Thio-sugars. Part 3. 4-Thiotetrofuranose nucleosides

Abstract

Nucleosides have been prepared for biological testing with 6-substituted purines, theophylline, and 5-substituted uracils as bases and 4-thio-DL-erythrofuranose and 4-thio-DL-threofuranose as sugars. 1-O-Acetyl-4-thioerythrofuranose 2,3-phenylboronate has again proved a valuable synthetic intermediate, yielding under mild conditions the purine nucleoside esters in the presence of toluene-p-sulphonic acid and the pyrimidine compounds from the silylated bases with tin(IV) chloride. The corresponding 2,3-dibenzoates of both sugars were also used, but in all cases the uracil N³-nucleosides were obtained.