乙酸酐 、
2',3'-O-isopropylidene-5'-O-methoxymethyl-6-phenylhydroxymethyluridine 在
吡啶 作用下,
以97.5%的产率得到Acetic acid [3-((3aR,4R,6R,6aR)-6-methoxymethoxymethyl-2,2-dimethyl-tetrahydro-furo[3,4-d][1,3]dioxol-4-yl)-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidin-4-yl]-phenyl-methyl ester