Using
line-library/content/render" xmlns:mml="http://www.w3.org/1998/Math/MathML" id="jhet2640-eo-0002">3-(4-cyano phenoxy)-6-methyl-4-(3-trifluoromethylphenyl) pyridazine (compound
) as a leading compound, a total of 24 novel 3-(substituted phenoxy)-6-methyl-4-(3-trifluoromethylphenyl) pyridazine derivatives containing two electron-withdrawing groups on the benzene ring (acylamine and oxime ether) were synthesized. Their herbicidal, insecticidal activities were bioassayed, and the herbicidal activity of compound
against
Brassica campestris was 97.6% at 300 g/ha, which was better than the commercial herbicide
line-library/content/render" xmlns:mml="http://www.w3.org/1998/Math/MathML" id="jhet2640-eo-2001">diflufenican at the this concentration and is equal to the activity of the leading compound
. Compound
,
,
, and
displayed excellent insecticidal activity against
Aphis laburni Kaltenbach (>95%). The results show that the oxime ether substitutions exhibit better bleaching and herbicidal activity than the acylamine ones. The bleaching and herbicidal activity of
para-position substitutions is better than the
meta-position ones. It seems that the
para-position on the benzene ring of oxime ether pyridazine derivatives is one of the key active sites that affect their herbicidal activities.
