TY - JOUR T1 - N-METHYLATION, A NEWLY IDENTIFIED PATHWAY IN THE DOG FOR THE METABOLISM OF OXPRENOLOL, A β-RECEPTOR BLOCKING AGENT JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 565 LP - 568 VL - 1 IS - 3 AU - G. A. LEESON AU - D. A. GARTEIZ AU - W. C. KNAPP AU - G. J. WRIGHT Y1 - 1973/05/01 UR - http://dmd.aspetjournals.org/content/1/3/565.abstract N2 - Oxprenolol, 1-(o-allyloxyphenoxy)-3-isopropylamino-2-propanol. is a β-receptor blocking agent. In this communication, we report a previously unrecognized metabolic pathway for oxyprenolol in dogs, N-methylation. Tritium-labeled oxprenolol, 5 mg/kg, was administered to beagle dogs. Urine samples were incubated with β-glucuronidase, alkalinized, and extracted with benzene. Using gas chromatograph/mass spectrometer techniques. 1-(o-allyloxyphenoxy)-3-methylamino-2-propanol was identified after administration of oxprenolol. This compound also was identified after administration of 0.5 mg/kg of 1-(o-allyloxyphenoxy)-3-amino-2-propanol. Thus, it appears that oxprenolol in the dog is N-dealkylated and an N-methylation then occurs. Copyright © 1973 by The American Society for Pharmacology and Experimental Therapeutics ER -