The synthesis of thieno[2,3-d]pyrimidine nucleosides related to the naturally occurring nucleosides cytidine and uridine

Abstract

Several ribofuranosyl nucleosides of the thieno[2,3-d]pyrimidine ring system have been prepared by condensation of the persilylated base with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose in 1,2-dichloroethane in the presence of stannic chloride. These nucleosides are analogues of uridine and cytidine. The synthesis of the arabinofuranosides of 4-aminothieno[2,3-d]pyrimidin-2-one and 4-amino-5-methylthieno[2,3,d]pyrimidin-2-one from a cyclonucleoside intermediate is described.