title: Stereospecific and simultaneous high-performance liquid chromatographic assay of flosequinan and its metabolites in human plasma.
abstract: A high-performance liquid chromatographic method was developed for the simultaneous determination of the enantiomers of flosequinan [(+/-)-7-fluoro-1-methyl-3-methylsulphinyl-4-quinolone] and its metabolites, flosequinan sulphide and sulphone, in human plasma. These compounds were extracted from plasma with chloroform. The compounds were separated on a chiral stationary phase of cellulose tris-3,5- dimethylphenylcarbamate coated on silica gel, with a mobile phase of ethanol-methanol (22:78, v/v). Flosequinan enantiomers and flosequinan sulphone were determined by UV detection at a wavelength of 320 nm. Flosequinan sulphide was determined using fluorescence detection (excitation at 370 nm, emission at 430 nm). Standard curves were linear over the concentration range 5-10,000 ng/ml for both enantiomers and flosequinan sulphide, and 20-10,000 ng/ml for flosequinan sulphone. This method is adequate for pharmacokinetic studies of the enantiomers of flosequinan and its metabolites.
authors.affiliation: Department of Drug Metabolism, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan.
authors.forename: E
authors.initials: E
authors.lastname: Kashiyama
authors.forename: M
authors.initials: M
authors.lastname: Odomi
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D011804:Quinolines / Q000097:blood* / Q000493:pharmacokinetics; D012680:Sensitivity and Specificity; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D013440:Sulfides / Q000097:blood; D013450:Sulfones / Q000097:blood
chemical_list: D011804:Quinolines; D013440:Sulfides; D013450:Sulfones; C047316:flosequinan