DESIGN,SYNTHESES AND BIOLOGICAL ACTIVITY OF NOVEL HERBICIDES TARGETED ALS (X)QUANTITATIVE STRUCTURE ACTIVITY RELATIONSHIPS OF SULFONYLUREA AND TRIAZOLOPYRIMIDINE SULFONAMIDE HERBICIDES

The quantitative relationship between the structure of 20 sulfonylureas and 16 sulfonamides and their herbicidal activity against rape were analyzed using Hansch approach. The results showed that the structure activity relationships of the two sets of compounds were identical, which suggested that they might act on the same target site. The electronic properties of the molecules are dominant factor to the activity and there is apparently an optimum electronic property (Σσ or pKa) for the molecules to fit the receptor.