Synthesis, spectroscopic characterization, electronic and docking studies on novel chalcone derivatives (3DPP and 5PPD) by experimental and DFT methods

Abstract

In the present study, 3-(2,4-Dichloro-phenyl)-1-pyridin-3-yl-propenone (3DPP) and 5-Phenyl-1-pyridin-3-yl-penta-2,4‑dien-1-one (5PPD) are synthesized and characterized by NMR, UV–Vis, FT-Raman and FT-IR spectroscopic methods. Theses spectroscopic results were correlated with the results of computational studies done using Gaussian software. The optimization procedure for the molecule gives minimum energy confirmation of the structure. The B3LYP/6–311++G (d, p) basis set is used for obtaining the optimized structure. Comparisons of computed geometrical parameters are done with experimental data. Experimental values for FT-Raman for range 4000–50 cm−1 and FT-IR spectra for range 4000–400 cm−1 of 3DPP and 5PPD are obtained. Vibrational assignments of the molecules are determined in detail with support of PED i.e. potential energy distribution. Theoretical NMR (1H and 13C) analysis is conducted by GIAO method for its structural characterization and comparison is done with experimental values of chemical shifts. Experimental UV–Vis spectrum is obtained in DMSO solvent and compared with the theoretically computed spectrum with the help of Time-Dependent DFT method. The molecular docking studies performed with periplasmic proteins (PDB ID: 2IPM, 2IPLand 5Y2O) for both molecules. In addition to these studies other analyses such as MEP, FMO, NBO, and NLO have been conducted to understand the nature of molecules.