Spirolactone

Spirolactones are a class of functional group in organic chemistry featuring a cyclic ester attached spiro to another ring system.

The name is also used to refer to a class of synthetic steroids, called steroid-17α-spirolactones, 17α-spirolactosteroids, or simply 17α-spirolactones, which feature their spirolactone group at the C17α position.

[1][3][6] The spirolactones were developed by G. D. Searle & Company in the 1950s and thereafter and were denoted as "SC" compounds (e.g., SC-9420 for spironolactone).

[1][5] The spirolactones include the marketed drugs spironolactone (SC-9420; Aldactone), canrenone (SC-9376; Cantaren, Luvion), potassium canrenoate (SC-14266; Venactone, Soldactone), eplerenone (SC-66110, CGP-30083; Inspra), and drospirenone (ZK-30595; Yasmin).

Oxprenoate potassium (RU-28318) is not a spirolactone by definition but is a closely related antimineralocorticoid that was never marketed.