Chiral acidic amino acids as tethers for intramolecular glycosylation

Abstract

Intramolecular glycosylation with peptides as tethers is attractive for the synthesis of oligosaccharides because conjugation between the amino acids present in the tethers is facile. However, few studies have been published about the effects of the amino acid side chain length and amino acid chirality on the glycosylation process. In this study, we revealed that the chain length of the amino acid can regulate the regioselectivity of the glycosylation process based on our observation that the 1,2-linked products were preferred when tethers were those having aspartic acid residues linked to each other, while 1,3-linked products were preferred for glutamic acid-based tethers. However, the amino acid chirality was found to have no effect on the yield and stereoselectivity of the glycosylation reaction.

Graphical Abstract

Keywords:

• Aspartic acid
• glutamic acid
• intramolecular glycosylation
• peptide tether

Acknowledgments

The authors would like to thank Dr. Yukishige Ito (RIKEN and Osaka University) and Dr. Akihiro Ishiwata (RIKEN) for fruitful discussions and valuable suggestions. The authors thank Taylor & Francis Editing Services for the English language review.

Additional information

Funding

This work was partially supported by the Japan Society for the Promotion of Science (KAKENHI grant no. 16H06290 to Yukishige Ito and 21K05282 to Yoichi Takeda).