evaluation of 4 – [(3, 4 – dichlorophenyl) amino] 2 – methylidene 4 – oxo butanoic acid by DFT method

Abstract

The experimental FT-IR and FT-Raman spectra of 4 – [(3, 4 –dichlorophenyl) amino] 2 – methylidene 4 – oxo butanoic acid (DMOA) has been recorded. Quantum chemical calculations of geometry and vibrational wavenumbers of the title compound are carried out theoretically and were compared with the experimental results. NBO analysis, HOMO-LUMO, hardness, softness, first hyperpolarizability and molecular electrostatic potential results are also reported. The negative regions of the MEP are related to electrophilic reactivity and the positive regions to nucleophilic reactivity, as shown in the MEP plot and the title compound has several possible sites. Natural bonding orbital (NBO) assessment was completed with a reason to clarify charge transfer, inter hybridization and delocalization of electron density within the molecule. A computation of the first hyperpolarizability of the compound indicates that this class of substituted butanoic acid may be a good candidate as an NLO material. The study is extended to calculate the binding energy of the title compound with suitable protein by Autodock software. The RDG scatter graphs and the RDG gradient isosurface further illustrate that the interactions between DMOA belong to the van der Waals interactions.