2-isothiocyanato-3,5-dimethylpyrazine   、                                                                                      
methyl 3-amino-4-chloro-2-[(3-hydroxypropyl)amino]benzoate                                                                                                                                                              在
                                                                                                                                                                                 silica gel   、                                                                                                  
ethyl acetate n-hexane                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
四氢呋喃                                                                                  为溶剂,
                                                                                                                                                    反应 6.0h,
                                                                                                                以to give methyl 4-chloro-3-{[(3,5-dimethylpyrazin-2-yl)carbamothioyl]amino}-2-[(3-hydroxypropyl)amino]benzoate as a yellow solid (430 mg)的产率得到methyl 4-chloro-3-{[(3,5-dimethylpyrazin-2-yl)carbamothioyl]amino}-2-[(3-hydroxypropyl)amino]benzoate