消失し,再出現するポリモルフ. ベンゾカイン:ピクリック酸システム
J O Henck1, J Bernstein, A Ellern
1Institut für Pharmakognosie der Universität Innsbruck Innrain 52, Josef-Moeller-Haus, 6020 Innsbruck, Austria.
Journal of the American Chemical Society
|July 18, 2001
まとめ
ベンゾカイン (BC) とピクリック酸 (PA) システムを調査した結果,難解な多形形の結晶化方法が明らかになった. 熱的振る舞いを理解することは,メタステーブルな結晶構造を得るための鍵です.
科学分野:
- クリスタログラフィーです.
- マテリアルサイエンス 材料科学
- 化学工学は化学工学というものです.
背景:
- ベンゾカイン:ピクリック酸 (BC:PA) 1: 1複合体は,以前,a を表していました.
- 消えるポリモルフ
- 隔離が難しいメタステーブルな形態である.
- 製薬コクリスタルのポリモルフィズムは,薬剤の安定性および生物利用性にとって重要である.
研究 の 目的:
- ベンゾカイン:ピクリック酸 (BC:PA) システムを再調査する.
- さまざまなBC:PAフェーズに対して,堅牢な結晶化手順を開発する.
- メタステーブルな多形形態の結晶化の条件を理解する.
主な方法:
- 熱分析のための熱顕微鏡と微分スキャニング熱計 (DSC).
- 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー.
- 構造的決定のためのX線結晶学.
- 水素結合の特徴化のためのグラフセット分析.
主要な成果:
- BC:PAシステムの相図が作成されました.
- 4つの異なる結晶相が特定され,特徴づけられた: 2つの1:1複合体,1:1水素,および2:1複合体.
- 構造分析により,各相における特定の水素結合パターンが明らかになった.
- 熱的行動に基づいて,転移安定形態の結晶化のための戦略が開発されました.
結論:
- 熱測定法と組み合わせた徹底した熱分析により,入手が難しい,転移安定した多形形の結晶化が可能になります.
- 段階的振る舞いを理解することは,共結晶システムの結晶化を制御するために不可欠です.
- この研究は,他の化学系におけるメタステーブルポリモルフへのアクセスのための枠組みを提供します.
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