TY - JOUR T1 - Hopantenic acid beta-glucoside as a new urinary metabolite of calcium hopantenate in dogs. JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 740 LP - 745 VL - 14 IS - 6 AU - K Nakano AU - H Ando AU - Y Sugawara AU - M Ohashi AU - S Harigaya Y1 - 1986/11/01 UR - http://dmd.aspetjournals.org/content/14/6/740.abstract N2 - The metabolism of calcium hopantenate (HOPA) was studied in beagle dogs. After oral administration of 14C-labeled HOPA, 25.5% of the administered radioactivity was excreted in the urine within 24 hr, mostly in the form of unchanged drug. The only metabolite, accounting for 4.2% of the radioactivity in the urine, was isolated by HPLC. The metabolite was hydrolyzed by the treatment of beta-glucuronidase (Helix pomatia), acid phosphatase, or beta-glucosidase. These enzyme activities were not inhibited by treatment with D-glucaric acid 1,4-lactone or PO4(3-), but with D-gluconic acid 1,5-lactone, demonstrating that the metabolite is a glucose conjugate. The compound was identified as HOPA-glucoside, 4'-O-(beta-D-glucopyranosyl)-D-hopantenic acid, by GC/MS analyses after derivatization of the metabolite and the synthetic compound. This is the first reported instance of glucose conjugation to a non-acidic hydroxyl group in the metabolism of xenobiotics in mammals. ER -