ニコチンの2つの環への水素結合の間の干渉
Jérôme Graton1, Tanja van Mourik, Sarah L Price
1Centre for Theoretical and Computational Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom.
Journal of the American Chemical Society
|May 8, 2003
まとめ
ニコチンはニコチンです.
科学分野:
- バイオケミストリー バイオケミストリー
- コンピューティング・ケミストリー
- 分子モデリング
背景:
- ニコチンの生化学的輸送と結合は,水素結合に依存しています.
- 2つの異なる水素結合部位が存在する:ピリジン環と陽子化されたピロリジニウム環.
- ニコチンの相互作用におけるこれらの部位の独立性は完全に理解されていません.
研究 の 目的:
- 陽子化されたニコチンにおける水素結合部位の独立性を調査する.
- ニコチンと水,バイカーボネート,ベンゼン,インドールとの相互作用をモデル化するために.
- これらの相互作用がニコチンの構造と結合に与える影響を評価する.
主な方法:
- 様々な分子 (水,二酸化炭素,ベンゼン,インドール) を含むニコチンクラスターの計算された構造.
- 分子間アニソトロピック原子-原子モデルの潜在力を用いて潜在エネルギー表面を調査した.
- 密度関数理論 (DFT) を用いて完全な幾何学最適化を行い,非添加的効果を含めた.
主要な成果:
- ニコチンのピロリジン窒素のプロトネーションはピリジン環の水素結合に影響します.
- ビカルボネートアニオンはピリジン環の水素結合能力を部分的に回復させる.
- ベンゼンとインドールは異なる相互作用を行い,インドールはピリジン窒素の能力を部分的に回復します.
- 2番目の水分子は,ニコチンの重要な形状変化を誘導する.
結論:
- ニコチンの水素結合部位の独立性は限られており,従来の予測に挑戦しています.
- アニオンや芳香分子との相互作用は,水素結合能力を調節する.
- 結果は,生化学システムにおける原子モデル化のためのベンチマークを提供します.
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