MOHN is non-aromatizable due to the presence of a hydroxy group at the C4 position, and for this reason, poses no risk of estrogenicside effects like gynecomastia at any dosage, unlike many other AAS.[1]5α-Reduction is also inhibited by the C4 hydroxy group of MOHN and, because of this, MOHN may have a relatively higher ratio of androgenic to anabolic activity than other nandrolone derivatives (as 5α-reduction, opposite to the case of most other AAS, decreases AAS potency for most nandrolone derivatives).[1] Early assays found that MOHN had approximately 13 times the anabolic activity and 3 times the androgenic activity of methyltestosterone.[1]
MOHN is the 4-hydroxylated derivative of normethandrone (17α-methyl-19-nortestosterone), the 17α-methylated derivative of oxabolone (4-hydroxy-19-nortestosterone), the 4-hydroxylated and 17α-methylated derivative of nandrolone (19-nortestosterone), and the 19-demethylated analogue of oxymesterone (4-hydroxy-17α-methyltestosterone).[1]
^Di Pietro S, Salvadori B (1964). "Sperimentazione Clinica del 4-Idrossi-17-alfa-metil-19-nortestosterone nel Carcinoma Mammario Diffuso" [Clinical Trial with 4-Hydroxy-17α-methyl-19-nortestosterone in Advanced Breast Cancer]. Tumori (in Italian). 50 (6): 445–456. doi:10.1177/030089166405000602. ISSN0300-8916. PMID14261594. S2CID208183701.