7-(8-ethyl-7-fluoro-3-(methoxymethoxy)naphthalen-1-yl)-8-fluoro-2-(((2R,7aS)-2-fluorotetrahydro-1H-pyrrolizin-7a(5H)-yl)methoxy)pyrido[4,3-d]pyrimidin-4-ol   、                                                                                      
(R)-5-methyl-1,4-oxazepane hydrochloride                                                                                                                                                              在
                                                                                                                                                                                 
N,N-二异丙基乙胺   、                                                                                                  N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
N,N-二甲基乙酰胺                                                                                  为溶剂,
                                                                                                                                                                                        以52 %的产率得到(R)-4-(7-(8-ethyl-7-fluoro-3-(methoxymethoxy)naphthalen-1-yl)-8-fluoro-2-(((2R,7aS)-2-fluorotetrahydro-1H-pyrrolizine-7a(5H)-yl)methoxy)pyrido[4,3-d]pyrimidin-4-yl)-5-methyl-1,4-oxazepane