Synthesis And Antimicrmatic Activities Of N-substituted Phenyl-N'-substituted Benzimidazol-2-yl Acylureas

Since the 1980s of the 20th century, the acylureas have caused the concern of the chemical field owing to their insect killing, acaricidal, fungicidal, antivirus, herbicidal and plant growth regulating activities. This kind of compounds have such advantage as high selectivity to non-target living creature, special action mechanism, high surroundings safety, low concentration and quick degradation that traditional agrochemicals can't compare to, was called"the pesticides of 21 centuries". Therefore,synthesis and application of the acylureas have become the hot field of the synthesis of the pesticides.Because of the heterocylcle of pesticide have various structures,all kinds of substitutes, better bioactivities, better safty, being suit for future demand ,it gradually becomes the main trend of the future pesticide .Since1960, it is reported that all kinds of 2-aminobenzimidazole is a wide strong systemic fungicide by Krapping. The development of the benzimidazole and it's derivatives, especially two replacements of benzimidazole, is regarded as a category with a variety bioactivities of heterocyclic. Since the emergence of these fungicides, bactericides developed to a new stage, and there is a new systemic fungicide, and fungicides in the history of this epoch-making significance.In the article, we dissertated comprehensively the functional mechanism, the relationship of structure, the synthetical methods and the safety of acylureas and the benzimidazole. In order to seek insecticides with good biological activities, we have modified the main structure of acylureas by Bioisosterism Principles , Activity Montage Principle and Structure Link Wory , connected benzimidazole, urea bridge and substitutedaniline with the main structure , and synthesized 29 new N-substituted phenyl -N′- substituted benzimidazol-2-yl acylureas.Target compounds have been synthesized by condensation of the aromatic nucleus and amino heterocylcle with acyl- isocyanates in absolutely anhydrous and aprotic solvent.Their structures were confirmed by IR,1H NMR and Elemental analysis. Based on the idiographic structure, we discuss synthesis condition, spectrum properties and physic-chemical constant of the target compounds at last. The title compounds are listed as follows.ⅠN-substituted phenyl -N′- -benzimidazol-2-yl acylureasⅡN-substituted phenyl -N′-6-chlorbenzimidazol-2-yl acylureasⅢN-substituted phenyl -N′- 6-fluorbenzimidazol-2-yl acylureasIn the article, the antifungal activities of three series compounds to Botrytis cinerea pers and Sclerotinia sclerotiorum were respectively tested by the mycelium growth rate method , compared with Carbendazim and Thiophanate-methyl. The results indicated that they had good antifungal activity to Botrytis cinerea pers and Sclerotinia sclerotiorum,and the antif-ungal activity of N-substituted phenyl -N′-6-chlorbenzimidazol-2-yl acylureas and N-substituted phenyl -N′- 6-fluorbenzimidazol-2-yl acylureas is better than N-substi-tuted phenyl -N′- benzimidazol-2-yl acylureas.Their toxicities were significantly higher than that of Carbendazim and Thiophanatemethyl and were equal to them. Based on the bioactivities , we discuss and analyse the relalitionship between bioactivities and structure, and the bioactivities of benzimidazoles which have Fluor or chlor are better than others.