Synthesis, Density Functional Theory, Insecticidal Activity, and Molecular Docking of Some N -Heterocycles Derived from 2-((1,3-Diphenyl-1 H -Pyrazol-4-yl)Methylene)Malonyl Diisothiocyanate

The extensive pharmacological applications of the pyrazole-based compounds stimulated us to synthesize the highly functionalized, pyrazolylmalonyl diisothiocyanate derivative (2) via treating 2-((1,3-diphenyl-1H-pyrazol-4-yl)methylene)malonyl dichloride (1) with ammonium thiocyanate in acetonitrile at room temperature. The diisothiocyanate derivative 2 was subsequently conducted with a double molar ratio of different nitrogen nucleophiles like 4-acetylaniline, 2-aminobenzoic acid, 6-aminothiouracil, 2-aminothiadiazole derivative, hydrazine, phenylhydrazine, thiophene-2-carbohydrazide, 2-hydroxybenzohydrazide, 2-cyanoacetohydrazide, thiourea, thiosemicarbazide, 2-aminoaniline, and thiocarbohydrazide, aiming to construct some valuable heterocyclic systems. The synthesized compounds were screened for their insecticidal activity against healthy late third instar larvae P. interpunctella and Nilaparvata lugens and the results showed that pyrimidinethione, thiadiazolotriazine, and tetrazinethione derivatives exhibited the highest insecticidal potency that are supported by DFT stimulation and their molecular docking.