5,8-dimethyl-3-trifluoromethyl-5,6,7,8-tetrahydro-1,2,4-triazolo[3,4-a]pyrazine hydrochloride   、                                                                                      
Boc-(R)-3-氨基-4-(2,4,5-三氟苯基)丁酸                                                                                                                                                              在
                                                                                                                                                                                 
N-羟基-7-氮杂苯并三氮唑   、                                                                                                  
N,N-二异丙基乙胺   、                                                                                                  N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
N,N-二甲基甲酰胺                                                                                  为溶剂,
                                                                                                                                                    反应 18.0h,
                                                                                                                生成                                                 tert-butyl [(1R)-3-[5,8-dimethyl-3-(trifluoromethyl)-5,6-dihydro-1,2,4-triazolo[4,3-a]pyrazine-7(8H)-yl]-3-oxo-1-(2,4,5-trifluorobenzyl)propyl]carbamate