The reaction of cyanoacetylhydrazine with ω-bromoacetophenone:: Novel synthesis of 1,3,4-oxadiazine, pyridazine and coumarin derivatives

The reaction of cyanoacetylhydrazine with omega-bromoacetophenone gave the condensation product beta-Bromoacetophenone-alpha-cyanoacetylhydrazone (3). The latter product underwent ready cyclization to give the 1,3,4-oxadiazine derivative 4. The reactivities of either 3 or 4 towards some chemical reagents like cyanomethylene reagents, diazonium salts, aromatic aldehydes, phenylisothio-cyanate and elemental sulfur were studied to afford 17 newly products for which the toxicity towards Fusarizan oxysporum f. sp. Lycopersici and Helminthosporium oryzea was measured. Moreover their effect towards mycelial dry mass, sporulation and nucleic acid synthesis of Fusarium oxysporum f. sp. Lycopersici was measured.