Synthesis of Nucleobase-Functionalized Morpholino-Modified Nucleoside Monomers Through Palladium-Catalyzed Cross-Coupling Reactions
作者:Bappaditya Nandi、Sankha Pattanayak、Sibasish Paul、Surajit Sinha
DOI:10.1002/ejoc.201201384
日期:2013.3
5-iodocytidine, 8-bromoadenosine, and 8-bromoguanosine morpholino nucleosides as the key starting materials. These iodo or bromo derivatives have also been synthesized for the first time. Palladium-mediated cross-coupling reactions (Sonogashira, Suzuki, and Heck) were then employed with the halo derivatives to accomplish the substitutions. Different reaction conditions for C, A, and G were standardized to achieve
Morpholino 修饰的核苷类似物在发育生物学中具有广泛的应用。为了实现吗啉代核苷的核碱基功能化形式,首次描述了 5-取代胞苷、8-取代腺苷和 8-取代鸟苷吗啉代核苷单体的合成。该合成基于使用 5-碘胞苷、8-溴腺苷和 8-溴鸟苷吗啉代核苷作为关键起始原料。这些碘或溴衍生物也是首次合成。然后使用钯介导的交叉偶联反应(Sonogashira、Suzuki 和 Heck)与卤素衍生物一起完成取代。对 C、A 和 G 的不同反应条件进行标准化以实现转化。该策略的设计方式使得有用的 N-三苯甲基保护基团保留在最后。用于 Sonogashira、Suzuki 和 Heck 反应的催化剂组合分别是 Pd(PPh3)2Cl2·CuI、Pd(dppf)Cl2·CH2Cl2 和 Pd(OAc)2。5-碘胞苷单体和丙烯酸甲酯之间的 Heck 偶联效果很好,而使用丙烯腈,发现胞苷的环外胺形成氮杂-迈克尔加合