Influence of acetyl, hydroxy and methyl functional groups on 2-phenylbutanoic acid by quantum computational, spectroscopic and ligand-protein docking studies

• Published in: Journal of molecular structure Vol. 1188; pp. 99 - 109
• Main Authors: Raajaraman, BR, Sheela, N.R., Muthu, S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2019
• Subjects: DFT; FT-IR; FT-Raman; Molecular docking; NBO; NLO; NLO; FT-IR; NBO; DFT; FT-Raman; Molecular docking
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2019.03.093

2-Phenylbutanoic acid (2PBA) and its functional derivatives 2-amino-2-Phynylbutanoic acid (2APBA), 2-hydroxy-2-Phenylbutanoic acid (2HPBA) and 2-methyl-2-phenylbutanoic acid (2MPBA) are analyzed by density functional theory (DFT) calculations at B3LYP level with basis set 6-311++G(d,p). Experimental studies like FT-IR, FT-Raman, and UV–Visible spectra are carried out and compared with the theoretical molecular geometry and vibrational frequencies. To study donor and acceptor interactions natural bond orbital (NBO) analysis were performed. The observed UV–Vis spectrum compared with the time-dependent TD-DFT analysis gives band gap energies, oscillator strength, and the absorption wavelengths of different molecules. The hyperpolarizability analysis shows that the nonlinear optical (NLO) properties of the 2PBA, 2APBA, 2HPBA and 2MPBA compounds. The visual bio-active areas of the molecule are estimated by Molecular electrostatic potential (MEP). The important thermodynamic properties like heat capacity, entropy, and enthalpy of the 2PBA, 2APBA, 2HPBA, and 2MPBA were calculated at different temperatures. Molecular docking methods were employed with 2PBA, 2APBA, 2HPBA and 2MPBA molecules with the same set of receptors (proteins) to find the best of four molecules for drug identification. [Display omitted] •Charge transfer interactions are analyzed by NBO.•NLO behaviors of the derivatives are found.•The reactive areas are identified by molecular electrostatic potential.•Thermodynamical properties are analyzed.•Molecular docking studies have been discussed.