Dimethyltrienolone (developmental code name RU-2420) is a synthetic, orally active, and extremely potent anabolicâÂÂandrogenic steroid (AAS) and 17ñ-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.
Dimethyltrienolone is an extremely potent agonist of the androgen and progesterone receptors and hence AAS and progestogen. In animal bioassays, it was shown to possess more than 100 times the anabolic and androgenic potency of the reference AAS methyltestosterone. The drug is not a substrate for 5ñ-reductase and so is not potentiated or inactivated in so-called "androgenic" tissues like the prostate gland or skin. It is also not a substrate for aromatase and so has no estrogenic activity. Due to its lack of estrogenicity, dimethyltrienolone has no propensity for causing estrogenic side effects like gynecomastia. Because of its C17ñ methyl group and very high resistance to hepatic metabolism, dimethyltrienolone is said to be exceedingly hepatotoxic.
Dimethyltrienolone, also known as 7ñ,17ñ-dimethyl-ô<sup>9,11</sup>-19-nortestosterone or as 7ñ,17ñ-dimethylestra-4,9,11-trien-17ò-ol-3-one, as well as 7ñ,17ñ-dimethyltrenbolone, is a synthetic estrane steroid and a 17ñ-alkylated derivative of nandrolone (19-nortestosterone). It is the 7ñ,17ñ-dimethyl derivative of trenbolone and the 7ñ-methyl derivative of metribolone, as well as the ô<sup>9,11</sup> analogue of metribolone and the ô<sup>9,11</sup>, 17ñ-methylated derivative of trestolone.
Dimethyltrienolone can be congenially prepared from almestrone.
Dimethyltrienolone was first described in 1967. It was never marketed for medical use.