Nucleoside Phosphoramidites [Nucleic Acid Synthesis]

Oligonucleic acids used as pharmaceuticals are chemically modified in various ways to improve their in vivo stability and affinity to their targets. In particular, oligonucleic acids with the 2' position methoxy groups,¹⁾ fluoro groups,²⁾ and methoxyethoxy groups³⁾ have been actively studied and used in some nucleic acid drugs that have been launched on the market. By using the corresponding nucleoside phosphoramidites and applying phosphoramidite methods, it is possible to introduce modified nucleoside units.