Design,Synthesis And Biological Activity Of Novel Thiazole Compounds

Thiazole（pyrazole）compounds have broad-spectrum biological activities.They can be used not only as fungicides,but also as insecticides,acaricides,herbicides,plant growth regulators and other pesticides and anti-inflammatory,anti-tumor and other medical fields.In this paper,in order to develop new thiazole（pyrazole）compounds and solve the current problem of pesticide resistance,15 new thiazole amide compounds were synthesized by the method of active substructure splicing,using thiadiazole as the lead compound,2,6-difluorobenzonitrile and 2-chloronicotinonitrile as the starting materials,respectively.Starting from 2,6-difluorobenzoic acid,six novel 1,2,4-oxadiazole thiazole compounds were synthesized by using oxone and thiamethoxam as lead compounds.Using bifenazate as the lead compound,2,6-difluorobenzoic acid,2,3,4,5,6-pentafluorobenzoic acid and 2-fluorobenzoic acid as the starting materials,three series of 33 novel fluorinated benzothiazole esters were designed and synthesized.The thiazole ring was synthesized from formaldehyde and cysteamine hydrochloride,and then six thiazolidine esters were synthesized by splicing with the active group.A series of pyrazole-containing compounds,including eight pyrazole acrylonitriles and two pyrazole amides,were designed and synthesized by the active substructure splicing method using acetamiprid and lufenuron as lead compounds.The synthesized compounds were characterized by ¹H NMR,¹³C NMR,HRMS and single crystal diffraction analysis.At the same time,the synthesis process of the target compounds was explored,and a new method suitable for industrial production was found.The biological activity of the synthesized target compounds was tested in the laboratory,and the structure-activity relationship of the synthesized compounds was preliminarily discussed.Among them,when the mass concentration of compounds IV1-a,IV1-e,IV1-g and V3a2b2 was 10 mg/L,the lethal rate to Plutella xylostella was100%.When the mass concentration was 1 mg/L,the lethal rate of compounds IV1-e,IV1-g and V3a2b2 to Plutella xylostella could still reach more than 80%.At the mass concentration of 100 mg/L,the lethality of compounds V3a1b1 and V3a2b2 to T.urticae could reach 90%.The mortality of compounds II2a,II2e and II2i to aphids was more than 85%.At the mass concentration of 5 mg/L,the hatching inhibition rates of compounds VI2 b and VI2 e on the eggs of T.urticae were 76%and 89%,respectively,and the hatching inhibition rate of the control reagent cyflumetofen was 77%at this concentration.The above compounds can be used as lead compounds to provide theoretical and data basis for the subsequent development of new pesticides.Among them,compounds VI2 b and VI2 e have higher hatching inhibition rate on T.urticae eggs than cyflumetofen,and the raw materials are easy to obtain and the synthetic route is simple,which has the potential for commercialization.