Approaches to stereoselective 1,1'-glycosylation.

Area of Science:

• Carbohydrate Chemistry
• Glycobiology
• Organic Synthesis

Background:

• Nonreducing disaccharides are key components in various biological molecules, including mycobacterial glycans and pathogen-associated molecular patterns (PAMPs).
• These disaccharides play vital roles in host-pathogen interactions, cellular signaling, and disease development.
• Isolation from natural sources often yields impure or degraded products, necessitating synthetic approaches.

Purpose of the Study:

• To review recent advancements in 1,1 -glycosylation strategies for synthesizing nonreducing disaccharides.
• To highlight the challenges and importance of stereoselective synthesis of 1,1 -linked disaccharides.
• To discuss applications in vaccine research, therapeutics, and diagnostics.

Main Methods:

• Overview of selected 1,1 -glycosylation strategies.
• Discussion of methods for forming α,β-, β,β-, and α,α-1,1 -glycosidic linkages.
• Focus on stereoselectivity challenges, particularly with lactol glycosyl acceptors.

Main Results:

• Recent advances in 1,1 -glycosylation have been highlighted.
• Various strategies for forming different stereoisomers of 1,1 -linked disaccharides are presented.
• The inherent difficulties in controlling stereochemistry at two anomeric centers are emphasized.

Conclusions:

• Robust and stereoselective synthetic strategies are essential for producing complex 1,1 -disaccharide-containing biomolecules.
• Overcoming challenges in 1,1 -glycosylation is critical for advancing vaccine development and therapeutic applications.
• Further research into stereoselective glycosylation, especially with challenging acceptors, is warranted.