Abstract

Bis-alkylsulfonic acid and polyethylene glycol (PEG)-substituted BF₂ azadipyrromethenes have been synthesized by an adaptable and versatile route. Only four synthetic stages were required to produce the penultimate fluorophore compounds, containing either two alcohol or two terminal alkyne substituents. The final synthetic step introduced either sulfonic acid or polyethylene glycol groups to impart aqueous solubility. Sulfonic acid groups were introduced by reaction of the bis-alcohol-substituted fluorophore with sulfur trioxide, and a double Cu(I)-catalyzed cycloaddition reaction between the bis-alkyne fluorophore and methoxypolyethylene glycol azide yielded a neutral bis-pegylated derivative. Both fluorophores exhibited excellent near-infrared (NIR) photophysical properties in methanol and aqueous solutions. Live cell microscopy imaging revealed efficient uptake and intracellular labelling of cells for both fluorophores. Their simple synthesis, with potential for last-step structural modifications, makes the present NIR-active azadipyrromethene derivatives potentially useful as NIR fluorescence imaging probes for live cells.

中文翻译：

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水溶性1,9-二烷基取代的BF 2氮杂二吡咯亚甲基荧光团的合成与性能

摘要

双烷基磺酸和聚乙二醇（PEG）取代的BF ₂氮杂吡咯烷酮已通过一种适应性强的通用途径合成。只需四个合成步骤即可生产出倒数第二个荧光团化合物，该化合物含有两个醇或两个末端炔烃取代基。最终的合成步骤引入了磺酸或聚乙二醇基团以赋予水溶性。通过双醇取代的荧光团与三氧化硫的反应引入磺酸基团，并且双炔基荧光团与甲氧基聚乙二醇叠氮化物之间的双Cu（I）催化的环加成反应生成了中性的双聚乙二醇化衍生物。两种荧光团在甲醇和水溶液中均表现出出色的近红外（NIR）光物理性质。活细胞显微镜成像显示两种荧光团对细胞的有效吸收和细胞内标记。它们的简单合成，具有最后一步结构修饰的潜力，使本发明的NIR活性氮杂二吡咯亚甲基衍生物可用作活细胞的NIR荧光成像探针。