tert-butyl 7-(4-(ethoxycarbonyl)-4-methylpiperidin-1-yl)-5-oxa-2,6-diazaspiro[3.4]oct-6-ene-2-carboxylate   、                                                                                      
4-cyclobutyl-5-cyclopropyl-2-methoxybenzaldehyde                                                                                                                                                                                                                                                                                                          以the title compound was obtained in the similar manner as in Step G of Example 1的产率得到ethyl 1-(2-(4-cyclobutyl-5-cyclopropyl-2-methoxybenzyl)-5-oxa-2,6-diazaspiro[3.4]oct-6-en-7-yl)-4-methylpiperidine-4-carboxylate