One-pot synthesis, spectroscopic characterizations, quantum chemical calculations, docking and cytotoxicity of 1-((dibenzylamino)methyl)pyrrolidine-2,5-dione

Abstract The investigations of stabilization energy, bond order, intra-molecular interactions and energy gap of pharmaceutical drugs are useful for understanding their behaviour. A new Mannich base molecule 1-((dibenzylamino)methyl)-pyrrolidine-2,5-dione (SBF) was synthesized through sequential Mannich reactions of an imide with an aldehyde and the intermediate obtained are reacted with secondary amine to get the desired product. The entire molecular geometry of the SBF molecule was confirmed by single crystal XRD studies. The crystal structure of SBF molecule was found symmetrical and planar with anti-periplanar orientation of C O group and nitrogen atom. The theoretical computations were performed using B3LYP/6-31G(d, p) level of basis set. The chemical environment of carbon and protons were shown with 13C and 1H NMR spectral analysis, respectively. The molecular weight of the title molecule was determined by mass spectrum. The thermal stability of the SBF molecule up to 270 °C was exposed by thermogravimetric (TG) and differential scanning analysis (DSC). The natural bonding orbital (NBO) analysis data revealed the highest stabilization value of E(2) for transfer of electron density from succinimide to the antibonding molecular orbital of the dibenzyl ring were found to be 51.51 and 50.31 kJ/mol. The energy of HOMO-LUMO, PDOS, OPDOS, RDG of the title molecule have also been carried out. The protein-ligand relationship was well revealed by molecular docking studies. The cytotoxic activity of the SBF molecule was evaluated by MTT assay on cell line A549.