Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
J Org Chem. 2009 Dec 18;74(24):9280-6. doi: 10.1021/jo901424v.
Phthalocyanines (Pcs) are excellent candidates for use as fluors for near-infrared (near-IR) fluorescent tagging of biomolecules for a wide variety of bioanalytical applications. Monofunctionalized Pcs, having two different types of peripheral substitutents, one for covalent conjugation of the Pc to biomolecules and others to improve the solubility of the macrocycle, are ideally suited for the desired applications. To date, difficulties faced during the purification of monofunctionalized Pcs limited their usage in various types of applications. Herein are reported a new synthetic method for rapid synthesis of the target Pcs and bioconjugation techniques for labeling of the oligonucleotides with the near-IR fluors. A novel synthetic route was developed utilizing a hydrophilic, poly(ethylene glycol) (PEG)-based support with an acid-labile Rink Amide linker. The Pcs were functionalized with an amine group for covalent conjugation purposes and were decorated with short PEG chains, serving as solubilizing groups. Microwave-assisted solid-phase synthetic method was successfully applied to obtain pure asymmetrically substituted monoamine functionalized Pcs in a short period of time. Three different bioconjugation techniques, reductive amination, amidation, and Huisgen cycloaddition, were employed for covalent conjugation of Pcs to oligonucleotides. The described microwave-assisted bioconjugation methods give an opportunity to synthesize and isolate the Pc-oligonucleotide conjugate in a few hours.
酞菁（Pcs）是将生物分子近红外（近红外）荧光标记为生物分析应用的荧光团的极好候选物。具有两种不同类型的外围取代基的单官能化 Pcs，一种用于将 Pc 共价连接到生物分子上，另一种用于提高大环的溶解度，非常适合所需的应用。迄今为止，在单官能化 Pcs 的纯化过程中遇到的困难限制了它们在各种类型的应用中的使用。本文报道了一种新的合成方法，用于快速合成目标 Pcs 以及用于用近红外荧光标记寡核苷酸的生物偶联技术。开发了一种新的合成途径，该途径利用具有酸不稳定的 Rink Amide 接头的亲水聚（乙二醇）（PEG）基支持物。将 Pcs 官能化，得到用于共价键合的胺基，并装饰有短 PEG 链，作为增溶基团。微波辅助固相合成方法成功地应用于在短时间内获得纯的不对称取代的单胺官能化 Pcs。使用了三种不同的生物偶联技术，即还原胺化、酰胺化和 Huisgen 环加成，用于将 Pcs 共价连接到寡核苷酸上。所描述的微波辅助生物偶联方法为在几个小时内合成和分离 Pc-寡核苷酸缀合物提供了机会。
