Insecticidal Evaluation, Molecular Docking, and Structure-Activity Relationship Study of Some Synthesized Thiazole-Owing Hydrazone Derivatives Against Spodoptera frugiperda under Laboratory Conditions.

Objective: The "fall armyworm" also known as Spodoptera frugiperda, is a maize pest that is native to North America. It invaded Africa in 2016 and caused serious economic damage, forcing the continent's nations to take swift action to fend off this new invading pest. It is urgently necessary to produce powerful insecticides for the efficient management of this insect pest since this parasite is a novel invading species and its resistance to insecticides has to be investigated. Methods: The synthesized thiazole-owing hydrazone derivatives are the subject of the first study on the harmful effects they cause, followed by structural relationships. Following the stated protocols, four molecules of thiazole-owing hydrazone derivatives were synthesized as pure active ingredients, and their efficacy as potential insecticides against S. frugiperda was tested. Results and Discussion: The toxicity data exhibited that compound (V) with LC50 of 13.66 and 106.25 ppm was more toxic against the 2nd and 4th larvae instars, respectively, than other synthesized compounds; the other screened compounds showed weak to strong toxicological activity against S. frugiperda. A molecular docking investigation of four synthetic compounds (III–VI) was performed against acetylcholinesterase (AChE). The molecular docking results revealed that compound (V) has the more negative docking score and best binding (docking score = –9.01 kcal/mol), followed by compounds (III), (IV), and (VI) with docking scores of –8.76, –8.53, and –7.41 kcal/mol, respectively. The protein-ligand docking postures revealed that these substances exhibited a strong affinity for the target enzyme's active site (Protein Data Bank ID: 2ACE). This work suggests that these substances may have insecticidal and AChE inhibitory properties, and it may be possible to further explore them in the process of creating pesticides that target AChE. [ABSTRACT FROM AUTHOR]