title: Structure elucidation of a photodegradation product of ciprofloxacin.
abstract: In the photochemical degradation of ciprofloxacin, 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazinyl)-3-quinolone carboxylic acid, two major decomposition products are formed in acidic solution. The main degradation product, after both artificial and daylight exposure, was 7-amino-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-3-quinolone carboxylic acid. This product was also the dominating compound after more than 5 h irradiation with a high-pressure mercury lamp in aqueous solutions at pH < or = 2 when the solvent additionally contained water-miscible organic solvent. The structure of the isolated compound was elucidated on the basis of the chemical behaviour in thin-layer and high-performance liquid chromatography, and of information from infrared, ultraviolet, mass and nuclear magnetic resonance spectra.
authors.affiliation: Turku University Central Hospital, Hospital Pharmacy, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Torniainen
authors.forename: J
authors.initials: J
authors.lastname: Mattinen
authors.forename: C P
authors.initials: CP
authors.lastname: Askolin
authors.forename: S
authors.initials: S
authors.lastname: Tammilehto
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry* / Q000528:radiation effects; D002851:Chromatography, High Pressure Liquid; D002939:Ciprofloxacin / Q000737:chemistry* / Q000528:radiation effects; D006863:Hydrogen-Ion Concentration; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010777:Photochemistry; D014466:Ultraviolet Rays
chemical_list: D000890:Anti-Infective Agents; D002939:Ciprofloxacin