Substituted hydrazides of hydroxy carboxylic acids

Under the action of concentrated sulfuric acid, a series of -alkyl--arylhydrazides of diarylglycolic acids is converted into 1-alkyl-1,2,3,4-tetrahydrocinnolin-3-ones. The reaction takes place through the intermediate formation of a halochromic salt.For Communication LXV, see 1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 844–846, June, 1970.