5-bromo-7-(2-deoxy-β-D-erythro-pentofuranosyl)-4-[(1-dimethylaminoethylidene)amino]-2-[(diphenylcarbamoyl)oxy]-7H-pyrrolo[2,3-d]pyrimidine 在
吡啶 、
N,N-二异丙基乙胺 作用下,
以
二氯甲烷 为溶剂,
反应 5.5h,
生成 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