7-(2-(4-Ethyl-2,3-dioxopiperazinylcarbonylamino)-2-(p-hydroxyphenyl)acetamido)cephalosporanic acid   、                                                                                      
1-甲基-5-巯基-1H-四氮唑                                                                                                                                                                                              以
                                                                                         
硝基甲烷                                                                                  为溶剂,
                                                                                                                                                                                        生成                                                 3-(((1-methyl-1H-tetrazol-5-yl)thio)methyl)-7-(2-(4-ethyl-2,3-dioxopiperazinylcarbonylamino)-2-(p-hydroxyphenyl)acetamido)-3-cephem-4-carboxylic acid