乙酸酐   、                                                                                      
2-amino-3,4-dihydro-5-hydroxyiminomethyl-3-methoxymethyl-7-(2,3-O-isopropylidene-β-D-ribofuranosyl)-7H-pyrrolo<2,3-d>pyrimidin-4-one                                                                                                                                                                                                                                                                      反应 2.5h,
                                                                                                                以90%的产率得到5-cyano-2-diacetylamino-3,4-dihydro-3-methoxymethyl-7-(5-O-acetyl-2,3-O-isopropylidene-β-D-ribofuranosyl)-7H-pyrrolo<2,3-d>pyrimidin-4-one