1-cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-1,4-dihydro-3-quinoline carboxylic acid (O
3,O
4)bis(acyloxy-O)borate 、
N,N-二甲基(R-吗啉-2-基)甲酰胺 在
三乙胺 作用下,
以39%的产率得到(S)-1-cyclopropyl-1,4-dihydro-7-[2-(N,N-dimethylaminomethyl)morpholino]-6-fluoro-8-methoxy-4-oxoquinoline-3-carboxylic acid