M-Sten Methylstenbolone

M-Sten is an anabolic-androgenic product based on 2,17-dimethyl-17b-hydroxy-5a-androst-1-en-3-one, a substance known as Methylstenbolone, M-Sten or Ultradol, which is a double methylated compound, structurally similar to 5α-dihydrotestosterone (DHT). M-Sten is known for having similar effects to that of S-drol. M-Sten does not convert to an estrogenic metabolite or have any affinity for the progesterone receptor, so estrogen-mediated side effects should be virtually non-existent.

M-Sten
CAS Number	6176-38-1
Molar Mass	316.485
Chemical Formula	C₂₁H₃₂O₂
IUPAC Name	(5S,8R,9S,10S,13S,14S,17S)-17-hydroxy-2,10,13,17-tetramethyl-5,6,7,8,9,11,12,14,15,16-decahydro-4H-cyclopenta[a]phenanthren-3-one