in good yields by regiospecific 1,3-dipolar cycloadditionreactions between aromatic nitrile oxides, generated in situfrom the corresponding hydroxyimidoyl chlorides, with non-symmetrical activated alkynes in the presence of catalytic amounts of copper(I) iodide. Effects of 3,5-disubstituted isoxazoles on nitric oxide and reactive oxygen speciesgeneration in Arabidopsis tissues was studied using specific