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キュルビット[n]ウリル (n = 7, 8) とカチオン型ダイヤモンド体との構造-親和関係を解明する
David Sigwalt1, Marina Šekutor2, Liping Cao1
1Department of Chemistry and Biochemistry, University of Maryland , College Park, Maryland 20742, United States.
Journal of the American Chemical Society
|February 10, 2017
まとめ
キュルビト[n]ウリル (CB[7]とCB[8]) は,アダマンタンとダイアマンタンと強い結合を示している. CB[8]はフェムトモラー結合親和性を示し,CB[n]ファミリーの最も緊密な結合宿主として発展する可能性を示唆する.
科学分野:
- 超分子化学
- ホスト・ゲスト・ケミストリー
- NMRスペクトロシー
背景:
- キュルビット[n]ウリル (CB[n]) は,独特の腔構造を持つマクロサイクル宿主である.
- 新しい超分子システムを設計するには ゲスト結合の相性を理解することが重要です
研究 の 目的:
- キュキュルビット[7]ウリル (CB[7]) とキュキュルビット[8]ウリル (CB[8]) の結合定数 (Ka) を様々なアダマンタンおよびダイアマンタン誘導体で測定する.
- 誘導体構造,イオン二極相互作用,ポータル幾何学など,結合親和に影響を与える要因を調査する.
- CB[n]ホスト-ゲスト複合体の安定性を高めるための戦略を探求する.
主な方法:
- 結合定数を決定するための直接的および競争的1H NMRスペクトロスコーピー
- ゲスト結合の構造的基礎を分析するX線結晶学.
- ギブス結合の自由エネルギーを推定する非経験的量子力学計算.
主要な成果:
- CB [7] と CB [8] は,アダマンタンとダイアマンタンへの重要な結合親和性を示しています.
- CB[8]·IsoDiam(NHMe2)2複合体は,CB[7]·Diam(NMe3)2に匹敵するフェムトモラ結合親和性を示している.
- ゲストの幾何学とポータルの相互作用は,特定のループ戦略によるより大きな親和感の強化を示すCB[8]で,結合に著しく影響する.
- アルキル群の化により,期待通り結合親和性が増加しなかった.
- 構造分析により,特定の幾何学的な制約と,結合モードに影響を与える密接な接触が明らかになった.
結論:
- CB[8]は例外的な結合能力を示し,CB[n]ファミリーの中で最も強い結合を持つホストの有望な候補として位置づけられています.
- この研究は,構造的および電子的要因を理解することによって,ホスト-ゲストの相互作用を最適化するための洞察を提供します.
- CB[8]ベースのシステムのさらなる開発は,分子認識とカプセル化における高度なアプリケーションにつながる可能性があります.
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