Methasterone (nickname Superdrol), also known as methyldrostanolone, is an orally active anabolic-androgenic steroid (AAS) that was never marketed through legitimate channels for medicinal purposes. It was brought to market, instead, in a clandestine fashion as a "designer steroid." Mebolazine is formed by hydrazone formation between 2 equivalents of methasterone with 1 equivalent of hydrazine.

Methyldrostanolone Methasterone Superdrol Functions & Traits
Superdrol is an anabolic androgenic steroid comprised of the active steroidal hormone Methyldrostanolone. This is a dihydrotestosterone (DHT) derived anabolic steroid or more specifically a structurally altered form of Drostanolone. Superdrol is simply the Drostanolone hormone with an added methyl group at the 17th carbon position that allows the hormone to survive oral ingestion and officially classifies it as a C17-alpha alkylated (C17-aa) anabolic steroid. It also carries an added methyl group at the carbon two position, which greatly increases its anabolic power. These slight alterations will also reduce Superdrol's androgenicity compared to Masteron, which isn't all that androgenic to begin with.
On a structural basis, Superdrol carries an anabolic rating of 400; nearly four times that of Masteron. It will also carry an androgenic rating of 20, which is extremely mild. This is a non-aromatizing anabolic steroid carrying no estrogenic or progesterone activity.