Aziridine ring opening as regio- and stereoselective access to O-glycosyl amino acids and their transformation into O-glycopeptide mimetics

Abstract

Glycosyl amino acid mimetics of the typical GalNAc-(1→ O)-Ser/Thr motif of O-glycopeptides were synthesised. Starting from galactose a 1,5-anhydro derivative could be obtained and regio- and stereoselectively coupled to serine- or threonine-derived aziridine compounds, respectively. The corresponding Fmoc derivatives could be used to prepare two 13-mer glycopeptides of the mucin MUC1 carrying instead of Ser-2 or Th-5, the corresponding O-glcycosyl amino acid mimetics.