(3S,5S)-4-(3-tert-butoxycarbonylamino-5-isopropyl-2,4-dioxopyrrolidin-3-yl)-but-2-enoic acid ethyl ester   、                                                                                      
苄胺                                                                                                                                                                                              以
                                                                                         
乙醇                                                                                  为溶剂,
                                                                                                                                                    反应 96.0h,
                                                                                                                以70%的产率得到(3S,3aS,4R,5S,6aS)-ethyl 5-(benzylamino)-6a-(tert-butoxycarbonylamino)-3a-hydroxy-3-isopropyl-1-oxooctahydrocyclopenta[c]pyrrole-4-carboxylate