5-bromo-7-[2-deoxy-5-O-(4,4'-dimethoxytriphenylmethyl)-β-D-erythro-pentofuranosyl]-4-[(1-dimethylaminoethylidene)amino]-2-[(diphenylcarbamoyl)oxy]-7H-pyrrolo[2,3-d]pyrimidine 、
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 0.5h,
以90%的产率得到5-bromo-7-[2-deoxy-5-O-(4,4'-dimethoxytriphenylmethyl)-β-D-erythro-pentofuranosyl]-4-[(1-dimethylaminoethylidene)amino]-2-[(diphenylcarbamoyl)oxy]-7H-pyrrolo[2,3-d]pyrimidine 3'-(2-cyanoethyl)-N,N-diisopropylphosphoramidite