STRUCTURE-ACTIVITY RELATIONSHIP OF HERBICIDAL PYRAZOLE DERIVATIVES

摘要: Abstract The structure-activity correlations in herbicidal 1,3-dimethyl-4-benzoyl-5-hydroxypyrazole derivatives, which induce chlorosis by inhibiting biosynthesis of chlorophyll, were investigated. Data on activities against 7 species paddy weeds analyzed using pattern recongnition methods. SIMCA, multilinear least squares regression and adaptive classification methods employed. As descriptors for molecular features, van der Waals volume, hydrophilic electronic constants examined. It is shown that some correlation exists between pKa values measured potentiometric titration activities. structure 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-hydroxypyrazole has been finally selected as a moiety novel pre-emergence herbicide “pyrazolate” from the view point its high activity annual perennial with low phytotoxicity to rice plants.