Straightforward entry to s-glycosylated fmoc-amino acids and their application to solid phase synthesis of glycopeptides and glycopeptidomimetics

Streamlined access to S-glycosylated Fmocamino
acids was developed. The process provides diverse
glycosylated modified amino acids in high yield and stereoselectivity
taking advantage of the in situ generation of a
glycosylthiolate obtained from carbohydrate acetates in a few
steps. Mild basic conditions make the conjugation reaction
compatible with Fmoc-iodo-amino acids. To validate the
strategy the glycosylated building blocks were used for SPPS
and the unprecedented incorporation of a long thiooligosaccharide
to the peptide chain was demonstrated.