Acidic metabolite of prednisolone.

The metabolic fate of the 17beta-ketol side chain of (21-3H) prednisolone was studied with an enzyme preparation from male golden hamster liver. The acidic metabolite of prednisolone was identified by mass spectrometry as 11beta, 17alpha,20epsilon-trihydroxy-3-oxo-1,4-pregnadien-21-oic acid. The enzyme showed substrate specificity, depending on the nature of substituent on the steroid nucleus.