[On the metabolism of antipyrine (phenazone) in man (author's transl)].

The metabolism of antipyrine (phenazone) was studied by means of C14-antipyrine labelled at C-3. Besides the metabolites already known two conjugates were isolated and characterized by their mass spectra. The occurrence of 2-hydroxymethyl-3-methyl-1-phenyl-3-pyrazolin-5-one and 3,4-dihydroxy-2,3-dimethyl-1-phenyl-pyrazolidin-5-one could not be confirmed, although 95% of the radioactivity administered was recovered.