Clostebol propionate

Clostebol propionate (brand name Yonchlon), also known as 4-chlorotestosterone 17β-propionate or as 4-chloroandrost-4-en-17β-ol-3-one 17β-propionate, is a synthetic, injected anabolic-androgenic steroid (AAS) and a derivative of testosterone. It is an androgen ester – specifically, the C17β propionate ester of clostebol (4-chlorotestosterone) – and acts as a prodrug of clostebol in the body. Clostebol acetate is administered via intramuscular injection.