Design, synthesis, crystal structure and insecticidal evaluation of novel arylpyrazole derivatives containing cyhalothroyl thiourea moiety

Abstract

GRAPHICAL ABSTRACT ABSTRACT On the basis of the commercial insecticide Fipronil, a series of novel arylpyrazole derivatives containing the cyhalothroyl thiourea moiety were designed and synthesized via the key intermediate 5-amino-3-cyano-1-(substituted phenyl) pyrazole. The structures of target compounds were characterized by 1H NMR, FT-IR, elemental analysis and single crystal X-ray diffraction analysis. Their insecticidal activities against Culex pipiens and Musca domestica were evaluated. The results of bioassays indicated that title compounds exhibited satisfactory insecticidal activities. Among those, Compound 7t ((E)-3-(2-chloro- 3, 3, 3-trifluoroprop-1-en-1-yl)-N-((3-cyano-1-(2, 6- dichloro-4-(trifluoromethyl) phenyl)-1H-pyrazol-5-yl) carbamothioyl)- 2, 2-dimethyl cyclopropane carboxamide) exhibited the best insecticidal activities because of its lowest KT50 values, which are superior to the commercial insecticide Dextral tetramethrin and similar to Prallethrin. The type and position of substituent on the benzene ring played important roles on the biological activities of target compounds.