Catalytic stereospecific O-glycosylation
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark. cmp@chem.ku.dk.
Chemical Communications (Cambridge, England)
|January 27, 2017
Summary
A novel catalytic method activates trichloroacetimidate donors for O-glycosylation, proceeding with stereospecific inversion. This efficient protocol broadens glycosylation strategies for carbohydrate chemistry.
Area of Science:
- Carbohydrate Chemistry
- Organic Synthesis
- Catalysis
Background:
- O-glycosylation is crucial for synthesizing complex carbohydrates.
- Efficient activation of glycosyl donors remains a challenge in carbohydrate chemistry.
Purpose of the Study:
- To develop a simple and efficient protocol for activating trichloroacetimidate donors.
- To investigate the stereochemical outcome of the O-glycosylation reaction.
Main Methods:
- Utilized TMSNTf2 or Tf2NH as catalysts for trichloroacetimidate activation.
- Performed O-glycosylation reactions with various glycosyl donors and acceptors.
- Analyzed the stereochemical outcome of the reactions.
Main Results:
- Developed a straightforward catalytic protocol for O-glycosylation.
- Demonstrated stereospecific inversion of the glycosyl donor configuration.
- Showcased the protocol's applicability with common glycosyl donors and simple alcohols/sugar acceptors.
Conclusions:
- The new protocol offers a simple and effective method for O-glycosylation.
- The reaction proceeds with predictable stereochemical inversion, valuable for targeted synthesis.
- This method expands the toolkit for constructing glycosidic linkages.
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