協調した核性アロマティック置換 (19F(-) と (18)F(-)
Constanze N Neumann1, Jacob M Hooker2,3, Tobias Ritter1,2,4
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|June 10, 2016
まとめ
新しい協調核性芳香置換反応 (CSNAr) は,従来のSNRの限界を回避し,電子が少ないアレンを必要とせずにPETイメージングのための新しい (18) Fラベル付き化合物の合成を可能にします.
科学分野:
- 有機化学
- 放射化学
- 化学生物学
背景:
- 核性アロマティック置換 (SNAr) は,アロマティック分子を機能化するための重要な方法であり,特にポジトロン放出トモグラフィ (PET) のイメージングのためにフッ素-18 ((18) F) を導入する.
- 伝統的なSNR反応は,負の電荷を持つマイゼンハイマー中間物質を安定させるために,電子欠乏の芳香基を必要とし,その範囲を制限する.
- 既存の (18) F ラジオラベル方式は,アゼオトロピク乾燥のような手ごわい手順を伴うことが多い.
研究 の 目的:
- 従来のSNRの基質の制限を克服する新しい協調核性芳香置換反応 (CSNAr) を導入する.
- フェノルの (18) F-デオキシフルオリネーションのための機能群耐性の方法を開発する.
- PETイメージングのための様々な (18) Fラベル付き化合物の合成を可能にします.
主な方法:
- フェノル脱酸化反応のメカニズムの調査.
- (18) Fの組み込みのためのCSNArプロトコルの開発と最適化.
- 新しいPET探査機の機能群耐性の実証と合成.
主要な成果:
- CSNAr反応が特定され,マイゼンハイマー中間体なしで進行し,電子が少ない領域を超えて範囲を拡大することが示された.
- 新しい (18) F-デオキシフルオリネーションが開発され,CSNArを段階的な異位化に優遇した.
- この方法により,フェノールからアゼオトロプ的乾燥なしに選択的に (18) Fを導入し,以前は入手不可能な放射性マーケルの化合物を得ることができる.
結論:
- CSNAR反応は,芳香的機能化のための伝統的なSNRに多用途の代替手段を提供します.
- この新しいアプローチは,容易に入手可能なフェノールから (18) Fでラベルを貼ったPETプローブの合成を簡素化します.
- 開発された方法は,PETイメージングアプリケーションのための新しい放射線追跡器へのアクセスを拡大します.
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