Pregnadiene

A pregnadiene is a diene derivative of a pregnane.

Dienes have two double bonds. The first is usually between carbon 4 and carbon 5 on ring A.

The second can be between carbons 6 and 7 on ring B:

Chlormadinone acetate (progestin)

Cyproterone acetate (antiandrogen)

Dydrogesterone (progestin)

Megestrol acetate (progestin, antineoplastic, appetite stimulant)

Canrenone (aldosterone antagonist)

Medrogestone (progestin)

The second can also be between carbons 1 and 2 on ring A:

Fluocinolone acetonide (glucocorticoid)

Triamcinolone (glucocorticoid)

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