Synthesis and Properties of RNA Analogues Having Amides as Interuridine Linkages at Selected Positions
作者:Eriks Rozners、Dace Katkevica、Erika Bizdena、Roger Strömberg
DOI:10.1021/ja0360900
日期:2003.10.1
oligonucleotides and RNA had stability similar to unmodified RNA-RNA duplexes (Delta t(m)= -0.2 to +0.7 degrees C per modification). However, the AM2 modification resulted in substantial stabilization of duplexes: Delta t(m)= +1 to +2.4 degrees C per modification compared to all RNA. A 2'-O-methyl vicinal to the AM2 linkage further increased the duplex stability. Our results suggest that RNA analogues having
已合成在选定位置具有酰胺核苷间键(AM1:3'-CH(2)CONH-5' 和 AM2:3'-CH(2)NHCO-5')的寡核糖核苷酸类似物,并且由这些形成的双链体的热稳定性已通过 UV 熔解实验评估了具有互补 RNA 片段的类似物。研究了两个系列的具有 2'-OH 或 2'-OMe 邻近酰胺键的低聚物。单体合成子(3' 和 5'-C 胺和羧酸)合成如下: 对于 AM1 类似物的合成,采用已知的自由基烯丙基化序列,然后是双键断裂。为了合成 AM2 类似物,开发了通过添加硝基甲烷然后将硝基官能团转化为氨基或羧基的新途径。单体胺和羧酸偶联,然后进行保护基操作和膦酰化,得到用于寡核苷酸合成的二聚体 3'-膦酸结构单元。还制备了具有 3'-酰胺和 2'-OH 或 2'-OMe 基团的单体模型化合物,并通过 (1) H NMR 确定了它们的构象平衡。AM1 和 AM2 模型对北方构象异构体表现出相同的偏好(在