Investigation of Nitrogen- and Sulfur-containing Heterocycles. 53. Reactions of 5-Amino-6-mercaptopyrimidines with Derivatives of p-Chloronitrobenzene. Synthesis of a New Heterocyclic System - Pyrimido[4,5-b]-1,4-benzothiazepine

A series of pyrimidyl aryl sulfides was obtained from the reaction of 5-amino-6-mercaptopyrimidines with derivatives of p-chloronitrobenzene containing carbonyl functional groups. The properties of these sulfides and methods of their cyclization into derivatives of a new tricylic system, pyrimido[4,5-b]-1,4-benzothiazepine, were studied.