Synthesis and Insecticidal Activities of Novel Pyrazole Oxime Ethers Carrying 1,3,4-Oxadiazole Unit

In search of novel pyrazole oxime ether derivatives with potent bioactivities, fifteen new pyrazole oxime ethers were designed and synthesized by introducing 1,3,4-oxadiazole moiety into the C-4 position of pyrazole based on the structure of fenpyroximate. Their structures were confirmed by H-1 NMR, C-13 NMR and elemental analysis. Preliminary bioassay data showed that some title compounds possessed good insecticidal activities against Oriental armyworm or Aphis medicaginis at the concentration of 500 and 100 mu g/mL. At 100 mu g/mL, compounds 10a, 10e, 10f and 10j displayed 100% mortality rate against Oriental armyworm, and compounds 10g, 10j and 10l showed insecticidal activity against Aphis medicaginis with 100%. In addition, compound 10l had 100% mortality rate against Tetranychus cinnabarinus at 500 mu g/mL.