一个基纯净的基结合组件
L J Prins1, F De Jong, P Timmerman
1Laboratory of Supramolecular Chemistry and Technology, MESA Research Institute, University of Twente, Enschede, The Netherlands.
Nature
|November 23, 2000
概括
研究人员使用键创建了稳定的性超分子组合. 这一突破使得能够分离出酶体纯结构,克服弱相互作用和种族化所面临的挑战.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 奇拉性研究 奇拉性研究
背景情况:
- 性分子存在于非叠加的镜像中,称为反体.
- 通过合成或分离的racemic混合物,可以获得纯净的enantiomeric化合物.
- 状超分子组合,特别是那些来自像键这样的弱相互作用的组合,容易发生种族化,使得它们的隔离变得困难.
研究的目的:
- 设计和合成稳定的性超分子组件,使用性构建块.
- 为了克服在键组件中的种族化挑战.
- 展示一种"合性记忆"策略,用于诱导和分离超分子合性.
主要方法:
- 使用的阿希拉尔[4]arene二甲胺和酸盐.
- 采用多个合作的键来稳定组件.
- 应用了一种"合性记忆"方法,使用合性巴比酸盐,然后用合物替代.
- 在中研究了组合稳定性和种族化动力学.
主要成果:
- 成功地设计和形成稳定的状超分子组件从状元件.
- 实现了对抗分子纯超分子结构的隔离.
- 证明了合作的键增强了组件的稳定性,防止种族化.
- 在中在室温下观察到超过四天的racemization半衰期.
结论:
- 开发了一种创新的策略,用于创建稳定,分子结合的超分子组件.
- "合性记忆"概念有效地转移和稳定了超分子系统中的合性.
- 这项工作提供了一种可行的方法来解决和分离通过弱相互作用形成的奇拉组合.
相关概念视频
01:32Chemiosmosis
Oxidative phosphorylation is a highly efficient process that generates large amounts of adenosine triphosphate (ATP), the basic unit of energy that drives many cellular processes. Oxidative phosphorylation involves two processes— the electron transport chain and chemiosmosis.
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons reduce...
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons reduce...
02:31Elements: Chemical Symbols and Isotopes
A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is used to indicate one atom of mercury (microscopic domain) or to label a container of many atoms of the element mercury (macroscopic domain).
Some symbols are derived from the common English name of the element; others are abbreviations of the name in another language — Latin, Greek or German. For example, the symbol for aluminum (common name)...
Some symbols are derived from the common English name of the element; others are abbreviations of the name in another language — Latin, Greek or German. For example, the symbol for aluminum (common name)...
01:27The Periodic Table and Organismal Elements
Elements are the smallest units of matter that cannot be broken down further by chemical processes. There are 118 known elements, but not all of these are naturally occurring, and only a few of them are essential for life. Living matter is composed primarily of carbon, nitrogen, hydrogen, and oxygen, with smaller amounts of other elements like calcium, phosphorus, potassium, and sulfur. Other elements are also necessary for life but only in trace amounts.
Periodic Table Provides Information...
Periodic Table Provides Information...
01:22EDTA: Chemistry and Properties
Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...
01:09EDTA: Conditional Formation Constant
Each EDTA molecule has six binding sites: four carboxyl groups and two amino groups. The fully protonated form of EDTA is represented as H6Y2+. However, it can exist in different forms, H5Y+, H4Y, H3Y−, H2Y2−, and HY3−, depending on the pH of the solution. In very basic solutions with pH > 10.17, the fully deprotonated form, Y4−, is the predominant species that readily complexes with metal ions in a 1:1 ratio.
For the equilibrium reaction of the metal with the Y4− form of EDTA, the formation...
For the equilibrium reaction of the metal with the Y4− form of EDTA, the formation...
01:26EDTA: Auxiliary Complexing Reagents
EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...