Selective synthesis and comparative activity of olefinic isomers of 1,2-benzothiazine-1,1-dioxide carboxylates as aldose reductase inhibitors

Article abstract of DOI:10.1039/c4ra01016g

α,β- and β,γ-unsaturated carboxylate isomers of 1,2-benzothiazine-1,1-dioxide were selectively synthesized via the Wittig olefination reaction under various temperature conditions. At 40 °C, α,β-unsaturated esters with high Z-stereoselectivity (83-87%) we