Isothiourea - catalyzed α-selective glycosylations
Bhaswati Ghosh1, Charles Enlow1, Zhichen Ma1
1Department of Chemistry Purdue University, 720 Clinic Drive, West Lafayette, IN 47906, USA. aaxelro@purdue.edu.
Chemical Communications (Cambridge, England)
|February 12, 2025
Summary
A new catalytic method efficiently creates α-1,2-glycosyl linkages in both cis and trans configurations. This strategy utilizes readily available HyperBTM isothiourea for glycosyl bromide and chloride donors, achieving high yields and selectivity.
Area of Science:
- Carbohydrate Chemistry
- Organic Synthesis
- Catalysis
Background:
- Glycosyl linkages are fundamental in biological systems and drug development.
- Controlling stereochemistry during glycosidic bond formation remains a significant challenge in carbohydrate synthesis.
Purpose of the Study:
- To develop a novel catalytic strategy for the efficient synthesis of α-1,2-glycosyl linkages.
- To achieve control over both cis and trans stereochemical outcomes in glycosylation reactions.
Main Methods:
- Utilizing commercially available HyperBTM isothiourea as a catalyst.
- Employing glycosyl bromide and glycosyl chloride as donors.
- Optimizing reaction conditions for yield and stereoselectivity.
Main Results:
- Successful formation of α-1,2-glycosyl linkages with high yields.
- Demonstrated ability to selectively produce both α-1,2-cis and α-1,2-trans isomers.
- The catalytic system proved effective with both bromide and chloride glycosyl donors.
Conclusions:
- The presented catalytic strategy offers an efficient and selective method for synthesizing α-1,2-glycosyl linkages.
- HyperBTM isothiourea is a versatile catalyst for stereoselective glycosylation.
- This approach provides a valuable tool for carbohydrate chemists and drug discovery efforts.
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