Isao Ohno

Quantitative structure-activity relationships of phenyl N-methylcarbamates against the smaller brown planthopper and its acetylcholinesterase

Abstract Insecticidal activity against smaller brown planthoppers and inhibitory activity against their acetylcholinesterase preparation were determined for a number of mono- and polysubstituted phenyl N-methylcarbamates. The indices of these activities were analyzed by means of free-energy-related substituent parameters and regression analysis. The mechanism of the inhibition reaction with the AChE preparation was shown to be quite similar but not entirely identical to those proposed earlier for reactions with bovine erythrocyte and fly-head enzyme preparations. The synergized insecticidal activity was found to closely correspond to the anti-AChE activity except for the o-isomers.

Synthesis of some novel carboxylic acids and insecticidal activity of their esters.

Various novel acyclic carboxylic acids were prepared and some of their 3-phenoxybenzyl esters were found to have slight insecticidal activity.