tert-butyl [1-(4-formyl-3-methoxyphenyl)piperidin-4-yl]carbamate   、                                                                                      4,5-diamino-2-cyclohexyl-6-methylpyridazin-3(2H)-one                                                                                                                                                              在
                                                                                                                                                                                 sulfur                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
5,5-dimethyl-1,3-cyclohexadiene                                                                                  为溶剂,
                                                                                                                                                    反应 1.0h,
                                                                                                                以60%的产率得到tert-butyl {1-[4-(6-cyclohexyl-4-methyl-7-oxo-6,7-dihydro-1H-imidazo[4,5-d]pyridazin-2-yl)-3-methoxyphenyl]piperidin-4-yl}carbamate