Synthesis, quantum chemical insights, vibrational spectral elucidation, insecticide likeness and docking analysis of the insecticide active novel molecule 2-(4-nitrophenyl)-(3,5-difluoro-pyridine-6-yl)-1,3,4-oxadiazole

Oxadiazole derivatives containing pyridine moiety were biologically active molecules that have been widely applied in recent years in research on pesticides, particularly insecticides. In this work, a newly synthesized 2-(4-nitrophenyl)-(3,5-difluoro-pyridine-6-yl)-1,3,4-oxadiazole compound was characterized using spectroscopic techniques. The quantum chemical computations based on density functional theory were employed to investigate the molecular configuration of title compound. The modes of vibrations of the compound were identified through potential energy distribution, and the results were consistent with the experimental infrared and Raman data. Natural bond orbital assessment evaluated the significant donor-acceptor interactions within the molecule. The frontier molecular orbital analysis was performed to obtain global reactivity parameters. The molecular electrostatic potential was used to visualize the chemical reactivity and charge distribution of the molecule. From the nuclear magnetic resonance spectra, the carbon atoms bonded with nitrogen and oxygen atoms show the up-shielded peaks. The chemical implication of molecule was explained using electron localization function and localized orbital locator analysis. Moreover, the molecular docking studies performed for the newly synthesized compound revealed an efficient interaction with the acetylcholine receptor and exhibited better binding affinity than commercialized insecticides. Whilst, the physicochemical properties were assessed using the insectiPAD webtool to comprehend the insecticidal properties of title compound. Finally, the quantitative structure activity relationship study of 2-(4-nitrophenyl)-(3,5-difluoro-pyridine-6-yl)-1,3,4-oxadiazole showed higher activity (pLC50 = -1.43) against Mythimna separata, as compared to commercial insecticide avermectin (pLC50 = -1.47). These results provided that title compound could be used as a template for future insecticide investigations.