1-Ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(3-oxo-1-piperazinyl)-3-quinolinecarboxylic acid ; CAS # 74011-42-0 ;

1-Ethyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid ; CAS # 70458-96-7 ;

7-Chloro-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ; CAS # 68077-26-9 ;

Norfloxacin Desethylene Impurity ; Norfloxacin Ethylenediamine Analog ; 7-[(2-Aminoethyl)amino]-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid HCl ; CAS # 1797116-86-9 (HCl salt) ; 75001-77-3 (base) ;

Norfloxacin Dipiperazine Impurity ; 1-Ethyl-4-oxo-6,7-bis(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid ;

Norfloxacin Descarboxy Impurity ; 1-Ethyl-6-fluoro-7-(piperazin-1-yl)quinolin-4(1H)-one ; CAS # 75001-82-0 ;

Norfloxacin HCl 7-Chloro Analog ; 7-Chloro-1-ethyl-4-oxo-6-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid HCl ; CAS # 75001-78-4 ;

Norfloxacin 6-Chloro Analog ; 6-Chloro-1-ethyl-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid HCl ; CAS # 67681-86-1 (HCl salt) ; 67681-84-9 (base) ;

Norfloxacin N-Formyl Impurity ; 1-Ethyl-6-fluoro-7-(4-formylpiperazin-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ; CAS # 70459-04-0 ;

Norfloxacin N-Ethoxycarbonyl Impurity ; 7-[4-(Ethoxycarbonyl)piperazin-1-yl]-1-ethyl-6-fluoro-4-oxo-1,4-dihydro quinoline-3-carboxylic acid ; CAS # 105440-01-5 ;

7-Chloro-6-[4-(ethoxycarbonyl)piperazin-1-yl]-1-ethyl-4-oxo-1,4-dihydro quinoline-3-carboxylic acid ;

6,7-bis[4-(Ethoxycarbonyl)piperazin-1-yl]-1-ethyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ;

Norfloxacin USP RC K ; Norfloxacin N-Methyl Analog ; 6-Fluoro-1-methyl-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid ; CAS # 70459-07-3 (base) ; 74011-48-6 (HCl salt) ;

1-Ethyl-6-fluoro-1,4-dihydro-7-(4-hydroxy-1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid ; CAS # 109142-49-6 ;

Pefloxacin Mesylate ; 1-Ethyl-6-fluoro-1,4-dihydro-7-(4-hydroxy-1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid methylate ; CAS # 70458-95-6 (methylate salt) ; 70458-92-3 (base) ;