1-[2'-O-methyl-4'-C-trifluoroacetylaminomethyl-5'-(4,4'-dimethoxytrityl)-β-D-ribofuranosyl]-N4-Isobutyrylcytosine   、                                                                                      
2-氰乙基N,N-二异丙基氯亚磷酰胺                                                                                                                                                              在
                                                                                                                                                                                 
N,N-二异丙基乙胺                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                    反应 0.67h,
                                                                                                                以51%的产率得到1-{2'-O-methyl-3'-O-[2-cyanoethoxy(diisopropylamino)phosphino]-4'-C-trifluoroacetylaminomethyl-5'-(4,4'-dimethoxytrityl)-β-D-ribofuranosyl}-N4-Isobutyrylcytosine