We showcase the high potential of the 2′-cyanoethoxymethyl (CEM) methodology to synthesize RNAs with naturally occurring modified residues carrying stable isotope (SI) labels for NMR spectroscopic applications. The method was applied to synthesize RNAs with sizes ranging between 60 to 80 nucleotides. The presented approach gives the possibility to selectively modify larger RNAs (>60 nucleotides) with atom-specifically ¹³C/¹⁵N-labelled building blocks. The method harbors the unique potential to address structural as well as dynamic features of these RNAs with NMR spectroscopy but also using other biophysical methods, such as mass spectrometry (MS), or small angle neutron/X-ray scattering (SANS, SAXS).

中文翻译：

---

长稳定同位素标记的RNA的化学合成和NMR光谱

我们展示了2'-氰基乙氧基甲基（CEM）方法的巨大潜力，可以合成带有稳定同位素（SI）标记的天然存在的修饰残基的RNA，用于NMR光谱学应用。该方法用于合成大小在60至80个核苷酸之间的RNA。提出的方法提供了用原子特异性¹³ C / ¹⁵ N标记的构建基选择性修饰较大的RNA（> 60个核苷酸）的可能性。该方法具有利用NMR光谱处理这些RNA的结构和动态特征的独特潜力，而且还可以使用其他生物物理方法，例如质谱（MS）或小角度中子/ X射线散射（SANS，SAXS）。