title: Urinary excretion of methaqualone-N-oxide in man.
abstract: 1. Oral administration of therapeutic doses (250 mg) of methaqualone (Melsed) to adult human subjects gives rise to the urinary excretion of methaqualone-N-oxide. This metabolite has been identified by chromatography and mass spectrometry and quantitatively determined by reduction with titanium trichloride to methaqualone which was then determined by g.l.c. 2. The N-oxide accounts for 5-9% of the dose in 24 h. 3. 2-Nitrobenzo-o-toluidide, a possible oxidation product of methaqualone-N-oxide, has not been detected. 4. The urinary excretion of unchanged methaqualone is less than 0-3% of the dose. The ease with which methaqualone-N-oxide is thermally converted to methaqualone casts doubts on the previously published figures for the urinary excretion of methaqualone.
mesh_terms: D000284:Administration, Oral; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008702:Methaqualone / Q000008:administration & dosage / Q000652:urine*; D010087:Oxides / Q000008:administration & dosage / Q000652:urine*
chemical_list: D010087:Oxides; D008702:Methaqualone