3-Aminopiperid-2-one, an unusual metabolite in the urine of a patient with hyperammonaemia, hyperornithinaemia and homocitrullinuria.

The urine of a patient with a disorder characterized by hyperammonaemia, hyperornithinaemia and homocitrullinuria contains abnormal amounts of 3-aminopiperid-2-one. The properties of this compound closely resemble those ascribed previously (Gordon, B.A., Gatfield, P.D. and Taller, E. (1977) Clin. Biochem. 10, 78-82) to ornithine methyl ester. The excretion of the aminopiperidone ranged from 130-1050 micronmol/g creatinine.