3'-tert-butyldimethylsilylthymidine 5'-carboxaldehyde   、                                                                                      
3'-deoxy-5'-O-(4,4'-dimethoxytrityl)-3'-piperazinothymidine                                                                                                                                                              在
                                                                                                                                                                                 
titanium(IV) isopropylate   、                                                                                                  sodium cyanoborohydride                                                                                                                                  作用下,
                                                                                                                                                                                                                            生成                                                 1-[(2R,4S,5S)-5-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-4-[4-[[(2R,3S,5R)-3-[tert-butyl(dimethyl)silyl]oxy-5-(5-methyl-2,4-dioxopyrimidin-1-yl)oxolan-2-yl]methyl]piperazin-1-yl]oxolan-2-yl]-5-methylpyrimidine-2,4-dione