Synthesis, insecticidal and acaricidal activities of novel 2-arylpyrroles

To search for novel 2-arylpyrroles with unique biological activities, a series of novel 2-arylpyrrole derivatives were designed and synthesized, and their structures were characterized by ¹H and ¹³C NMR spectroscopy, MS spectrometry, and elemental analysis. Their insecticidal activities against Lepidopteran pests (e.g. Mythimna separata) and acaricidal activities against mites (e.g. Tetranychus urticae) were evaluated. The results of bioassays indicate that some of these title compounds exhibited excellent insecticidal and acaricidal activities. For example, 4-bromo-1-((chloromethoxy)methyl)-2-(4-chloro phenyl)-5-(trifluoromethyl)pyrrole-3-carbonitrile (6a), 4-bromo-2-(4-chlorophenyl)-1-((2-fluoroethoxy)-methyl)-5-(trifluoromethyl)pyrrole-3-carbonitrile (6d) showed insecticidal activity against Mythimna separata and 4-bromo-2-(4-chlorophenyl)-1-((isopropoxymethoxy)methyl)-5-(trifluoro methyl)pyrrole-3-carbonitrile (7d) showed acaricidal activity against Tetranychus urticae. They were more effective than Chlorfenapyr, which has been the only commercialized member of a new class of chemicals of 2-arylpyrroles.