N2-[(2-chloro-4-fluorophenyl)sulfonyl]-N5-{[(1,1-dimethylethyl)oxy]carbonyl}-D-ornithine   、                                                                                      
三甲基硅烷化重氮甲烷                                                                                                                                                                                              以
                                                                                         
Toluol, Methanol   、                                                                                         
正庚烷                                                                                  为溶剂,
                                                                                                                                                    反应 0.5h,
                                                                                                                以to provide 1.3 g of the desired product (70%)的产率得到methyl N2-[(2-chloro-4-fluorophenyl)sulfonyl]-N5-{[(1,1-dimethylethyl)oxy]carbonyl}-D-ornithinate