The detailed practical synthesis of 4'-thionucleosides starting from L-arabinose is described here. 1,4-Anhydro-2,3-O-isopropylidene-4-thioribitol, which is the key intermediate for the synthesis of 4'-thionucleosides, is obtained from L-arabinose in several steps, including a novel reductive ring-contraction reaction. After oxidation of the key intermediate, the sulfoxide is subjected to Pummerer-type thioglycosylation in the presence of persilylated nucleobases to obtain the 4'-thioribonucleosides in good yield and β-selectively. © 2017 by John Wiley & Sons, Inc.
Keywords: 4-thioribonucleosides; 4-thiosugar; L-arabinose; Pummerer reaction; reductive ring contraction.
Copyright © 2017 John Wiley & Sons, Inc.