Light-Driven Site-Selective Glycosylation of Native Carbohydrates

Area of Science:

• Carbohydrate Chemistry
• Organic Synthesis
• Photocatalysis

Background:

• Carbohydrates are abundant but challenging to synthetically modify due to oxygen functionalities.
• Site- and stereoselective modification of native sugars is a key goal in glycochemistry.
• Protecting group strategies often complicate carbohydrate synthesis.

Purpose of the Study:

• To develop a method for site- and stereoselective C-glycosylation of native sugars.
• To bypass the need for protecting groups in carbohydrate modification.
• To enable efficient synthesis of complex saccharides and protein modifications.

Main Methods:

• Utilized photocatalysis for selective activation of native sugars.
• Developed a "cap and glycosylate" approach.
• Employed direct radical functionalization of in situ formed thioglycosides.

Main Results:

• Achieved site- and stereoselective C-glycosylation of unprotected carbohydrates.
• Enabled the synthesis of complex saccharide structures.
• Facilitated post-translational modification of proteins.

Conclusions:

• Photocatalysis offers a powerful strategy for simplifying carbohydrate synthesis.
• The "cap and glycosylate" approach advances glycochemistry research.
• This method has broad implications for synthesizing complex carbohydrates and modifying proteins.