Density functional studies and spectroscopic analysis (FT-IR, FT-Raman, UV-visible, and NMR)with molecular docking approach on an antifibrotic drug Pirfenidone

This present research work contributes to the findings of geometrical structure, vibrational frequencies and respective assignments with the compatible electronic, optical, nonlinear and thermodynamic properties of an antifibrotic drug. The theoretical characterization using density functional theory with the higher-order basis set 6-311++G(d,p)was treated with FT-IR, FT-Raman,UV-visible, and NMR spectroscopic characterizations. Theoretical and experimental observations of all the spectroscopic characterizations such as Infrared, Raman,UV-visible and NMR were compared. The targeted drug is a very good antifibrotic in nature, theoretically proved using the molecular docking approach. Time-dependent density functional theory emphasized the comparison of the highest occupied and the lowest unoccupied molecular orbital energy gap with the ultraviolet absorption spectra. Furthermore, a small scaling factor eradicates the solid to gas phase switch in the vibrational spectra of Infrared and Raman characterization. The target drug 5-methyl-1-phenyl-1,2-dihydropyridine-2-onewidely called Pirfenidone(generic name) is docked with two different receptors such as antifibrotic and antiin-flammatory origins. All the results of the titled antifibrotic drug were discussed with the proper literature survey. (C) 2019 Elsevier B.V. All rights reserved.