分子内H結合の限界
Thomas A Hubbard, Alisdair J Brown1, Ian A W Bell1
1Afton Chemical Limited , London Road, Bracknell, Berkshire RG12 2UW, U.K.
Journal of the American Chemical Society
|December 10, 2016
まとめ
分子内の水素結合は,距離に依存する値で,より強くなります. これは分子認識に影響を及ぼし,内部結合はしばしば外部結合に勝る.
科学分野:
- 物理化学
- 分子生物物理学
- 超分子化学
背景:
- 水素結合は分子認識のプロセスに不可欠です.
- 水素結合形成のエネルギー予測は,競合する前組織化および柔軟性要因のために困難である.
研究 の 目的:
- リンカーの長さに基づいて分子内水素結合の強さを定量化する.
- 水素結合エネルギーに対する分子柔軟性の影響を理解する.
- 分子構造の回転性結合に伴うエネルギーペナルティを決定する.
主な方法:
- 分子内相互作用エネルギーの実験的測定
- 水素結合ドナー部位と受容部位を分離する結合体の系統的な変化.
- 距離による水素結合の強さの分析
主要な成果:
- 距離に依存する値が分子内水素結合の強さで観察された.
- 6回転結合によって分離されたとき,水素結合は著しく弱かった (<−1 kJ mol−1).
- より強い内部水素結合 (−5〜−9 kJ mol−1) は ≤5 のローターで観察され,外部受容体を上回った.
- ローターあたり5〜6kJのmol−1の一貫したエネルギーペナルティが,4回転可能な結合を持つ分子で発見された.
結論:
- 回転可能な結合の数によって定量化される分子柔軟性は,分子内水素結合の強さに重大な影響を及ぼします.
- 観測された距離依存の値は,強い水素結合のための構成先の組織化の重要性を強調する.
- これらのエネルギー貢献を理解することは 特定の認識特性を有する分子を設計するのに不可欠です
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