On February 6, 2003, Stankovic, Slobodan; Mitov, Slobodan; Stanojevic, Caslav published a patent.Synthetic Route of 86393-32-0 The title of the patent was A process for synthesis of antibiotic fluoroquinolonic acid derivatives. And the patent contained the following:
A simple and convenient procedure for obtaining antibiotics of fluoroquinolonic derivatives of general formula (I; where R, R2 = H, C1-4 alkyl; R1 = C1-4 alkyl, cycloalkyl such as cyclopropyl), and/or salts and hydrates thereof, in particular ciprofloxacin and norfloxacin, and is developed by amination of piperazine or piperazine derivatives (II; R = same as above) with the 6-fluoro-7-chloro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid derivative of general formula (III; R1 , R2 = same as above) in an inert solvent of pharmacopoeic purity, at risen temperature The process is characterized in lower reaction temperature, atm. pressure reaction, tech. simplicity of the procedure of purification by conversion and isolation in the form of pharmaceutically acceptable salts, increased yields, reducing cost on the procedure for industrial use, as well as pharmacopoeic purity of the product, enabled their use as the antibiotics in human and veterinary medicine. Thus, a mixture of 49.25 g 7-chloro-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, 72.25 g piperazine, and 250 cm3 of DMSO was heated for 1.5 to 2 h at 140°, cooled to 70°, treated with 985 cm3 distilled water, and then treated with 62.5 cm3 concentrated HCl with stirring and cooling. Formed suspension was filtered and the precipitate was rinsed with distilled water, suspended in water, dissolved by addition of 2 mol/dm3 HCl, treated with active charcoal, heated with stirring at 50°, and filtered. To the filtrate was added 2 mol/dm3 NaOH with stirring and cooling and the formed suspension was filtered. The precipitate was rinsed with distilled water, suspended in water with stirring, treated with 60 cm3 2 mol/dm3 HCl, heated for 30 min at 75-80°, and added to 1,750 cm3 absolute ethanol. The mixture was cooled to 0-5° and filtered, and the precipitate was rinsed three times with 30 cm3 absolute ethanol each time, and dried in vacuum drier at 80° to give 49.46 g ciprofloxacin hydrochloride monohydrate (1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-piperazinoquinoline-3-carboxylic acid hydrochloride monohydrate) as white crystals having m.p. 308-310° (decomposition) in 73% yield. The experimental process involved the reaction of 1-Cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid hydrochloride hydrate(cas: 86393-32-0).Synthetic Route of 86393-32-0
The Article related to fluoroquinolonic acid preparation antibiotic, ciprofloxacin hydrochloride monohydrate preparation antibiotic, fluoropiperazinodihydrooxoquinolinecarboxylic acid preparation antibiotic, norfloxacin preparation antibiotic and other aspects.Synthetic Route of 86393-32-0
Referemce:
Piperazine – Wikipedia,
Piperazines – an overview | ScienceDirect Topics