3-methyl-3,7-diazabicyclo[3.3.0]oct-1(5)-ene dihydrobromide 、
1,8-二氮杂双环[5.4.0]十一碳-7-烯 、
左旋氧氟沙星羧酸 以
乙腈 为溶剂,
以70%的产率得到(-)-9-fluoro-3(S)-methyl-10-[7-methyl-3,7-diazabicyclo[3.3.0]oct-1(5)-en-3-yl]-7-oxo-2,3-dihydro-7H-pyrido[1.2.3-de]-1,4-benzoxazine-6-carboxylic acid