Synthesis and Acaricidal Activities of New Benzophenone O-Methyloximes

Abstract

We synthesized newly developed benzophenone O-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-2-pyridyloxymethyl 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 O-methyloxime (21) showed the most potent activity against Tetranychus urticae and Tetranychus kanzawai.