Quantum chemical calculations, spectroscopic properties and molecular docking studies of a novel piperazine derivative

Abstract This work is devoted to investigating the molecular geometry, biological activities, electronic and vibrational characteristics of 1-phenylpiperazin-1,4-diium nitrate monohydrate (1PPNO3) by combining quantum chemical calculations with molecular docking. The geometric structure has been optimized with the Density functional theory (DFT) method using B3LYP-D and WB97XD functional. By referring to the values of the RMSD, the DFT calculation reproduces well the bonds lengths and the angles. Atoms-in-molecules, reduced density gradient and electron localization function analyses have been carried out to study the intra and intermolecular interactions within molecule, in particular to study the properties of hydrogen bonds. NBO orbital analysis has been reported to study electronic exchanges and transfer reactions between donor and acceptor compounds. In addition, Hirshfeld Surface Analysis (HS) was evaluated in order to discern the interactions in the crystal structure. The molecular electrostatic potential was calculated to identify the electrophilic and nucleophilic sites which favor the formation of hydrogen bonds. Inhibitor characteristics of 1PPNO3 on Kalirin-7 and monoamine oxidase B enzymes with several selective inhibitors were examined by molecular docking. Finally, thermal (DTA) and thermogravimetric (TG) analyses for the title compound have been conducted and the thermodynamic properties were determined via model chemistry.