Quantitative Structure-Activity Relationships of the Herbicidal N-Benzylbutanamides against Cyperus rotundus

Herbicidal Activity of N-Benzylbutanamides (Part IV)

Abstract

The herbicidal activity of 45 N-benzylbutanamides against Cyperus rotundas was determined by the pot test with pre-plant soil incorporation method. The variation in the activity of N-(1-methyl-1-phenylethyl)-substituted acetamides was shown by the Hansch analysis to be related with the variation in the steric bulkiness of the substituent. The haloalkyl substituent was detrimental to the activity. Among the N-(1-methyl-1-phenylethyl)-2-ethyl-3, 3-dimethylbutanamides having various substituents on the benzene ring, 4-methylphenyl derivative exhibited the highest activity.