Methenolone acetate, an anabolic-androgenic steroid, undergoes several metabolic transformations in the body. Here are its key metabolites and metabolic pathways:
1.Ester Hydrolysis:
The acetate ester is cleaved by esterases, releasing the active form, methenolone (also known as Primobolan).
2.Phase I Metabolism (Oxidation, Reduction, Hydroxylation):
●6β-Hydroxylation: A major metabolic pathway, producing 6β-hydroxymethenolone. This metabolite is often a primary marker in doping tests.
●Reduction of the 1,2 Double Bond: The double bond in methenolone's structure may be reduced, forming dihydromethenolone.
●17β-Hydroxy Oxidation: Oxidation of the 17β-hydroxy group to a 17-keto group, yielding 17-keto-methenolone.
●Other potential hydroxylation sites include the 16α/16β positions, though these are less documented.
3.Phase II Metabolism (Conjugation):
The phase I metabolites undergo glucuronidation or sulfation to enhance water solubility for excretion. Major conjugated metabolites include:
●6β-hydroxymethenolone glucuronide
●Dihydromethenolone glucuronide
●17-keto-methenolone glucuronide
4.Excretion:
These conjugated metabolites are primarily excreted in urine, with glucuronides being the dominant form detected in doping analyses.
Summary of Key Metabolites:
●Methenolone (post-ester hydrolysis)
●6β-Hydroxymethenolone (major oxidative metabolite)
●Dihydromethenolone (reduced form)
●17-Keto-methenolone (oxidized form)
Conjugated derivatives (glucuronides/sulfates) of the above compounds
These metabolites are critical for detecting methenolone acetate use in anti-doping and clinical settings.
