Dimethyltrienolone (developmental code name RU-2420) is a synthetic, orally active, and extremely potent anabolic–androgenic steroid (AAS) and 17α-alkylated 19-nortestosterone (nandrolone) derivative which was never marketed for medical use. It has among the highest known affinity of any AAS for the androgen (and progesterone) receptors, and has been said to be perhaps the most potent AAS to have ever been developed.