Abstract

A practical synthesis for 6,8-difluoro-7-hydroxycoumarin-3-carboxylic acid – one of the most widely used coumarin fluorescence imaging dye for bioconjugation – is reported. The synthesis was optimized for a preparative scale to obtain 14 g of the fluorescent coumaryl acid, 6,8-difluoro-7-hydroxycoumarin-3-carboxylic acid. Using this sequence, the preparation of its NHS ester requires a single chromatographic separation for a total of eight synthetic steps. Coupling of the key coumaryl NHS ester is also demonstrated with an unprotected hydroxyamine linker chain for further derivatization. This report provides a convenient access to the fluorinated dye for research labs as an alternative to currently cost-prohibitive commercial sources.

A practical synthesis for 6,8-difluoro-7-hydroxycoumarin-3-carboxylic acid – one of the most widely used coumarin fluorescence imaging dye for bioconjugation – is reported. The synthesis was optimized for a preparative scale to obtain 14 g of the fluorescent coumaryl acid, 6,8-difluoro-7-hydroxycoumarin-3-carboxylic acid. Using this sequence, the preparation of its NHS ester requires a single chromatographic separation for a total of eight synthetic steps. Coupling of the key coumaryl NHS ester is also demonstrated with an unprotected hydroxyamine linker chain for further derivatization. This report provides a convenient access to the fluorinated dye for research labs as an alternative to currently cost-prohibitive commercial sources.

中文翻译：

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实用的6,8-二氟-7-羟基香豆素衍生物的荧光合成

摘要

据报道，一种实用的合成方法是6,8-二氟-7-羟基香豆素-3-羧酸（一种最广泛用于生物缀合的香豆素荧光成像染料）。将该合成进行了制备规模的优化，以获得14g的荧光香豆酸，6，8-二氟-7-羟基香豆素-3-羧酸。使用此序列，其NHS酯的制备需要进行一次色谱分离，总共需要八个合成步骤。还证明了关键的香豆基NHS酯与未保护的羟胺接头链的偶联可进一步衍生化。该报告为研究实验室提供了一种方便的获取氟化染料的方法，可以替代目前成本过高的商业来源。

据报道，一种实用的合成方法是6,8-二氟-7-羟基香豆素-3-羧酸（一种最广泛用于生物缀合的香豆素荧光成像染料）。将该合成进行了制备规模的优化，以获得14g的荧光香豆酸，6，8-二氟-7-羟基香豆素-3-羧酸。使用此序列，其NHS酯的制备需要进行一次色谱分离，总共需要八个合成步骤。还证明了关键的香豆基NHS酯与未保护的羟胺接头链的偶联可进一步衍生化。该报告为研究实验室提供了一种方便的获取氟化染料的方法，可以替代目前成本过高的商业来源。