4-(2,3-Dihydrobenzo[b][1,4]dioxin-6-yl)butanoic acid hydrochloride   、                                                                                      
(2S,4R)-4-benzyl-N-(4-(4-fluorophenoxy)phenyl)pyrrolidine-2-carboxamide                                                                                                                                                                                                                                                                                                          以gave Compound 33, (2S,4R)-4-benzyl-1-(4-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)butanoyl)-N-(4-(4-fluorophenoxy)phenyl)pyrrolidine-2-carboxamide (8.4 mg, 23.5%)的产率得到