除草活性を有する新規イミダゾール-4-カルボキサミド誘導体の合成研究

概要

論文の詳細を見る
A series of novel 1-(substituted phenyl)imidazol-4-carboxamides substituted with cyano and trifluoromethyl groups at the 5 position of the imidazole ring were synthesized, and their herbicidal activities were evaluated against various weeds under paddy and upland field conditions. 5-Cyanoimidazol-4-carboxamides were synthesized by regioselective hydrolysis of the 4-cyano group of 4,5-dicyanoimidazole followed by amidation of the carboxylic acids obtained. On the other hand, 5-(trifluoromethyl)imidazol-4-carboxamides were easily obtained by amidation of the corresponding imidazol-4-carboxylic acids, which were prepared by cyclic condensation of N-(substituted phenyl)imidoyl chlorides with ethyl isocyanoacetate followed by hydrolysis of the ester moiety. The herbicidal activity of these derivatives was primarily influenced by the substituent at the 5 position of the imidazole ring, and the trifluoromethyl group was much more efficient in enhancing the activity than the cyano group. The level of activity also varied with the Af-substituent of the 4-carbamoyl group; a bulky alky] group provided the best combination of herbicidal activity against annual lowland weeds and excellent safety for transplanting rice. Introduction of a pair of electron-withdrawing groups at both ortho positions of the benzene ring at the 1 position of the imidazole ring enhanced the herbicidal activity significantly. Among the compounds synthesized, N-t-butyl-1-(2,6-dichlorophenyl)-5-(trifluoromethyl)imidazol-4-carboxamide, which showed good herbicidal activity against various annual lowland weeds and excellent safety for rice at a low dosage, is considered to be the most promising rice herbicide.
東海大学の論文

除草活性を有する新規イミダゾール-4-カルボキサミド誘導体の合成研究

スポンサーリンク

概要

著者

関連論文

スポンサーリンク