N4,N6-Bis((di-n-butylamino)methylene)-1-[2-deoxy-β-D-erythro-pentofuranosyl]-1H-pyrazolo[3,4-d]-pyrimidin-4,6-diamine   、                                                                                      
N4,N6-Bis(benzoyl)-1-[2-deoxy-5-O-(4,4'-dimethoxytrityl)-β-D-erythro-pentofuranosyl]-1H-pyrazolo[3,4-d]-pyrimidin-4,6-diamine                                                                                                                                                                                              以
                                                                                         
吡啶                                                                                  为溶剂,
                                                                                                                                                                                        以85 mg (77%)的产率得到1-[2-Deoxy-5-O-(4,4'-dimethoxytrityl)-β-D-erythro-pentofuranosyl]-N4-((di-n-butylamino)methylene)-N6-formyl-1H-pyrazolo[3,4-d]-pyrimidin-4,6-diamine