diisopropyl (2,3-dideoxy-5-O-dimethoxytrityl-3-aza-4acarba-β-D-glycero-pentofuranos-3-ylmethyl)phosphonate   、                                                                                      
甲基磺酰氯                                                                                                                                                              在
                                                                                                                                                                                 
吡啶                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷                                                                                  为溶剂,
                                                                                                                                                                                        以81%的产率得到diisopropyl (2,3-dideoxy-5-O-dimethoxytrityl-1-O-methanesulfonyl-3-aza-4a-carba-β-D-glycero-pentofuranos-3-ylmethyl)phosphonate