Regioselective modification of unprotected glycosides
Manuel Jäger1, Adriaan J Minnaard1
1Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands. a.j.minnaard@rug.nl.
Chemical Communications (Cambridge, England)
|November 17, 2015
Summary
Developing selective carbohydrate modification methods is crucial for efficient synthesis. This review highlights novel transition metal and organocatalysis approaches for regioselective and chemoselective carbohydrate transformations.
Area of Science:
- Organic Chemistry
- Carbohydrate Chemistry
- Synthetic Chemistry
Background:
- Selective modification of unprotected carbohydrates is challenging due to the similar reactivity of hydroxyl groups.
- Existing synthetic routes often involve multiple steps, increasing complexity and reducing efficiency in carbohydrate synthesis.
Purpose of the Study:
- To review and discuss methods for regioselective and chemoselective carbohydrate modification.
- To focus on novel approaches utilizing transition metal catalysis and organocatalysis.
- To identify challenges and opportunities in the field of selective carbohydrate modification.
Main Methods:
- Review of literature focusing on transition metal-catalyzed reactions for carbohydrate modification.
- Analysis of organocatalysis strategies for achieving regioselectivity and chemoselectivity.
- Discussion of recent advancements and emerging trends in selective carbohydrate functionalization.
Main Results:
- Novel catalytic methods offer improved selectivity in carbohydrate modification.
- Transition metal catalysis and organocatalysis provide powerful tools for regioselective and chemoselective transformations.
- These approaches can potentially streamline synthetic routes and reduce the number of steps required.
Conclusions:
- Selective carbohydrate modification is essential for advancing carbohydrate chemistry.
- Catalytic methods, particularly transition metal and organocatalysis, represent promising avenues for future research.
- Further development is needed to overcome existing challenges and fully exploit the potential of these techniques.
Related Concept Videos
01:24Oligosaccharide Assembly
3.8K
Protein glycosylation starts in the ER lumen and continues in the Golgi apparatus. Glycosyltransferases catalyze the addition of sugar molecules or glycosylation of proteins. Usually, these enzymes add sugars to the hydroxyl groups of selected serine or threonine residues to form O-linked glycans or the amino groups of asparagine residues to form N-linked glycans. Different positions on the same polypeptide chain can contain differently linked glycans.
Multiple sugar molecules that may or may...
Multiple sugar molecules that may or may...
3.8K
01:23Protecting Groups for Aldehydes and Ketones: Introduction
9.5K
Protecting groups are compounds that can bind to a specific functional group in the presence of other functional groups to protect them from undesired chemical reactions. These compounds can selectively bind to particular functional groups and advance chemoselective reactions in polyfunctional systems (Figure 1). After the functional group has served its purpose, it is removed by reacting it with specific compounds.
9.5K
02:35Regioselectivity of Electrophilic Additions-Peroxide Effect
11.6K
In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
11.6K
01:14Drug Metabolism: Phase II Reactions
5.6K
Phase II reactions are essential for the detoxification and elimination of drugs from the body. These reactions involve the conjugation of parent drugs or their phase I metabolites with endogenous molecules, resulting in more hydrophilic drug conjugates. The primary conjugation reactions in this phase are sulfation and glucuronidation. Both sulfation and glucuronidation typically produce biologically inactive metabolites. However, in some cases involving prodrugs, active metabolites may be...
5.6K
01:33Regioselective Formation of Enolates
3.7K
As depicted in the figure below, the unsymmetrical ketones can form two possible enolates: less substituted or more substituted enolates. Usually, the thermodynamic enolates are formed from the more substituted α-carbon atom, while the kinetic enolates are formed faster by deprotonation from the less substituted position. The thermodynamic enolates have lower energy, so they are more stable. But the energy required to form kinetic enolates is less.
3.7K
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
10.0K
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
10.0K