Through thiol‐ene photopolymerization of presynthesized oligomers, advanced clickable nucleic acids (CNA‐2G) are synthesized with sequence‐controlled repeating units. As examples, poly(thymine‐adenine) (polyTA) CNA‐2G and poly(thymine‐thymine‐cytosine) CNA‐2G are synthesized by polymerizing thiol‐ene heterofunctional dimers with pendant thymine‐adenine nucleobases and trimer with pendant thymine‐thymine‐cytosine nucleobases. Based on size exclusion chromatography (SEC) analysis, polyTA and polyTTC have number average molecular weights of 2000 and 1800, respectively, which contain 7–8 pendant nucleobases. Based on the different behavior of the CNA‐2G monomers and CNA‐2G oligomers with two or more pendant nucleobases in photopolymerization, an unusual thiol‐ene chain‐growth propagation mechanism is observed for the former and a common thiol‐ene step‐growth propagation mechanism for the latter. The uncommon thiol‐ene chain‐growth propagation is hypothesized to rely on a six‐membered ring mediated intramolecular hydrogen atom transfer process.

中文翻译：

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高级可点击合成寡核苷酸的序列控制合成。

通过预合成的低聚物的硫醇烯光聚合，可以合成具有序列控制重复单元的高级可点击核酸（CNA-2G）。例如，聚（胸腺嘧啶-腺嘌呤）（polyTA）CNA-2G和聚（胸腺嘧啶-胸腺嘧啶-胞嘧啶）CNA-2G是通过将硫醇-烯杂功能二聚体与胸腺嘧啶-腺嘌呤核苷侧基聚合，将三聚体与胸腺嘧啶-胸腺嘧啶核苷侧聚而合成的。胞嘧啶核碱基。根据尺寸排阻色谱（SEC）分析，polyTA和polyTTC的数均分子量分别为2000和1800，其中包含7-8个侧链核碱基。基于CNA-2G单体和具有两个或多个侧基核碱基的CNA-2G低聚物在光聚合中的不同行为，前者观察到不寻常的硫醇-烯链状增长机理，而后者则观察到常见的硫醇-烯链状增长机理。假设不常见的硫醇链增长是依靠六元环介导的分子内氢原子转移过程。