Fungal biotransformation of diuretic and antihypertensive drug spironolactone with Gibberella fujikuroi, Curvularia lunata, Fusarium lini, and Aspergillus alliaceus.

Derivatives of spironolactone (1), a diuretic and antihypertensive drug, were synthesized by using fungal cells for the first time. Ten different fungi were screened for their ability to biotransform 1, four of which were able to produce metabolites 2-8. Gibberella fujikuroi produced canrenone (2), 1-dehydrocanrenone (3), Curvularia lunuta provided compound 2, and 7α-thio-spironolactone (4), Fusarium lini yielded compounds 2, 3, 1β-hydroxycanrenone (5), 1α-hydroxycanrenone (6), 1-dehydro-15α-hydroxycanrenone (7), and 15α-hydroxycanrenone (8), while Aspergillus alliaceus was able to produce all the seven metabolites.