Study On The Synthesis And Biological Activities Of Thiazole Derivatives Of Nicotinic Insecticide

Neonicotinoid insecticides study is one of the environmentally friendly pesticideresearch in recent years. It works on insect central nervous system, and it has highefficient, selective, and the advantages of safety to mammals, and no resistance withtraditional pesticide. Heterocyclic compounds are popular in the field of organicchemistry in recent years. Five-membered heterocycles are closely related to biologyand widely exist in nature. For example, a lot of nucleic acids, hormones, and alkaloidscontain five-membered heterocycles. Thiazole and imidazole are important medicine,pesticide intermediates. They are five-membered heterocycles. Thiazole and itsderivatives is an important heterocyclic compounds in Chemical, biological,pharmaceutical, pesticide and agricultural areas. Thiazole has the very high applicationvalue. The different structures of the thiazole derivatives have different biologicalactivity. Research on new type of thiazole derivatives and test on their biologicalactivity has become the focus in the field.In this paper, we summarized the structure, classification, synthesis, application,development history, the research progress and mechanism of neonicotinoidinsecticides. The different reactive groups were introduced in thiazole derivatives usedN alkylation reaction and Knoevenagal condensation reaction. Seventeen new thiazolederivatives were synthesis. Its structure was given below:The synthesized compounds were confirmed by1H NMR, IR and part of thecompounds were confirmed by GC-MS. We measured part of their physical andchemical properties. We optimized the reaction steps. Biological activity tests showedthat some compounds have certain biological activity. The main contents andcontbriutions of the research are as follows: 1) We designed and synthesized compounds17new thiazole derivatives using Nalkylation reaction and Knoevenagal condensation reaction. Its structure wereconfirmed by1H NMR, IR and GC-MS spectrum. And the biological activity ofcompounds was tested.2) We compared the molar ratio, solvent, temperature and catalyst in the step ofreaction. We optimized the reaction steps, and higher yield synthesis route was given.3) We tested the biological activity of the synthesized compounds. Biological testresults showed that part of the compound has a certain biological activity. Wecompared differences of the activity. When the concentration is200ppm, thecompound1e against Carmine Spider Mite rate can reach87%and the compound2dagainst Bean Aphid rate can reach52%.