1-氨基cyclopropanecarboxylic 酸 (Ac3c) 的独特气相结构
Ana I Jiménez1, Vanesa Vaquero, Carlos Cabezas
1Departamento de Química Orgánica, ISQCH, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain.
Journal of the American Chemical Society
|June 3, 2011
概括
研究人员确定了1-aminocyclopropanecarboxylic acid (Ac(3) c) 的三个独特的气相结构. 一个以前未被观察到的"缺失符合性",通过键稳定,首次在具有非极性侧链的氨基酸中被检测到.
科学领域:
- * 分子光谱学
- * * 量子化学 是一个量子化学.
- * * 结构生物学 结构生物学
背景情况:
- * 非蛋白质氨基酸在生物系统中起着至关重要的作用.
- *对氨基酸在气相中的形态分析对于理解它们的内在性质至关重要.
- *1 - 氨基cyclopropanecarboxylic 酸 (Ac(3) c) 中的循环环表明了独特的结构特征.
研究的目的:
- * 为了研究1-aminocyclopropanecarboxylic acid (Ac(3) c) 的气相结构.
- * 为了识别和描述Ac(3) c型态的键模式.
- * 探索环环对氨基酸构成的影响.
主要方法:
- * 激光除以蒸发Ac(3) c. 的作用.
- *分子束里叶变换微波光谱学用于气相分析.
- * Ab initio计算用于预测和比较旋转和核四极合常量.
主要成果:
- *三种不同的Ac(3) c的符合者被明确地确定.
- * 两个对应物类似于编码的阿里法特氨基酸中发现的.
- * 一部小说
- 缺少的一种调整器.
- 稳定由N-H····· H) 键,在具有非极性侧链的气态氨基酸中首次被检测出来.
结论:
- * Ac(3) c的独特形状景观受到环环与碳基之间的结合相互作用的影响.
- * 检测到的时间
- 缺少的一种调整器.
- 提供了对氨基酸的构造可能性的新见解.
- * 这项研究扩大了对气相中氨基酸结构的理解.
相关概念视频
01:28Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
01:16IUPAC Nomenclature of Carboxylic Acids
IUPAC names of carboxylic acids are systematically derived following a few rules discussed below.
For acyclic saturated monocarboxylic acids, the longest hydrocarbon chain containing the –COOH carbon is identified as the parent chain. Then, the last -e of the parent hydrocarbon name is replaced with a suffix -oic acid.
For acyclic saturated monocarboxylic acids, the longest hydrocarbon chain containing the –COOH carbon is identified as the parent chain. Then, the last -e of the parent hydrocarbon name is replaced with a suffix -oic acid.
01:16Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
Naming Acid Halides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
01:11Nomenclature of Carboxylic Acid Derivatives: Amides and Nitriles
Naming Amides
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
01:15Carboxylic Acid Derivatives: Overview
Carboxylic acid derivatives are formed by replacing the hydroxyl group of carboxylic acids with a different functional group. The most common carboxylic acid derivatives are:
01:07Preparation of Acid Anhydrides
One of the methods for preparing symmetrical or unsymmetrical acid anhydrides involves the treatment of acid chlorides with the sodium salt of carboxylic acids. The reaction proceeds via a nucleophilic acyl substitution.
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...