チラリティの記憶のための三次アロマティックアミド:エナンチオ濃縮アルファ置換バリンへのアクセス
Mathieu Branca1, Didier Gori, Régis Guillot
1Laboratoire de Chimie des Procédés et Substances Naturelles, ICMMO, CNRS UMR 8182, Bât 410, Université Paris-Sud, F-91405 Orsay, France.
Journal of the American Chemical Society
|April 16, 2008
まとめ
新しい非対称合成法により,ダイナミックな軸性キラリティを使用して,キラル四次アルファアミノ酸を作成します. このヒラリティの記憶のアプローチは,高いエナチオ選択性を達成し,貴重なアミノ酸派生物を生み出します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・シンセシス
- チラルの化学
背景:
- 四次アルファアミノ酸は,医薬品の重要な構成要素である.
- 合成のための既存の方法は,しばしば効率性とエナチオセレクティブ性が欠けている.
研究 の 目的:
- 第四次アルファ置換アミノ酸の非対称合成のための新しい方法論を開発する.
- 効率的な立体化学制御のために,キラリティの概念の記憶を活用する.
主な方法:
- 三次アロマティックアミドのダイナミック・アクシャル・キラリティが採用されました.
- オクサゾリジン-5-オンの中間体は,L-バリンから合成されました.
- 中間物質のアルキル化により,様々な電ophiles が加えられ,その後,脱保護が行われます.
主要な成果:
- この方法論は,アルキル化ステップで良好な収穫量と高いエナチオ選択性 (96%まで) を達成しました.
- エナティオメリックに純粋な四分制産物は,再結晶化によって得られた.
- エナンチオ濃縮 (S) -アルファメチルバリン (ee=94%) とエナンチオピュア (S) -アルファ-イソプロピルアスパルティック酸 (ee>99%) を3つのステップで合成した.
結論:
- クォーターナーアルファアミノ酸の非対称合成のための堅牢な方法が確立されています.
- チラリティ戦略の記憶は,効率的なステレオ制御を提供します.
- このアプローチにより,貴重なキラルアミノ酸誘導体にアクセスできます.
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