ABSTRACT
Disposition kinetics of ethyl biscoumacetate and its metabolite 7-hydroxy ethyl biscoumacetate were evaluated in ten healthy volunteers, after a single 300 mg oral dose of ethyl biscoumacetate. Serum concentrations of parent compound and its metabolite were measured by HPLC. The maximum serum ethyl biscoumacetate concentrations were reached 1.0-4.0 hours after drug dosing. From 3 hours after drug administration the concentration of the metabolite was always higher than the concentration of the parent compound. Geometric mean of elimination half-life was 0.66 hours for ethyl biscoumacetate and 2.03 hours for the 7-hydroxy ethyl metabolite.
Subject(s)
Ethyl Biscoumacetate/analogs & derivatives , Ethyl Biscoumacetate/pharmacokinetics , Administration, Oral , Adult , Chromatography, High Pressure Liquid , Ethyl Biscoumacetate/blood , Humans , Middle Aged , Reference ValuesABSTRACT
An efficient reversed-phase high-performance liquid chromatographic method has been developed for the determination of ethyl biscoumacetate (EBA) and its metabolite in human serum, using the mu Bondapak C18 column and methanol-water-phosphoric acid (56:46.8:0.2, v/v/v) as the mobile phase. This method permitted the determination of both EBA and a metabolite in human serum. The latter has been mentioned by other authors only in urine samples, where significant concentrations were found. Identification of the metabolite as 7-hydroxyethyl biscoumacetate was based on its chromatographic separation, followed by isolation from the eluate and direct mass spectrometric identification. It has been found that the higher EBA concentrations in human serum described by Brodie et al. [J. Pharmacol. Exp. Ther., 106 (1952) 453] were caused by the insufficient resolving power of the spectrophotometric method used, leading to overlapping of the UV spectra of the parent drug and its metabolite.
