title: Isolation and identification of the C6-hydroxy and C20-hydroxy metabolites and glucuronide conjugate of methylprednisolone by preparative high-performance liquid chromatography from urine of patients receiving high-dose pulse therapy.
abstract: In the present study metabolites of methylprednisolone were detected using gradient elution high-performance liquid chromatography. Separation was performed by a Cp Spherisorb ODS 5 microm (250 mmx4.6 mm I.D.) column, connected to a guard column, packed with pellicular reversed phase. The mobile phase was a mixture of acetonitrile and 1% acetic acid in water. At t = 0, this phase consisted of 2% acetonitrile and 98% acetic acid 1% in water (v/v). During the following 35 min the phase changed linearly until it attained a composition of acetonitrile-buffer (50:50, v/v). At 40 min (t = 40) the mobile phase was changed over 5 min to the initial composition, followed by equilibration during 2 min. The flow-rate was 1.5 ml/min. UV detection was achieved at 248 nm. We have isolated the respective compounds with the most abundant concentration and suggested their chemical structure based on NMR, IR, UV, MS, retention behaviour and melting points. The c/, stereochemistry could not be solved in this study. The overall picture of the metabolic pathways of methylprednisolone is apparently simple: reduction of the C20 carbonyl group and further oxidation of the C20-C21 side chain (into C21-COOH and C20-COOH), in competition with or additional to the oxidation at the C6-position.
authors.affiliation: Institute of Anaesthesiology, Academic Hospital Nijmegen Sint Radboud, The Netherlands. T.Vree@anes.azn.nl
authors.forename: T B
authors.initials: TB
authors.lastname: Vree
authors.forename: C P
authors.initials: CP
authors.lastname: Verwey-van Wissen
authors.forename: A J
authors.initials: AJ
authors.lastname: Lagerwerf
authors.forename: A
authors.initials: A
authors.lastname: Swolfs
authors.forename: R A
authors.initials: RA
authors.lastname: Maes
authors.forename: R D
authors.initials: RD
authors.lastname: van Ooijen
authors.forename: O R
authors.initials: OR
authors.lastname: van Eikema Hommes
authors.forename: P J
authors.initials: PJ
authors.lastname: Jongen
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D008775:Methylprednisolone / Q000008:administration & dosage / Q000378:metabolism / Q000652:urine*; D009103:Multiple Sclerosis / Q000188:drug therapy / Q000652:urine; D013057:Spectrum Analysis
chemical_list: D008775:Methylprednisolone