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. They are antimineralocorticoids, or antagonists of the mineralocorticoid receptor, and have been employed clinically as potassium-sparing diuretics. Some also possess progestogenic and/or antiandrogen properties, which have both contributed to side effects and been utilized for medical indications. The spirolactones were developed by G. D. Searle & Company in the 1950s and thereafter and were denoted as "SC" compounds.
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