Quantum mechanical, spectroscopic and docking studies of (2E)-1-(4-aminophenyl)-3-(4-benzyloxyphenyl)-prop-2-en-1-one Chalcone derivative by density functional theory - A prospective respiratory drug.

Theoretical investigations on the molecular geometry, vibrational and electronic environment of (2E)-1-(4-aminophenyl)-3-(4-benzyloxyphenyl)-prop-2-en-1-one APBPP) are presented for the first time. The vibration frequencies simulated were thoroughly analysed employing DFT/B3LYP using 6-311++G(d,p) basis set and compared with experimental FT- Raman and FT- IR data which showed good agreement vice-versa. Optimised molecular equilibrium geometry of the title compound was carried out. Vibrational assignments of wave numbers with PED (potential energy distribution) was done using VEDA software and the quantum chemical calculations of the molecular geometry were scaled using quantum mechanics. The title molecule showcased excellent results on HOMO - LUMO energies, NMR chemical shifts, 3.73 eV band gap, electronegativity (χ), chemical potential (μ), softness (S), global hardness (η). The low softness value (0.261) and thehigh value of electrophilicity index (4.0323) explains the biological activity of the title molecule. The reactive sites of APBPP were thoroughly investigated by Mulliken charges, MEP (Molecular electrostatic Potential) and Fukui functions. Thermo dynamical environment of the title compound for different temperatures were studied which reveals the correlations between entropy (S), heat capacity (C) and enthalpy changes (H) with temperatures. The title compound was docked into the reactive sites of antiviral (SARS-CoV-1,2) and anticancer protein using molecular docking tool and it showed excellent results compared to the ongoing clinical trials. The paper explains the experimental analysis which are in line with the quantum calculations and presents an optimistic evidence via Molecular docking studies. The synthesized compound against various panels of microorganism projects its ability to be the most potential drug to treat various pathologies in pharmacy Industry.