アミノ酸の結晶工学による溶液相ホモキラリティの出現
Martin Klussmann1, Toshiko Izumi, Andrew J P White
1Department of Chemistry, Imperial College London, London SW7 2AZ, U.K.
Journal of the American Chemical Society
|May 29, 2007
まとめ
科学者たちは,高度にエナチオイン濃縮されたアミノ酸溶液を作成する方法を探索しました. アキラル二カルボキシル酸を加えることで,98%以上のエナティオメリック過剰を達成し,同キラリティの進化のための新しいメカニズムを提供した.
科学分野:
- プレビオティック化学 プレビオティック化学
- クリスタル・エンジニアリング (Crystal Engineering) とは
- チラルの化学
背景:
- 生物系におけるホモキラリティ (一つのエナチオメルの優位性) が,レースミックなプレバイオティクスの環境から生じたのは,依然として重要な科学的問題である.
- この過程を理解することは,生命の化学の初期段階を解読する上で極めて重要です.
研究 の 目的:
- 高度にエナチオ濃縮されたアミノ酸溶液を生産するための新しい方法を調査する.
- ホモキラリティの達成におけるアミノ酸相行動と共結晶化の役割を調査する.
- プレバイオティクスの化学とエナティオメアの分離に関連するメカニズムを提案する.
主な方法:
- 水性LおよびDアミノ酸混合物の相行動の操作.
- アキラル二カルボキシル酸を加えて,キラルアミノ酸とコクリスタルを形成する.
- エウテクティック組成物の分析により,エナティオメリック過剰 (ee) を決定する.
主要な成果:
- アキラル二酸化炭素酸が,アミノ酸混合物のユーテクティック成分を調節できることを実証した.
- 高濃度エンアンチオンの溶液が得られ,いくつかのシステムでは98%EE以上の化合物が得られました.
- ホモキラリティの進化のための一般的で簡単なメカニズムを特定した.
結論:
- この研究は,制御された共結晶化によるホモキラリティの prebiotic 進化のための実行可能なメカニズムを提示します.
- このアプローチは,ラセミック化合物のエナティオメールを分離するための概念的進歩を提供します.
- この発見は,初期の地球化学の文脈で,現代の結晶工学原理の先駆者を示唆しています.
関連する概念動画
Chirality in Nature
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid. The...
Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
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.
Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chirality at Nitrogen, Phosphorus, and Sulfur
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
Molecules with Multiple Chiral Centers
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...


