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.

摘要: 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 μm (250 mm×4.6 mm I.D.) column, connected to guard packed with pellicular reversed phase. The mobile phase mixture acetonitrile and 1% acetic acid in water. At t =0, this consisted 2% 98% water (v/v). During following 35 min changed linearly until it attained composition acetonitrile–buffer (50:50, v/v). 40 ( =40) over initial composition, followed equilibration during 2 min. flow-rate 1.5 ml/min. UV detection achieved at 248 nm. We have isolated respective compounds most abundant concentration suggested their chemical structure based on NMR, IR, UV, MS, retention behaviour melting points. α/β stereochemistry could not be solved study. overall picture metabolic pathways is apparently simple: reduction C20 carbonyl group further oxidation C20-C21 side chain (into C21-COOH C20-COOH), competition or additional C6-position.