Synthesis of fused pyrimidines with <i>N</i>‐, <i>S</i>‐heterocyclic moieties by double‐annelation reaction

Abstract

Abstract A variety of tri‐ and tetracyclic hetero systems were obtained by reaction of heteroaromatic ortho ‐aminoesters or ortho ‐aminonitriles with iminothioether, yielding double‐annelation of a thiazolo[3,2‐a]‐pyrimidine, pyrimido[2,l‐b]thiazine, imidazo[1,2‐a]pyrimidine, and pyrimido[1,2‐a]pyrimidine moieties in a one‐pot process.