Marbofloxacin EP Impurity B Marbofloxacin EP Impurity B/10-Despiperazino-10-fluoro Marbofloxacin/9,10-Difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[3,2,1-ij][4,1,2]benzoxadiazine-6-carboxylic Acid 10-Despiperazino-10-fluoro Marbofloxacin Marbofloxacin Impurity B Marbofloxacin Impurity 2(Marbofloxacin EP Impurity B) 7H-Pyrido[3,2,1-ij][4,1,2]benzoxadiazine-6-carboxylic acid, 9,10-difluoro-2,3-dihydro-3-methyl-7-oxo- 9,10-difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de][1,3,4]-benzoxadiazine-6-carboxylicacid 9,10-Difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[3,2,1-ij][4,1,2]benzoxadiazine-6-carboxylic Acid