The Convergent Synthesis of [1, 3]-Thiazino[2, 3-f]-Theophylline and [1, 3]-Thiazino[3, 2-e] Theophxlline Ring Systems

Abstract

A preparative useful route to ethyl 1,2,3,4-7,8-hexahydro-1,3-dimethyl-2,4-dioxo-6H-[1,3]-thiazino [2,3-f]-purine-8-carboxylate and its [3,2-e] isomer by base-promoted cyclization of corresponding {[2-(p-toluenesulfonyl-oxy)ethyl]theopbyllin-8-yl)thioglycolates is described.