Collect. Czech. Chem. Commun. 1986, 51, 1133-1139

The synthesis of substituted 2H-1,2-benzothiazines 1,1-dioxides

Jiří Svoboda, Jaroslav Paleček and Václav Dědek

Department of Organic Chemistry, Institute of Chemical Technology, 166 28 Prague 6


The base-catalyzed rearrangement of the esters of 2H-1,2-benzothiazolin-3-one-2-acetate 1,1-dioxide (IIa - IIc) afforded substituted 2H-1,2-benzothiazine-3-carboxylate 1,1-dioxides IIIa -IIIc. After N-alkylation and aminolysis the antiinflammatory drugs piroxicam and isoxicam were obtained.