Synthesis of 2-substituted cinchoninic acid amides and their cyclization into 1,2,4-triazolo[4,3-a]-quinoline-9- and 1,2,4-triazino[4,3-a]quinoline-10-carboxylic acid amides

Substituted amides of 2-hydrazino- and 2-ethylhydrazinocinchoninic acids react with pyruvic acid and its ethyl ester to give amides of 3-methyl-4-oxo-1,2,4-triazino[4,3-a]quinoline-10-carboxylic acid. On reaction with aromatic aldehydes they are converted into amides of 2-ethyl-3-phenyl-2,3-dihydro-1,2,4-triazolo[4,3-a]quinoline-9-carboxylic acid, or, in the case of unsubstituted hydrazines, into amides of 2-arylidenehydrazinocinchoninic acid, which was oxidized to substituted 1,2,4-triazolo[4,3-a]quinolines. ©1997 Plenum Publishing Corporation.