Epoxide-diol metabolic pathway of cytenamide in the rat.

Cytenamide administered intraperitoneally to rats is biotransformed to cytenamide-10,11-epoxide and 10,11-dihydro-10,11-dihydroxycytenamide. These metabolites were separated by chromatographic methods and their structures elucidated by mass spectrometry. The structure of the epoxide was confirmed by direct comparison with an authentic sample. The formation of a chemical artifact, cytenamide-syn-11-hydroxylactone, in the urine was observed. The formation of these metabolites in vitro was demonstrated by incubation of cytenamide with rat liver microsomes.