Trenbolone undecanoate

Clinical data
Other names	Trenbolone undecylate; Estra-4,9,11-trien-17β-ol-3-one 17β-undecylate
Routes of administration	Intramuscular injection
Drug class	Androgen; Anabolic steroid; Androgen ester; Progestogen
Identifiers
IUPAC name [(8R,9S,10R,13S,14S,17S)-10,13-dimethyl-3-oxo-1,2,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-17-yl] undecanoate
Chemical and physical data
Formula	C29H41O3
Molar mass	437.644 g·mol−1
3D model (JSmol)	Interactive image
SMILES O(C(CCCCCCCCCC)=O)[C@]1CC[C@]([H])2[C@@]([H])3CCC4=CC(CCC4=C3C=C[C@@]21C)=O
InChI InChI=1S/C29H41O3/c1-3-4-5-6-7-8-9-10-11-28(31)32-27-17-16-26-25-14-12-21-20-22(30)13-15-23(21)24(25)18-19-29(26,27)2/h18-20,25-26H,3-17H2,1-2H3/t25-,26+,29+/m1/s1 Key:DTHSGQSBBRPTMW-ALTZYDRJSA-N

Trenbolone undecanoate, or trenbolone undecylate, is a synthetic and injected anabolic–androgenic steroid (AAS) and a derivative of nandrolone (19-nortestosterone) which was never marketed.^[1][2] It is the C17β undecanoate (undecylate) ester and a long-acting prodrug of trenbolone.^[1][2] The drug was described by Roussel Uclaf in 1967 and was the first long-lasting ester of trenbolone to be developed.^[1][2] Subsequently, trenbolone hexahydrobenzylcarbonate, a roughly equivalent compound, was developed and introduced for use in humans in 1980, though it was discontinued in 1997.^[2] Trenbolone enanthate is another long-lasting ester of trenbolone.^[2] Similarly to trenbolone undecanoate, it was never marketed, but it has been sold on the black market as a designer steroid for bodybuilders and athletes.^[2]