benzoic acid 5-(S)-benzyloxycarbonylamino-2-(S)-[(1-(S)-tert-butoxycarbonyl-cyclohexyl-methyl)-carbamoyl]-4-oxo-6-phenyl-hexyl ester   、                                                                                      
三氟乙酸                                                                                                                                                              在
                                                                                                                                                                                 palladium 10% on activated carbon   、                                                                                                  
氢气                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
甲醇                                                                                  为溶剂,
                                                                                                                                                                                        以63%的产率得到benzoic acid 5-(S)-amino-2-(S)-[(1-(S)-carboxy-cyclohexyl-methyl)-carbamoyl]-4-oxo-6-phenyl-hexyl ester trifluroacetate