5-chloro-7-(2-deoxy-β-D-erythro-pentofuranosyl)-4-methoxy-2-(methylthio)-7H-pyrrolo<2,3-d>pyrimidine                                                                                                                                                              在
                                                                                                                                                                                 
sodium hydroxide                                                                                                                                  作用下,
                                                                                                                                                                                        反应 3.0h,
                                                                                                                以78%的产率得到5-chloro-7-(2-deoxy-β-D-erythro-pentofuranosyl)-3,7-dihydro-2-(methylthio)-4H-pyrrolo<2,3-d>pyrimidin-4-one