Preparation and Stability in Solution of Androstenedione 3-Enol Glucosiduronate

4-14C-Androstenedione 3-enol glucosiduronate (14C-AEG) was synthesized and its stability was studied by analyzing liberated steroids. Incubation of 14C-AEG with human urine at 37° for 48 hr resulted in 49% hydrolysis. 14C-AEG was fairly stable in neutral and basic media, but rapidly hy rolyzed at acidic pH. 14C-AEG was solvolyzed almost quantitatively with acidic ethyl acetate in the same way as steroid sulfates. By incubation with β-glucuronidase (Ketodase, Helix pomatia, and bacterial β-glucuronidase) at pH 6.2 for 3 hr, 64-71% of 14C-AEG was hydrolyzed. Hydrolysis with Helix pomatia β-glucuronidase was inhibited by D-glucaro-(1→4)-lactone. Analyses of liberated steroids by TLC revealed the formation of artifacts (polar steroids) in all cases so far examined. One of them was identified as 6β-hydroxyandrostenedione.