title: [Use of high-field nulear magnetic resonance spectroscopy for the analysis of stereoselective metabolites of ibuprofen (R)-enantiomer in rat urine].
abstract: OBJECTIVE
  To study the metabolic chiral inversion and chiral metabolites of R-(-)-ibuprofen.
  
  
  METHODS
  Following administration of R-(-)-ibuprofen (250 mg.kg-1), analysis was performed on rat urine purified extracts obtained by solid phase extraction onto C-18 bonded silica gel, then the metabolites of ibuprofen were detected and identified by 1HNMR spectroscopy.
  
  
  RESULTS
  Except for a little ibuprofen, there were 2'-hydroxy-ibuprofen and its glucuronide, 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide in rat urine. 2'-hydroxy-ibuprofen is the main metabolite. 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide were diastereoisomers.
  
  
  CONCLUSIONS
  There was the phenomenon of metabolic chiral inversion, whereby the R-enantiomer is transformed in vivo to its active S-antipode via an unusual process.
authors.affiliation: Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
authors.forename: C
authors.initials: C
authors.lastname: Yang
authors.forename: W Y
authors.initials: WY
authors.lastname: He
authors.forename: M
authors.initials: M
authors.lastname: Kong
authors.forename: R M
authors.initials: RM
authors.lastname: Xu
authors.forename: S R
authors.initials: SR
authors.lastname: Zhang
authors.forename: Y K
authors.initials: YK
authors.lastname: Si
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000493:pharmacokinetics / Q000652:urine*; D005260:Female; D007052:Ibuprofen / Q000493:pharmacokinetics / Q000652:urine*; D009682:Magnetic Resonance Spectroscopy; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007052:Ibuprofen