ピリジル硫キシミンの触媒的エナチオセレクティブ合成
1Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States.
Journal of the American Chemical Society
|June 14, 2021
まとめ
チラル硫キシミンは,非対称なN酸化のためのペプチド触媒を用いて合成された. この方法は高いエナチオセレクティビティを提供し,導向群を簡単に除去し,貴重なN-Hスルフォキシミンを生成します.
科学分野:
- 有機化学
- 非対称な触媒
- 薬剤化学
背景:
- サルフォキシミンは独特の化学的および生物学的性質を有し,研究に大きな関心を持っています.
- サルフォキシミンの非対称合成は,利用可能な触媒方法が限られているため,依然として課題です.
- 薬剤開発と材料科学における重要な構成要素である.
研究 の 目的:
- キラルスルフォキシミン合成のための新しい非対称な触媒方法を開発する.
- ピリジルスルフォキシミンの非対称化N酸化のためのペプチド触媒の使用を調査する.
- サブストラット改変と触媒構造がエナンチオセレクティビティに及ぼす影響を調査する.
主な方法:
- アスパルティック酸を含むペプチド触媒を用いて,ピリジル硫キシミンのN酸化を非対称化する.
- エナチオインダクションを強化するために,基板の指示グループを使用します.
- 異なるC末端保護群 (メチルエステル対メチルアミド) を有するペプチドを用いて,エナンチオメールの形成を制御する.
主要な成果:
- 高いエナチオメール比率 (最大99: 1 er) を有するキラル硫黄素酸化物の合成に成功した.
- 指示グループがエナチオインダクションを大幅に改善し,容易に除去できることを示す.
- ペプチド触媒のC末端保護群を基に対極エナチオマー形成の観察
結論:
- 新しく効率的なペプチド触媒によるキラルスルフォキシミン合成が確立された.
- 開発された方法は,エナチオメリックに濃縮されたN-Hスルフォキシミンへの多用途な経路を提供します.
- 提案された結合モデルは,観察されたエナチオ選択性を説明し,立体化学的結果の制御における触媒の役割を強調する.
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