Synthesis, cytotoxic screening and molecular docking, DFT calculation of novel furan-heterocyclic derivatives as insecticidal agents

The insecticidal furan-2-carbaldehyde thiosemicarbazone (1) as staring compound underwent a nucleophilic substitution reaction with different reagents, chloroacetyl chloride, chloroacetic acid. 1,4-dibromobutane-2,3-dione and also, with different activated reagents 2-cyanoacetohydrazide, phthalic anhydride, and 2-chloroquinoline-3-carbaldehyde as good yields. The structures of these compounds were confirmed by elemental and spectral analyses. The majority of the synthesized compounds were assessed for their insecticidal activity towards three insects, Cryptoblabes gnidiella, Retithrips syriacus and Spodoptera frugiperda under laboratory conditions and promising results were obtained, with encouraging outcomes observed. Compounds 5, 7, 9, 11 and 15 were found to the most effective than other compounds on all insects. Also, R. syriacus insects are more affected than C. gnidiella and S. frugiperda after one day of treatment with LC₅₀ values 15.68, 18.90, 58.04, 17.81, and 42.21 μg/mL respectively, comparing with positive control LC₅₀, 8.90 μg/mL. Furthermore, biochemical parameters of five enzymes of S. frugiperda; Acid Phosphatase, alkaline phosphatase, aspartate transferase, alanine transaminase, and acetylcholinesterase enzymes were conducted at LC₅₀ value of the highly toxic compounds. Density functional theory calculations were employed to optimize the molecular geometry and compute the electrostatic potential, complemented by molecular docking to predict the most acceptable score and root mean square deviation and affinities of the synthesized compounds.