{1-[(5-chloro-2,4-dimethoxy-phenylcarbamoyl)-methyl]-2,4-dioxo-1,4-dihydro-2H-pyrido[3,4-d]pyrimidin-3-yl}-acetic acid tert-butyl ester                                                                                                                                                              在
                                                                                                                                                                                 
甲醇                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二氯甲烷   、                                                                                         
三氟乙酸                                                                                  为溶剂,
                                                                                                                                                    反应 16.0h,
                                                                                                                以finally giving the title, [M+H]+ 448.93的产率得到{1-[(5-chloro-2,4-dimethoxy-phenylcarbamoyl)-methyl]-2,4-dioxo-1,4-dihydro-2H-pyrido[3,4-d]pyrimidin-3-yl}-acetic acid