Synthesis And Herbicidal Activity Of [1,2,4]Triazolo[1,5-a]Pyrimidine-2-Sulfonamide Derivatives

The research progress of herbicides, especially for famous ALS inhibitor, Sulfonamides and Flumetsulam,was reviewd in this thesis.Using Flumetsulam as the lead structure,three series of compound to explore novel derivatives of pyrimidinylethers containing heterocycles which have higher biological activity,have been synthesized via analogue synthesis method.The structures of the target compounds have been confirmed by ~1HNMR and Element Analysis,which can be devided into three series according to their structures categories, shown as follows:1. N-(aryl)-5-methyl-1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamide (I)2. N-(aryl)- 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamide (II)3. N-(2,6-difluorophenyl)-5,6,7-substituent-1,2,4-triazolo[1,5-a]pyrimidine-2-sulfona -mide (III)The herbicidal activity of compounds synthesized were tested. In addition,we improved the synthesis method of Flumetsulam.The yield of this raction was increased to about 75%.