Department of Chemistry and RECETOX , Masaryk University , Kamenice 5, 625 00 Brno , Czech Republic.
J Am Chem Soc. 2019 May 1;141(17):7155-7162. doi: 10.1021/jacs.9b02537. Epub 2019 Apr 23.
Cyanine dyes play an indispensable and central role in modern fluorescence-based biological techniques. Despite their importance and widespread use, the current synthesis methods of heptamethine chain modification are restricted to coupling reactions and nucleophilic substitution at the meso position in the chain. Herein, we report the direct transformation of Zincke salts to cyanine dyes under mild conditions, accompanied by the incorporation of a substituted pyridine residue into the heptamethine scaffold. This work represents the first general approach that allows the introduction of diverse substituents and different substitution patterns at the C3'-C5' positions of the chain. High yields, functional tolerance, versatility toward the condensation partners, and scalability make this method a powerful tool for accessing a new generation of cyanine derivatives.
菁染料在现代基于荧光的生物技术中起着不可或缺的核心作用。尽管它们非常重要且用途广泛，但目前对七甲川链修饰的合成方法仅限于在链中的中位进行偶联反应和亲核取代反应。在此，我们报告了在温和条件下将 Zincke 盐直接转化为菁染料，同时将取代的吡啶残基引入到七甲川支架中。这项工作代表了第一个通用方法，允许在链的 C3'-C5'位置引入不同的取代基和不同的取代模式。高产率、功能耐受性、对缩合伙伴的通用性以及可扩展性使这种方法成为获得新一代菁染料衍生物的有力工具。
