Summary
The metabolism of a new (β-adrenoceptor blocking agent, bufuralol, 7-ethyl-α[(tertiary butylamino)-methyl]-2-benzo-furan methanol. HC1, was studied in rat, dog and man. After oral administration of the labelled drug, 34 % of dose was eliminated in urine by the rat, 50 % by the dog, and 75 % by man. Examination of urine extracts by gas chromatographymass spectrometry with single- and multiple-ion monitoring indicated the presence of twelve metabolites. These were identified as mono-, di- and tri-oxygenated analogues of the parent drug. They had been formed from four main pathways, two involving aliphatic and two aromatic hydroxylation. All but one were present partly in conjugated and partly in free form. Three further metabolites were detected in dog urine. Two were conjugates with an unidentified hexuronic acid moiety, the third the hydroxy-acid resulting from degradation of the (3-hydroxyamine side-chain of the parent drug.
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Francis, R.J., Allen, J.G., East, P.B. et al. The metabolism of bufuralol: Urinary metabolite profiles in rat, dog and man. European Journal of Drug Metabolism and Pharmacokinetics 1, 113–124 (1976). https://doi.org/10.1007/BF03189265
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DOI: https://doi.org/10.1007/BF03189265