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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
チラリティの記憶による非対称サイクリング:四次元のステレオセンターを持つサイクルアミノ酸への簡潔なアクセス
Takeo Kawabata1, Shimpei Kawakami, Swapan Majumdar
1Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan. kawabata@scl.kyoto-u.ac.jp
Journal of the American Chemical Society
|October 23, 2003
まとめ
研究者らは,天然のアミノ酸から四次元のステレオセンターを持つサイクルアミノ酸を合成するための新しい方法を開発しました. このプロセスはキラリティを保ち,アゼチジジンやピロリジンなどの高度にエナチオメリックに富んだアザサイクリック化合物を生成します.
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
- 薬用化学 薬用化学について
背景:
- チラルのサイクルアミノ酸は,医薬品や天然製品の重要な構成要素です.
- 合成のための効率的でステレオ選択的な方法の開発は,有機化学における重要な課題です.
研究 の 目的:
- 四次性ステレオセンターを持つサイクルアミノ酸の非対称合成のための新しい方法を開発する.
- サイクライゼーション反応のステレオ化学的結果と範囲を調査する.
主な方法:
- 天然アルファアミノ酸から N-Omega-Bromoalkyl) -アミノ酸誘導体の調製.
- これらの誘導体の処理は,N,N-ジメチルホルマミド (DMF) のカリウムヘクサメチルジジラジル化物 (KHMDS) で行う.
- 生成された循環性アミノ酸の産量,純度,およびエナティオメール過量 (ee) の分析.
主要な成果:
- アゼテディジン,ピロリジン,ピペリジン,アゼパン誘導体を含むサイクルアミノ酸の合成に成功しました.
- 基因アミノ酸のキラリティの高い保存,最大98%e.e.で得られる製品.
- サイクル構造の範囲にメソッドの適用性の実証.
結論:
- 開発された方法は,四次性ステレオセンターを持つエナティオメリックに濃縮された循環性アミノ酸への効率的な経路を提供します.
- ステレオ化学は,主として,起点の天然のアミノ酸から保持されます.
- サイクライゼーションは,おそらく軸性キラルエノラート中間体を通過し,非対称な合成メカニズムについての洞察を提供します.
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