Synthesis and acaricidal activities of new 2-polyfluorophenylbenzazole derivatives

摘要

New 2-phenylbenzazole derivatives, thirteen benzoxazoles and eight benzothiazoles, were synthesized, and their acaricidal activities measured against the two-spotted spider mite (TSM). Some compounds with a polyfluorophenyl group were highly effective in killing the eggs (LC_(50) : < 50 ppm) with moderate activity (LC_(50):150-200 ppm) against the adults. Among them, 2-(3-chloro-2,4,5-trifluorophenyl)-5-methylbenzoxazole was selected as the most promising candidate for an acaricide, and the effects of its concentrate were evaluated. This formulation achieved a high rate of mortality in the citrus red mite and a kelthane-resistant strain of TSM in addition to a common strain of TSM.