Effective and chemoselective glycosylations using 2,3-unsaturated sugars
Shunichi Kusumi1, Kaname Sasaki, Sainan Wang
1Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Organic & Biomolecular Chemistry
|May 28, 2010
Summary
Researchers developed novel 2,3-unsaturated glycosyl acetates for efficient deoxyoligosaccharide synthesis. These compounds exhibit enhanced reactivity, enabling the creation of complex carbohydrates and O-glycosides.
Area of Science:
- Carbohydrate Chemistry
- Organic Synthesis
- Glycobiology
Background:
- Mimicking lysozyme-initiated hydrolysis of mucopolysaccharides.
- Investigating the reactivity of 2,3-unsaturated glycosyl acetates.
- Exploring glycosylation mechanisms for deoxyoligosaccharide synthesis.
Purpose of the Study:
- To design and synthesize novel glycosyl donors with a C2-C3 double bond.
- To evaluate the reactivity of these donors in glycosylation reactions.
- To achieve chemoselective synthesis of deoxyoligosaccharides and O-glycosides.
Main Methods:
- Design of glycosyl donors mimicking lysozyme reaction mechanisms.
- Comparative reactivity studies of various glycosyl acetates under different conditions.
- Application of combinatorial techniques for short-step synthesis.
Main Results:
- 2,3-unsaturated glycosyl acetates showed significantly higher reactivity than saturated counterparts.
- 2,3-unsaturated-4-keto glycosyl acetates exhibited much lower reactivity.
- Effective chemoselective glycosylations were achieved, constructing various deoxyoligosaccharides.
- Highly reactive unsaturated glycosyl acetates proved useful for synthesizing O-glycosides of tertiary alcohols.
Conclusions:
- Novel 2,3-unsaturated glycosyl acetates are effective glycosyl donors.
- These donors enable efficient and chemoselective synthesis of deoxyoligosaccharides.
- The methodology extends to the synthesis of O-glycosides with challenging alcohol substrates.
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