二碳酸二叔丁酯   、                                                                                      
5'-dimethoxytrityl N-benzoylcytidine                                                                                                                                                              在
                                                                                                                                                                                 sodium hydride                                                                                                                                  作用下,
                                                                                                                                                                                                                            生成                                                 
Carbonic acid (2R,3R,4R,5R)-2-(4-benzoylamino-2-oxo-2H-pyrimidin-1-yl)-5-[bis-(4-methoxy-phenyl)-phenyl-methoxymethyl]-4-hydroxy-tetrahydro-furan-3-yl ester tert-butyl ester   、                                                                                             Carbonic acid (2R,3S,4R,5R)-5-(4-benzoylamino-2-oxo-2H-pyrimidin-1-yl)-2-[bis-(4-methoxy-phenyl)-phenyl-methoxymethyl]-4-hydroxy-tetrahydro-furan-3-yl ester tert-butyl ester   、                                                                                             Carbonic acid (2R,3R,4R,5R)-2-(4-benzoylamino-2-oxo-2H-pyrimidin-1-yl)-5-[bis-(4-methoxy-phenyl)-phenyl-methoxymethyl]-4-tert-butoxycarbonyloxy-tetrahydro-furan-3-yl ester tert-butyl ester