6-fluoro-7-(4-aminosulfonylphenyl)-1-ethyl-1,4-dihydroquinol-4-one 3-carboxylic acid 、
Ethyl 6,8-difluoro-7-(4-aminosulfonylphenyl)-1-ethyl-1,4-dihydroquinol-4-one 3-carboxylate 在
sodium hydroxide 作用下,
以
乙醇 为溶剂,
以84%的产率得到6,8-Difluoro-7-(4-aminosulfonylphenyl)-1-ethyl-1,4-dihydroquinol-4-one 3-carboxylic acid