Preparation of metabolites of spironolactone by microbial oxygenation.

It has been postulated that 3-(3-oxo-7alpha-methylthio-4-androsten-17alpha-yl)propionic acid gamma-lactone (I) is a key intermediate in the metabolism of the anti-aldosterone agent, spironolactone (3-[3-oxo-7alpha-acetylthio-17beta-hydroxy-4-androsten-17alpha-yl] propionic acid gamma-lactone). In the present study it was found that microbial oxygenation of I by Chaetomium cochloides QM 624 gave three metabolites which retained sulfur in their molecules and were found to be identical to the human metabolites of spironolactone.