重氮甲烷 、
(+/-)-7-(2-carboxypiperidin-1-yl)-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid 以
乙醚 为溶剂,
以85%的产率得到(+/-)-methyl 1-cyclopropyl-6-fluoro-7-[2-(methoxycarbonyl)piperidin-1-yl]-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylate