title: The biliary excretion of acenocoumarol in the rat: stereochemical aspects.
abstract: Within 24 h, 50% of a single dose of the acenocoumarol enantiomers was recovered in bile and 20% in urine of Wistar rats. The elimination products were mainly (greater than 90%) the 6- and 7-hydroxyacenocoumarol as conjugates in the bile but free in the urine. Only R-acenocoumarol, free and conjugated, was excreted in bile. There were no gross differences between the enantiomers in metabolic pattern or in the amount of metabolites formed. A significant difference was observed for the biliary excretion of the 7-hydroxy metabolite; the ratio of free and conjugated 7-hydroxyacenocoumarol was three times higher for the S- than for the R-isomer. An unknown third metabolite was recovered in bile in higher amounts with the S- than with the R-acenocoumarol. Only traces of this metabolite were recovered from urine. The data show an extensive biliary excretion of acenocoumarol and demonstrate stereoselective mechanisms in the excretion processes.
mesh_terms: D000074:Acenocoumarol / Q000378:metabolism* / Q000652:urine; D000818:Animals; D001646:Bile / Q000378:metabolism*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002851:Chromatography, High Pressure Liquid; D008968:Molecular Conformation; D051381:Rats; D013237:Stereoisomerism
chemical_list: D000074:Acenocoumarol