(2-cyanoethoxy)-(N,N-ethylmethylamino)chlorophosphoramidite 、
5'-O-[双(4-甲氧基苯基)苯基甲基]-2'-O-[(叔丁基)二甲基硅基]-N-(2-甲基-1-氧代丙基)鸟苷 在
N,N-二异丙基乙胺 作用下,
反应 0.5h,
以73%的产率得到N-isobutyryl-5'-O-(4,4'-dimethoxytrityl)-2'-O-TBDMS-guanosine-3'-O-[O-(2-cyanoethyl)-N,N-ethylmethylphosphoramidite]