Synthesis and Biological Activities of Novel Pyrazole Oxime Derivatives Bearing an Oxazole Moiety

Abstract

In search of novel pyrazole oximes with good biological activities, twenty pyrazole oxime compounds were prepared by introducing an oxazole unit into pyrazole oxime based on the structure of fenpyroximate. The structures of the target compounds were confirmed by 1 H NMR, 13 C NMR and elemental analysis. Preliminary bioassay displayed that some target compounds had wonderful insecticidal activities against Oriental armyworm or Aphis medicaginis at the concentrations of 500 and 100 μg/mL. At the concentration of 100 μg/mL, 5- 9s) showed 100% mortality rate against Oriental armyworm, and 5-(4-bromophenoxy)-1,3-dimethyl-1H-pyrazole-4-formyl-O-((5-(4-fluorophenyl)oxazol-2-yl)methyl)oxime (9g) and 9s exhibited 100% insecticidal property against Aphis medicaginis. Additionally, compound 9s possessed 70% insecticidal activity against Tetranychus cinnabarinus at 500 μg/mL.

Recent Research Progress in Oxime Insecticides and Perspectives for the Future

“…45 In the same year, Dai also synthesis a series of novel pyrazole oxime derivatives by introducing substituted oxazole structures into pyrazole oxime. 46 Partial compounds exhibited remarkable insecticidal activity against O. armyworm or A. medicaginis, with compound 44 (Figure 6J) demonstrating 100% insecticidal activity against O. armyworm and A. medicaginis at 100 μg/mL. Furthermore, the control effect of compound 44 against T. cinnabarinus was 70% at 500 μg/mL.…”

“…Pyrazoloxime ether compound 43 (Figure I) with a 1,3,4-oxadiazole ring showed 100% insecticidal activity against O. armyworm and A. medicaginis at 100 μg/mL . In the same year, Dai also synthesis a series of novel pyrazole oxime derivatives by introducing substituted oxazole structures into pyrazole oxime . Partial compounds exhibited remarkable insecticidal activity against O. armyworm or A. medicaginis , with compound 44 (Figure J) demonstrating 100% insecticidal activity against O. armyworm and A. medicaginis at 100 μg/mL.…”