Fused Heterocycles. Part I. Synthesis of Some Annelated 1,2,4-Triazole Systems from [4-(1 H -Benzimidazol-2-yl)-Phthalazin-1-Yl]Hydrazine

Abstract

Substituted 6-(1H-benzimidazol-2-yl)-[1,2,4]triazolo[3,4-a]phthalazine derivatives containing alkyl, aryl, hydroxyl, mercapto, methylthio and formyl substituents at position 3 have been synthesised. Di-[6-(1H-benzimidazol-2-yl)-3-[1,2,4]triazolo[3,4-a]phthalazin-3-yl]alkanes have been obtained by the use of dicarboxylic acids or their esters in the above condensations. Methylation reactions of the triazolo-phthalazine system are reported.