水中のピリドクサールにグライシンを加えたクライゼン式
Krisztina Toth1, Tina L Amyes, John P Richard
1Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, USA.
Journal of the American Chemical Society
|August 26, 2004
まとめ
ピリドクサルの化学反応は予期せぬ形で,トランスアミネーションやデウテリウム交換ではなく,クライスン型添加製品をもたらした. これは,水中の5'-デオキシピリドクサルの安定化されたグリシンエノラートの選択的反応性を強調しています.
科学分野:
- バイオケミストリー バイオケミストリー
- 有機化学 オーガニック・ケミストリー
- 酵素触媒は,酵素触媒として作用する.
背景:
- ピリドクサルは,生物学的トランスアミネーション反応における重要なコファクターである.
- グリシンは最も単純なアミノ酸であり,しばしば酵素処理に関与します.
- デウテリウム交換は,反応機構と陽子の移動性を探査することができます.
研究 の 目的:
- 5acute{}-デオキシピリドクサールとグリシンの反応産物を脱塩水で調査する.
- ピリドクサール触媒によるトランスアミネーションまたはデウテリウム交換が起きているかどうかを判断する.
- 観察された予期せぬ反応性を理解するために.
主な方法:
- D2Oにおけるグリシンと5acute-デオキシピリドクサルの反応.
- pD コントロールは7.0で7.0です.
- 反応製品の分析.
主要な成果:
- 重要なトランスアミネーションやデウテリウム交換は観察されなかった.
- クレイゼン型加法による2つのダイアステロエーマー産物の定量産数.
- グリシンエノラートは,5つの急性-デオキシピリドクサルのカルボニル群に選択的に加わります.
結論:
- この反応は,予想されるピリドクサルの化学反応よりも,クレイセン型添加を好む.
- 5急性デオキシピリドクサルで安定したグリシンエノラートは,水へのカルボニル添加に対する高い選択性を示す.
- この発見は,ピリドクサルの誘導体の反応性に関する新しい洞察を提供します.
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