Study On The Synthesis Of N-(2-pyrimidino) Benzamides With Biological Activities

Derivatived from N-phenylbenzamide, mepronil and flutoanil, which are widely used in agricultural plants' growth, have showed better effects on curing rice culm, sheath blight, powder mildew and leaf rust. In this article, 3-isopropoxyphenyl group in mepronil an flutoanil is replaced with 4-methyl-6-isopropoxy-2-pyrimidino group, three kinds of new N-(2-pyrimidino)benzamides' derivatives which haven't ever been reported have been prepared.First, 2-amino-4-methyl-6-hydroxypyrimidine is obstined from the reaction of ethyl acetoacetate and guanidine nitrate under the catalysting of sodium ethanol,the yield is 95%. 2-amino-4-methyl-6-chloropyrimidine is prepared from the following the reacting with phosphorus oxychloride, the yield is 70%. 2-amino-4-methyl-6-isopropoxypyrimidine is fromed from the reaction with isopropanol and sodoum,the yield is 80%. The structures of compounds was characterized by elemental analysis,IR and 1H-NMR analysis,which are consist with the expected structures.Then, three kinds of 2-substitued benzoyl chloride are obtained from the reaction of 2-bromobenzoic acid,2-nitrobenzoic acid and 2-methoxybenzoic acid with dichlorosulfoxide , the yields are over ninety percent.Finally, the target products are prepared from the reaction of 2-substitued benzoyl chloride with 2-amino-4-methyl-6-isopropoxypyrimidine under the catalyst of trithylamine,the yields are 55%,33%,48%. The effects of the reaction conditions on the yield were investigated and reacting conditions optimized.The result shows that the yield is highest when the reaction time is 4~5 hours at 30℃.The structures of title compounds was characterized by elemental analysis,IR and 1H-NMR analysis,which are consist with the expected structures.