cis trans isomerism

简明释义

顺反异构

英英释义

例句

1.The cis trans isomerism 顺反异构现象 in fatty acids affects their melting points and biological functions.

脂肪酸中的cis trans isomerism顺反异构现象影响其熔点和生物功能。

2.In organic chemistry, understanding cis trans isomerism 顺反异构现象 is crucial for predicting the properties of compounds.

在有机化学中，理解cis trans isomerism顺反异构现象对预测化合物的性质至关重要。

3.Pharmaceuticals can exhibit cis trans isomerism 顺反异构现象, affecting their efficacy and safety.

药物可以表现出cis trans isomerism顺反异构现象，影响其有效性和安全性。

4.The difference between cis trans isomerism 顺反异构现象 can lead to drastically different chemical reactivities.

不同的cis trans isomerism顺反异构现象可能导致截然不同的化学反应性。

5.Chemists often use NMR spectroscopy to study cis trans isomerism 顺反异构现象 in alkenes.

化学家常用核磁共振光谱法研究烯烃中的cis trans isomerism顺反异构现象。

作文

Cis-trans isomerism, also known as geometric isomerism, is a fascinating concept in the field of chemistry that refers to the different spatial arrangements of atoms within a molecule. This phenomenon occurs due to the restricted rotation around double bonds or certain ring structures, leading to distinct isomers with different physical and chemical properties. The term 'cis' comes from the Latin word meaning 'on this side,' while 'trans' means 'across' or 'on the other side.' In the context of organic compounds, cis-trans isomerism is most commonly observed in alkenes, where the presence of a carbon-carbon double bond prevents free rotation.To illustrate this concept, consider 2-butene, which can exist in two isomeric forms: cis-2-butene and trans-2-butene. In cis-2-butene, the two methyl groups (–CH₃) are on the same side of the double bond, whereas in trans-2-butene, they are on opposite sides. This difference in arrangement leads to variations in their physical properties, such as boiling points and densities. For instance, cis-2-butene has a higher boiling point than trans-2-butene due to increased intermolecular forces resulting from its polar nature.The significance of cis trans isomerism extends beyond just physical properties; it also plays a crucial role in biological systems. Many biological molecules, including fats and amino acids, exhibit cis trans isomerism. For example, unsaturated fatty acids can have cis or trans configurations, which significantly influence their biological functions and health effects. Cis fatty acids tend to be more common in nature and are associated with beneficial health effects, while trans fatty acids, often found in processed foods, are linked to adverse health outcomes.In addition to its biological implications, cis trans isomerism is essential in the field of materials science. The properties of polymers can be altered by the configuration of their constituent monomers. For instance, the arrangement of repeating units in a polymer chain can dictate whether the material is flexible or rigid. Understanding cis trans isomerism allows chemists to design new materials with desired characteristics for specific applications, such as in the development of synthetic fibers or plastics.Moreover, cis trans isomerism has significant implications in pharmaceuticals. The efficacy and safety of drug compounds can be influenced by their geometric configuration. For instance, the drug thalidomide was marketed in both its cis and trans forms, but only one of those forms was effective as a sedative, while the other caused severe birth defects. This tragic case highlights the importance of understanding cis trans isomerism in drug development and the need for careful consideration of isomeric forms during the synthesis and testing of new pharmaceuticals.In conclusion, cis trans isomerism is a vital concept that permeates various fields of science, from organic chemistry to biology and materials science. Its implications are far-reaching, affecting everything from the physical properties of compounds to their biological functions and applications in medicine. As we continue to explore the complexities of molecular structures, the study of cis trans isomerism will remain a key area of focus, helping us unlock the secrets of the natural world and innovate for the future.

顺反异构现象，也称为几何异构现象，是化学领域中的一个迷人概念，指的是分子内原子的不同空间排列。由于双键或某些环结构周围的旋转受限，这种现象导致具有不同物理和化学性质的不同异构体。术语“顺”来自拉丁语，意为“在这一侧”，而“反”则意味着“在另一侧”。在有机化合物的上下文中，顺反异构现象最常见于烯烃，其中碳-碳双键的存在阻止了自由旋转。为了说明这一概念，考虑2-丁烯，它可以以两种异构体形式存在：顺-2-丁烯和反-2-丁烯。在顺-2-丁烯中，两个甲基（–CH₃）位于双键的同一侧，而在反-2-丁烯中，它们位于相对侧。这种排列上的差异导致它们的物理性质，如沸点和密度的变化。例如，顺-2-丁烯的沸点高于反-2-丁烯，这是由于其极性特性导致的分子间作用力增强。顺反异构现象的重要性不仅仅体现在物理性质上；它在生物系统中也起着至关重要的作用。许多生物分子，包括脂肪和氨基酸，都表现出顺反异构现象。例如，不饱和脂肪酸可以具有顺式或反式构型，这显著影响其生物功能和健康效应。顺式脂肪酸在自然界中更为常见，与有益的健康效应相关，而反式脂肪酸通常存在于加工食品中，与不良健康结果相关。除了生物学意义外，顺反异构现象在材料科学领域也至关重要。聚合物的性质可以通过其组成单体的构型进行改变。例如，聚合物链中重复单元的排列可以决定材料是柔韧还是刚性。理解顺反异构现象使化学家能够设计出具有特定应用所需特性的新的材料，比如在合成纤维或塑料的开发中。此外，顺反异构现象在制药领域也有重要影响。药物化合物的有效性和安全性可能受到其几何构型的影响。例如，药物沙利度胺以其顺式和反式形式上市，但只有一种形式作为镇静剂有效，而另一种形式则导致严重的出生缺陷。这一悲剧案例突显了在药物开发中理解顺反异构现象的重要性，以及在新药合成和测试过程中对异构体形式的仔细考虑的必要性。总之，顺反异构现象是一个重要的概念，渗透到科学的各个领域，从有机化学到生物学和材料科学。它的影响深远，涉及从化合物的物理性质到其生物功能和在医学中的应用。随着我们继续探索分子结构的复杂性，研究顺反异构现象将仍然是一个关键的关注领域，帮助我们揭示自然世界的秘密并为未来创新。