Synthesis and Acaricidal Activities of New Benzophenone <i>O</i>-Methyloximes

Abstract

We synthesized newly developed benzophenone 0-methyloxime derivatives (I) and assessed their acaricidal activities. Studies of the structure-activity relationship revealed that the strongest acaricidal activity was achieved when position-2 in the left phenyl moiety was substituted with a 5-trifluoromethyl-2pyridyloxymethyl group. Among the geometrical isomers at the oxime moiety, the Z-isomers were more active than the E-isomers. When the right phenyl moiety was substituted with a 4'-chloro, 4'-bromo or 4'-trifluoromethyl group, good acaricidal activity was obtained. Among the compounds examined, 4'-chloro-2-(5-trifluoromethyl-2-pyridyloxymethyl)benzophenone 0-methyloxime (21) showed the most potent activity against Tetranychus urticae and Tetranychus kanzawai.