Investigation of nitrogen- and sulfur-containing heterocycles

The synthesis of two-ring 1,4-thiazine systems was previously accomplished on the basis of the reaction of o-amino mercapto derivatives of pyridine and pyrimidine with dicarbonyl compounds — halo -keto esters and halo -diketones. In the present paper it is shown that the primary products of this reaction are S--keto-alkylmercapto derivatives, which are subsequently cyclized to the corresponding hydroxy amino compounds. The latter are converted to N-acylamino-S--carbethoxy (keto)alkylmercapto derivatives under the influence of an alkaline agent. The indicated compounds were isolated and characterized 2, 3].See 1] for communication 36.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 250–253, February, 1979.