Containing Substituted Pyrimidine Ring 2,4 - Dichlorophenoxyacetic Propionamide And The Propionyl Thiourea Derivatives And Their Biological Activity

Eight N-(4,6-disubstituedpyrimidin-2-yl)-2-(2,4-dichlorophenoxy)propionamide and five 2-(2,4-Dichlorophenoxy)propionylthioureas were synthesized from correspo- nding 2-(2,4-dichlorophenoxy)propionic acid, through three steps and four steps respectively. Five N-(5,7-disubstituted 2H- [1,2,4]thiadiazolo[2,3-a]pyrimidin -2– yl- iden)-(2,4-dichlorophenoxy)acetamide were prepared by oxidizing cyclization of N' -(4,6-disubstituted-pyrimid-2-yl) - N-[2-(2,4-dichlorophenoxypropionyl)] thiourea. All of these target compounds are new compounds and their structures were con- firmed by IR, 1H NMR(13C N- MR) ,MSand elemental analysis. Their physical prop- erties, spectrum properties, reaction conditions and synthesized methods were dis- cussed as well. The structural formulas of the title compounds (Ⅰ) ,(Ⅱ), (Ⅲ)are as follows respectively:In order to investigate the relationship between the structure of compounds and its property. Compound 5-tert-butyl-1-[2-(2,4-dichlorophenoxy)propionyl]thiobiurea and (Ⅰa),(Ⅱb),(Ⅲd) were successfully prepared , their crystal structures were determined by single crystal X-Ray diffraction analysis. And we had some discussion on their structures and activities.The preliminary biological activities tests of target compounds were all finished in Shanghai Branch of National Pesticide R&D South Central. The preliminary herbicidal tests show that most of the compounds were found to be highly effective in inhibitory activities against selected weeds. The some title compounds also showed selective inhibitory activities against monocotyledon plant and dicotyledon plant. In addition, there are potentially applied value for some compounds.