对于立体选择性1.1'-糖化酶的方法
Daniele Zucchetta1, Alla Zamyatina1
1Department of Natural Sciences and Sustainable Resources, Institute of Organic Chemistry, BOKU University, 1190 Vienna, Austria.
Beilstein journal of organic chemistry
|September 10, 2025
概括
通过1.1'-糖基化合成非还原分糖是开发新疗法和疫苗的关键. 实现对两个异构中心的立体选择性控制带来了重大的合成挑战.
科学领域:
- 碳水化合物化学 碳水化合物化学
- 葡萄糖生物学 葡萄糖生物学
- 有机合成 有机合成
背景情况:
- 非还原性分糖是各种生物分子的关键组成部分,包括菌根细菌的甘氨酸和病原体相关的分子模式 (PAMPs).
- 这些脱糖酸在宿主-病原体相互作用,细胞信号传递和疾病发展中起着至关重要的作用.
- 与自然资源的隔离往往会产生不纯或退化的产品,需要合成方法.
研究的目的:
- 审查最近在1.1 - - 糖化合成非还原性二糖化物合成的策略方面的进展.
- 突出1,1-链接分糖的立体选择性合成的挑战和重要性.
- 讨论疫苗研究,治疗和诊断中的应用.
主要方法:
- 选择的1.1 - - 糖化策略的概述.
- 讨论形成α,β-,β,β-,和α,α-1,1-糖化链的方法.
- 专注于立体选择性挑战,特别是与乳醇糖受体.
主要成果:
- 突出了最近在1,1-糖基化中取得的进展.
- 介绍了各种策略,以形成不同类型的1,1-链接分糖的不同立体同位素.
- 强调了在两个异构中心控制立体化学的固有困难.
结论:
- 强大的和立体选择性的合成策略对于生产复杂的含有1,1-二糖的生物分子至关重要.
- 克服1.1-糖基化中的挑战对于推进疫苗开发和治疗应用至关重要.
- 进一步研究立体选择性糖化,特别是具有挑战性的受体,是有必要的.
相关概念视频
01:24Oligosaccharide Assembly
3.5K
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...
3.5K
02:23SN2 Reaction: Stereochemistry
11.6K
In an SN2 reaction, the nucleophilic attack on the substrate and departure of the leaving group occurs simultaneously through a transition state. As the nucleophile approaches the substrate from the back-side, the configuration of the substrate carbon changes from tetrahedral to trigonal bipyramidal and then back to tetrahedral, leading to an inversion in the configuration of the product.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not...
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not...
11.6K
02:15SN1 Reaction: Stereochemistry
10.2K
This lesson provides an in-depth discussion of the stereochemical outcomes in an SN1 reaction.
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...
10.2K
01:25Protein Glycosylation
9.4K
Glycosylation, the most common post-translational modification for proteins, serves diverse functions. Adding sugars to proteins makes the proteins more resistant to proteolytic digestion. Glycosylated proteins can act as markers and receptors to promote cell-cell adhesion. Additionally, they have many essential quality control functions in the cell, such as correct protein folding and facilitating transport of misfolded proteins to the cytosol, which can be degraded.
Glycosylation occurs in...
Glycosylation occurs in...
9.4K
02:17Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
16.4K
If a set of reactants can yield multiple constitutional isomers, but one of the isomers is obtained as the major product, the reaction is said to be regioselective. In such reactions, bond formation or breaking is favored at one reaction site over others.
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
16.4K
02:36Regioselectivity and Stereochemistry of Hydroboration
9.4K
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
9.4K