High yield synthesis of 4H-1,4-benzothiazine-1,1-dioxide derivatives

DE MONTIS S;FATTUONI, CLAUDIA;CADONI, ENZO;CABIDDU, MARIA GRAZIA;USAI, MICHELE;CABIDDU S.

2008-01-01

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Abstract

4H-1,4-Benzothiazine-1,1-dioxide derivatives were synthesized through a sequence of almost quantitative reactions. The commercial starting material 2-(methylsulfanyl)aniline was Boc-protected, N-acylated and oxidized at the sulfur atom to obtain a sulfonyl derivative. An anionic transposition of the acyl group followed by a simultaneous deprotection-cyclization gave the title products in excellent yields. All products and intermediates were fully characterized.