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Formation of 2-(4-chlorophenoxy)-2- methylpropanamide from a clofibrate metabolite during extraction of urine
Abstract:
Drug isolation from urine by solvent extraction after alkalinization suffers the potential disadvantage of chemically altering desired isolates by hydrolytic reactions. This paper reports a reaction which results in the formation of an amide substance when urine from individuals ingesting clofibrate is treated with ammonium hydroxide or sodium hydroxide and ammonium ion. The amide formed in urine has been compared to synthetically prepared 2-(4-chlorophenoxy)-2-methylpropanamide by gas chromatography, thin layer chromatography, ultraviolet spectrophotometry, infrared spectrophotometry, and mass spectrometry with complete correspondence of chemical properties. Conditions under which this amide, the major clofibrate-related entity, formed in urine are those routinely employed in analytical toxicology.
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