ペプトイドポリマーの分子構造と結晶構造の普遍的関係と cis 脊椎形状の流行
Douglas R Greer1,2, Michael A Stolberg1, Joyjit Kundu3
1Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|January 9, 2018
まとめ
ペプトイドポリマーは結晶に共通する構造的モチーフを示し,全シス骨格の延長された平らな形状を採用する. この発見は,X線散射とシミュレーションによって明らかにされ,孤立した分子行動と対照的です.
科学分野:
- ポリマー科学
- 材料科学
- クリスタルグラフィー
背景:
- ペプトイドポリマーは固体状態での結晶性で知られている.
- これまでの研究は,結晶型ペプトイドポリマーに共通する構造モチーフを特定できなかった.
研究 の 目的:
- ペプトイドポリマーの分子構造と結晶構造の関係を調査する.
- さまざまなペプトイド共ポリマーと以前に報告されたポリマーに共通する構造的特徴を特定する.
主な方法:
- サイドチェーン (S) とメインチェーン (N) の長さが異なるペプトイド共ポリマーの合成とX線散乱分析.
- 18個のペプトイドポリマーから得られた既存のX線散射データを分析した.
- ペプトイドポリマーの分子動態シミュレーション
主要な成果:
- S と N の関数として,単位のセル寸法 (a,b,c) の単純な予測関係を確立した.
- これらの関係が大量結晶と自己組み立てナノシートの両方に当てはまることが示されました.
- ペプトイドポリマーは固体状態と自己組み立て構造で拡張された平面形状を採用することを明らかにした.
- 分子ダイナミクスのシミュレーションは,パックされた構造におけるバックボーンアミドのオール-シス形状を好むことを示した.
結論:
- ペプトイドポリマーは,サイドチェーンとメインチェーンの長さに基づいて予測可能な単位細胞寸法を持っています.
- 分子は,状態 (大量結晶または自己組み立てナノシート) にかかわらず,拡張された平面形状を採用します.
- 結晶および超分子構造では,ペプトイドポリマーは,単離された分子の好みとは対照的に,オール-シス骨格形状を好みます.
関連する概念動画
Ionic Crystal Structures
18.1K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
18.1K
Structure of Lipids
99.5K
Lipids include a diverse group of compounds that are largely nonpolar in nature. This is because they are hydrocarbons that include mostly nonpolar carbon-carbon or carbon-hydrogen bonds. Non-polar molecules are hydrophobic (“water fearing”), or insoluble in water. Lipids perform many different functions in a cell. Cells store energy for long-term use in the form of fats. Lipids also provide insulation from the environment for plants and animals. For example, they help keep aquatic...
99.5K
Molecular Structure and Acidity
21.7K
An acid can be deprotonated to form a conjugate base or an anion. If the produced anion is more stable, then the acid is stronger. On the contrary, if the anion is unstable, then the acid is weaker. Hence, to determine the acidity of the compound, the stability of its conjugate base is studied using various factors.
The size effect explains the change in atomic size on acidity. When comparing the acids formed from elements that belong to the same column in the periodic table, their atomic sizes...
The size effect explains the change in atomic size on acidity. When comparing the acids formed from elements that belong to the same column in the periodic table, their atomic sizes...
21.7K
Structure-Activity Relationships and Drug Design
1.8K
Drug design is a dynamic field that involves discovering and developing new medications based on specific biological targets. This process heavily relies on structure-activity relationships (SAR) and quantitative structure-activity relationships (QSAR) to guide the design and optimization of efficient drugs.
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence...
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence...
1.8K
Acid Strength and Molecular Structure
33.2K
Binary Acids and Bases
In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
33.2K
Lewis Structures of Molecular Compounds and Polyatomic Ions
46.5K
To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:
46.5K


