Ethyltestosterone

Ethyltestosterone, or 17α-ethyltestosterone, also known as 17α-ethylandrost-4-en-17β-ol-3-one or 17α-pregn-4-en-17-ol-3-one, is a synthetic, orally active anabolic-androgenic steroid (AAS) of the 17α-alkylated group related to methyltestosterone that was never marketed. Like methyltestosterone, ethyltestosterone is the parent compound of many AAS. Derivatives of ethyltestosterone include norethandrolone (ethylnandrolone, ethylestrenolone), ethylestrenol (ethylnandrol), norboletone, ethyldienolone, tetrahydrogestrinone, bolenol (ethylnorandrostenol), and propetandrol.

Ethyltestosterone is described as a very weak AAS and is considerably weaker as an AAS than is methyltestosterone. Analogues with longer C17α chains such as propyltestosterone (topterone) have further greatly reduced or even antiandrogenic activity. In contrast to ethyltestosterone, its 19-demethyl variant, norethandrolone, is a potent AAS comparable in anabolic activity to testosterone propionate.