Sulfur-containing Pyridine Derivatives. XLIII.¹⁾Synthesis of Pyrido[2, 3 : 2', 3']-p-thiazines. (2)

Abstract

1) Synthesis of derivatives of 6-chloropyrido[2, 3 : 2', 3']-p-thiazine, 5'-oxo-5', 6'-dihydropyrido[2, 3 : 2', 3']-p-thiazine, pyrido[3, 4 : 3', 2']-p-thiazine, and 2-azaphenothiazine was described. 2) Some of their chemical properties, especially their behavior to acids and alkalis, were investigated. 3) The reaction using 2-mercapto-3-amino-6-chloropyridine as one of the starting materials often afforded the by-product of orange rhombics, m.p.210°, which was proved to be 3, 3'-diamino-6, 6'-dichlorodipyridyl 2, 2'-disulfide.