Abstract
Many kinds of 1-substituted-2, 4, 5-trihaloimidazole derivatives were synthesized and their insecticidal action against the pyrethroid-resistant colony (O-colony) of the German cockroach, Blattella germanica, which showed cross-resistance to various pyrethroid insecticides, was investigated by means of topical application and by a heating fumigant method. Also studied was their acute oral toxicity to mice. A strong correlation was observed between the insecticidal activity to cockroaches and the toxicity to mice in most of these derivatives, however, between the two species, 1-(4-halobutyloxymethyl)-2, 4, 5-trichloroimidazoles showed a superior selective toxicity. Among these compounds, 1-(4-chlorobutyloxymethyl)-2, 4, 5-trichloroimidazole (S-377) was finally selected as the candidate compound for controlling the pyrethroid-resistant colony of German cockroaches, especially as heating fumigant agent. The insecticidal activity of S-377 against the O-colony was higher than that against susceptible strains by both the topical application and the heating fumigant method. Therefore, the S-377 is expected to be applicable in the practical field of controlling German cockroaches as a new active ingredient of insecticides.
