Bolandiol

Bolandiol (INN, also known as 19-nor-4-androstenediol, estr-4-ene-3β,17β-diol, or 3β-dihydronandrolone) is an anabolic-androgenic steroid (AAS) that was never marketed. However, a dipropionate ester derivative, bolandiol dipropionate, has been marketed. Bolandiol and its dipropionate ester are unique among AASs in that they reportedly also possesses estrogenic and progestogenic activity.

Bolandiol is on the World Anti-Doping Agency's list of prohibited substances, and is therefore banned from use in most major sports. It is a potential metabolic precursor to nandrolone. However, several clinical studies have concluded that bolandiol does not alter strength, body composition, or exercise performance.