Shtyl N. Synthesis of 2-heteroaryl- and 2-spiro derivatives of 1,4-benzothiazin-3-ones based on the reaction of 2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazines with C-nucleophiles

The dissertation is devoted to the development of the methods of synthesis of 2-heteroaryl- and 2-spiro derivatives of 1,4-benzothiazin-3-ones with C-nucleophiles. The reaction of 2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazines with ?-excessive heterocycles was investigated. Based on the reaction a new synthetic approach to 2-heteroaryl-3-oxo-3,4-dihydro-2H-1,4-benzothiazines was developed. It was shown that spiro[1,4-benzothiazine-2,5'-pyrrolo[2,3-d]pyrimidines was formed on the reaction with 6-aminouracils. The reactions of 2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazines with enamines were studied for the first time. It was shown that disregarding the structure of the enamines the reaction occurs at the beta-carbon atom. For the first time the enamines containing terminal double bond were isolated as individual compounds. We discovered a non-trivial ring-expansion rearrangement of 2-ethyl-3-(methylimino)-2(3-oxo-3,4-dihydro-2H-1,4-benzothizin-2-yl)butanoate affording ethyl 11-ethyl-2,3-dimethyl-4-oxo-2,3,4,5-tetrahydro-1H-2,5-methano-6,1,3-benzothiadiazocine-11-carboxylate.Use of 2-substituted 1,4-benzothiazin-3-ones in the synthesis of 2-spiro and 2-hetarylderivatives of 1,4-benzothizin-3-ones was investigated