A Short Route to the Synthesis of Digoxose Trisaccharide Glycal Donor via Mislow–Evans Rearrangement

The Mislow–Evans rearrangement
was used as a key
reaction
to construct digitoxose-derived glycals. The same rearrangement was
iteratively performed on di- and trisaccharides to form the digoxose
glycal donor component present in the cardenolides digitoxin, digoxin,
and gitoxin. The scalability of the trisaccharide synthesis was shown
by performing the reactions on a multigram scale. Glycosylation reactions
were also performed between the synthesized digoxin glycal donor and
aglycons digoxigenin and gitoxigenin to synthesize novel cardenolide
derivatives.