634182-14-2Relevant academic research and scientific papers
Efficient Synthesis of S-linked Glycopeptides in Aqueous Solution by a Convergent Strategy
Zhu, Xiangming,Schmidt, Richard R.
, p. 875 - 887 (2007/10/03)
In naturally occurring glycopeptides and glycoproteins the glycan residues generally possess N- and O-linkages to the peptide backbone. Here we report the synthesis of the corresponding S-linked glycopeptides by a convergent strategy to provide compounds which should be quite stable to glycosidases. To this end, peptides that contain β-bromoalanine and γ-bromohomoalanine were generated either directly by bromination of serine and homoserine residues, respectively, or by standard ligation of the corresponding amino acids. 1-Thiosugars of O-acetyl protected GalNAc, GlcNAc, and lactose were prepared by known procedures. Reaction of the thiosugars with these peptides in an ethyl acetate/water two-phase system, which contained TBAHS and NaHCO3, or in a one-phase system that consists of DMF/water and which contains NaHCO 3, led to the desired S-linked glycopeptides cleanly and in almost quantitative yield. This reaction also worked well for O-unprotected 1-thiosugars.
