Synthesis And Bioactivity Of Novel Acyl（thio）urea Derivatives

As a chitin synthesis inhibitor,benzoylurea compounds not only have excellent insecticidal,acaricidal and bactericidal activities,but also are safe to humans and animals due to their unique mechanism of action.Therefore,these compounds and their derivatives have always been the focus of the creation of new pesticides.In order to develop green pesticides with high activity,broad spectrum,insecticidal,acaricidal and bactericidal activities,a series of new acyl（thiourea）derivatives were designed and synthesized by using active substructure splicing method and similar synthesis method,using a variety of compounds with high biological activity as precursors.Among them,six new benzoyl thiourea compounds were designed and synthesized with licodiurea as the lead compound and 2,6-difluorobenzoic acid as the raw material;A total of fourteen novel fluorinated pyridine formyl urea compounds and fourteen fluorinated pyridine formyl thiourea compounds were designed and synthesized by using lice mite urea and fluoroacetamide as precursors and 2,3-dichloro-5-trifluoromethylpyridine as raw materials;Seven new fluoronicotinylureas were designed and synthesized with licodiurea and fluridoxamide as precursors and 4,4,4-trifluoroacetoacetate ethyl ester and cyanoacetamide as raw materials;A total of twenty new fluoroether nicotinyl thiourea compounds were designed and synthesized from 2-chloronicotinamide,fluorophenol and fluoroalcohols.In this paper,a total of 61 new acyl（thio）urea compounds in five series were synthesized,the synthesis process was optimized,the structure was characterized,the ~1H NMR,¹³C NMR and LC-MS spectra of the target compounds were obtained,and their molecular structures were determined.Five compounds with high biological activity were screened out by preliminary indoor determination of insecticidal,acaricidal and bactericidal biological activities.Among them,the insecticidal activity of two new benzoyl thiourea compounds is higher than that of Lufenuron,at the concentration of 1 mg/L,the biological activities of compoundsⅡ-4b andⅡ-4c against the third instar larvae of Diamondback moth（Plutella xylostella）were 79%and 75%respectively,and the acaricidal activity of the three compounds was higher than that of Propargite,the bioactivity of compoundⅡ-4b against Carmine spider mite（Tetranychus cinnabarinus）was 66%;The insecticidal activities of fourteen new fluorinated pyridine formyl thiourea compounds and fourteen fluorinated pyridine formyl urea compounds were lower than those of Lufenuron and Propargite;The insecticidal activity of seven new fluoronicotinylureas was lower than that of Lufenuron,but the insecticidal activity of two compounds was higher than that of Propargite.When the application concentration is 0.1 mg/L,the acaricidal activities of compoundsⅤ-7d andⅤ-7e are 63%and 78%respectively,showing ultra-high acaricidal activities;The twenty new fluoroether nicotinyl thiourea compounds have good broad-spectrum bactericidal activity.At the test concentration of 50 mg/L,most compounds have an inhibition rate of more than 50%on nine kinds of crop pathogens,among them,compoundⅥ-7b₁c₂ has the highest activity.At the concentration of 5 mg/L,the inhibition rate of compoundⅥ-7b₁c₂ on Tomato Early Blight（Alternaria solani Soraauer）and Rape Sclerotinia sclerotiorum（Sclerotinia sclerotiorum（Lib.）de Bary）is more than 50%.The five selected target compounds have ultra-high biological activity,novel structure,easy synthesis and great application and development value.