Norethandrolone is simply nandrolone with an added 17-alpha ethyl group. This alteration is rarely used with anabolic/androgenic steroids, and is much more commonly found with synthetic estrogens and progestins. Although 17-ethylation inhibits 17-ketosteroid reduction just as well as 17-methylation, and therefore allows this steroid to exhibit a similarly high level of oral activity, this group also tends to increase progesterone receptor binding. Norethandrolone is clearly a “troublesome” hormone in terms of water retention, fat gain, and gynecomastia, which may in part be due to its heightened binding to this receptor.
Ethylestrenol is an oral derivative of nandrolone, very similar in structure to keto group, which is vital to androgen receptor binding. As such, ethylestrenol is possibly the weakest steroid milligram for milligram ever sold commercially. Any activity this steroid does exhibit is likely from its conversion to norethandrolone, which does seem to occur with some affinity (apparently the 3 oxygen group is metabolically added to this compound without much trouble). This is probably the most interesting trait of ethylestrenol, which is an undistinguished compound otherwise.
Although a derivative of nandrolone, the two additional double-bonds present on trenbolone make any similarities to its parent hormone extremely difficult to see. First, the 9-10 bond inhibits aromatization. Nandrolone is very slowly aromatized, however, some estrogen is still produced from this steroid. Not so with trenbolone. The 11-12 bond additionally increases androgen receptor binding. This steroid also does not undergo 5-alpha reduction like nandrolone, and as such does not share the same dissociation between anabolic and androgenic effects (trenbolone is much more androgenic in comparison). Click here to see all and their prices.
Llewellyn, William. Anabolics