[Metabolism of enantiomers of the cytostatic ifosfamide].

3H-labelled enantiomers of the cytostatic drug ifosfamide isolated by chromatographic resolution, were intraperitoneally applied to female NMRI mice. The concentrations of ifosfamide and its metabolites in blood and urine were determined. Both enantiomers of ifosfamide are eliminated at almost equal rates. The metabolites with anticancer activity are formed to a greater extent, 4-ketoifosfamide is formed stereoselectively from S(-)-ifosfamide. In vivo the conversion of aldo- to 4-hydroxyifosfamide does not take place.