Anabolic/androgenic ratio

Nortestosterone. 1 -Methyl-A -3-desoxo-5a-dihydro 17-acetate (N-64), la-methyl 5a-dihydro (N-48), la-methyl 5a-dihydro 17-acetate (N-61), la-hydroxy 5a-dihydro 17-acetate (N-62), la,2a-methylene 5a-dihydro 17-acetate (N-63), and la-methyl-A -5a-dihydro 17-acetate (N-65) substitutions all markedly decrease the androgenic activity while the anabolic activity is decreased in a smaller degree. The anabolic-androgenic ratio becomes favorable. 

Testosterone. Ij8-Methyl 17-acetate (S-73) and 1/3-acetylthio 17-ketone (S-38) substitutions give a marked decrease in the androgenic activity. The anabolic activity of the first compound is slightly decreased and that of the second compound markedly decreased. The anabolic-androgenic ratio of S-73 is favorable. 

D-IOl), and 1/8-methyl 17a-methyl (D-124) substitutions all markedly decrease the androgenic potency, while the anabolic potency is decreased only to a smaller degree. Hence the anabolic-androgenic ratio becomes favorable. 

As already outlined under 2a-substitution, 2a,3a-epoxy 17-acetate (D-37), 2a ,3a-methylene (D-40), 2a,3a-epithio (D-69), 2o ,3a -difluoro-methylene 17-acetate (D-51), and, in addition, 3a,4a-epoxy 17-acetate (D-39) substitutions all give increased androgenic as well as anabolic activity, with a favorable anabolic-androgenic ratio. 

Nortestosterone. The reduced form, 3jS-hydroxy derivative (N-34) shows decreased androgenic and anabolic potencies with a favorable anabolic-androgenic ratio. The same applies for N-107. The N-26 and N-27 derivatives show a very favorable anabolic-androgenic ratio. 

On the contrary, 3 -hydroxy A (A-54) and 3j8-hydroxy A I7a-methyl (A-146) substitutions substantially increase the androgenic potency, while the former also increases to a smaller degree the anabolic potency, thus creating an unfavorable anabolic-androgenic ratio. The effect of 3/3-hydroxy A I7a-methyl substitution (A-146) on the anabolic activity is not known. 3/3-Acetoxy A 17-acetate (A-56) substitution has no effect on the androgenic activity while decreasing the anabolic activity of A-4. 

Androst-3,5-dien-17 -ol. 3-Methyl 17 -methyl (A-32), 3-chloro 17-acetate (A-155), 3-cyclohexylenol ether 17a-methyl (A-160), 3-cyclo-pentyl- (A-161) and 3-cyclopentylenol ether 17a-methyl (A-162) substitutions all significantly increase the androgenic activity. The anabolic activity is increased to a smaller degree to produce an unfavorable anabolic-androgenic ratio. 

Androst-5-en-l7 -ol. 3/3-Acetoxy 17a-propargyl(A-165), 3/3-hydroxy (A-152), 3/8-hydroxy 17a-methyl (A-5),and 3)3-hydroxy 17-ketone (A-57) substitutions all bring about a large decrease in androgenic and anabolic potencies, while the anabolic-androgenic ratio remains unfavorable. 

Testosterone. 7a-Methyl (S-21), 7o -methylthio 17-acetate (S-119), 7o -mercapto 17-acetate (S-121), and la,7a-dimethyl 17-acetate (S-80) compared to la-methyl 17-acetate (S-72) 7a-methyl 17-ketone (S-23) compared to I7-ketone (S-22) 7a-methyl A 17a-methyl (S-138), 7a-mercapto A 17a-methyl (S-57), and 7a-acetylthio A 17a-methyl (S-58) compared to A 17a-methyl (S-15) and 7a-methyl 17a-methyl (S-20) substitutions all increase both potencies, giving rise very often to a favorable anabolic-androgenic ratio. 7a-Acetylthio 17-acetate (S-120), 7a-mercapto 17a-methyl (S-53), 7a-methylthio 17a-methyl (S-54), 7a-ethyl-thio 17a-methyl (S-55), and 7a-acetylthio 17a-methyl (S-56) substitutions cause decrease of both androgenic and anabolic potencies while maintaining a favorable anabolic-androgenic ratio. 

Testosterone. A 9a-Bromo 11/3-chloro (S-123), 9a-chloro 11/3-fluoro (S-125), 9o -bromo 11/3-fiuoro 17-propionate (S-124), A" 9o -chloro 11/3-chloro 17a-methyl (S-127), 9a-bromo 11/3-fluoro 17a-methyl (S-128), 9a-bromo 1 l/S-fluoro 17a-methyl (S-126), 3-methylene 9o -fluoro 11/3-hydroxy 17a-methyl (S-28), 9a-fluoro 1 IjS-hydroxy 16a-methyl Ha-methyl (S-132), and A " 16a-methyl 17a-methyl (S-131) substitutions all lead to decreased androgenic potencies and, with the exception of S-127, to decreased anabolic potencies. The anabolic-androgenic ratio is often favorable. The androgenic potency of the 9a-fluoro 11/3-hydroxy 17-... 

A -Nortestosterone (N-95), 17a-methyl-A -nortestosterone (N-96) subcutaneously, and 17a-ethyl-A -nortestosterone (N-97) all exhibit greatly decreased androgenic activities while the anabolic activities are increased. I7a-Methyl-A -nortestosterone (N-96) orally shows increased androgenic and anabolic activities. The anabolic-androgenic ratio is very favorable in all cases. 

Stereochemically, while the hydrogens attached to C-2 and C-7 still constitute an axial and equatorial bond, the bond which attaches the hydrogen atom to C-8 is only approximately axial with respect to ring B. The nonbonded interaction exerted by C-9 and C-10 substituents is removed. These conformational changes have a favorable effect on the anabolic-androgenic ratio. 

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