水溶液中の砂糖のシリケート複合体

Joseph B Lambert¹, Gang Lu, Stephanie R Singer

¹Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA. jlambert@northwestern.edu

Journal of the American Chemical Society

|August 5, 2004

まとめ

特定の砂糖は,シリシウム酸と溶解性シリケート複合体を形成しますが,特定のフーラノース形態のみが反応します. この無分子ヒドロキシル基を含む選択反応は,前生物化学に意味を持つ.

科学分野:

炭水化物化学炭水化物の化学
シリケート化学シリケート化学
プレビオティック化学プレビオティック化学

背景:

砂糖は,シリチウム酸と反応して,溶性シリケート複合体を形成することができます.
糖の構造と構成は,複合体の形成に極めて重要です.

研究の目的:

糖-酸複合体の形成のための構造的要件を調査する.
この反応の選択性とその潜在的な影響を理解する.

主な方法:

核磁共振 (NMR) スペクトロスコーピー,特に (29) Si と (13) C NMR を用いて,製品を分析した.
様々なモノサッカリドとディサッカリドの塩基性シリシ酸との反応を研究した.

主要な成果:

糖類のフーラノース形態のみが,シリチウム酸と反応し,2/1 (糖/シリチウム酸) チェラートを形成した.
反応には,アノメリックヒドロキシル基が隣接するヒドロキシル基にシスである必要があります.
リボース,キシロース,果糖などの特定の砂糖は複合体を形成するが,グルコースとギャラクトースはそうしなかった.

結論:

砂糖のシリケート複合体の形成は,砂糖の構造とヒドロキシル群の構成に依存して,非常に選択的です.
反応のメカニズムは,5つ構成のダイオラト環を介してケレーションを伴う.
この選択性は,プレバイオティクスの化学プロセスに役割を果たす可能性がある.

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