Open Access Articles- Top Results for 19-Norandrostenedione


Systematic (IUPAC) name
Clinical data
734-32-7 7pxN
PubChem CID 92834
DrugBank DB01434 7pxY
ChemSpider 83803 7pxY
Chemical data
Formula C18H24O2
272.38 g/mol
 14pxN (what is this?)  (verify)

19-Norandrostenedione (4-estrene-3,17-dione, NOR) is a precursor of the anabolic steroid nandrolone. Until 2005 19-Norandrostenedione was available without prescription in United States, where it was marketed as a prohormone, but it is now classified as a Schedule III drug. It is also banned from use in many sports, including the Olympic Games, under the World Anti-Doping Code.[1] 19-Norandrostenedione is readily metabolized to nandrolone after oral administration, but its potency to transactivate the androgen receptor dependent reporter gene expression is 10 times lower as compared to dihydrotestosterone (DHT).[2]

Scientific studies have shown that oral administration of 19-norandrostenedione is "a very ineffective strategy for stimulating skeletal muscle mass increases but may be associated with side effects".[3]

In vivo experiments in castrated rats demonstrated that subcutaneous treatment with 19-norandrostenedione resulted only in a stimulation of the weight of the levator ani muscle, while the prostate and seminal vesicle weights remained completely unaffected. In contrast to its metabolite nandrolone, 19-norandrostenedione highly selectively stimulates the growth of the skeletal muscles but has only weak androgenic properties.[2]

In the early 2000s, contamination of androstenedione products with traces of 19-norandrostenedione caused false positives for doping tests for nandrolone because 19-norandrosterone is a metabolite of both nandrolone and 19-norandrostenedione. In a randomized controlled trial trace contamination of androstenedione with 19-norandrostenedione was sufficient for users of androstendione to test positive for nandrolone.[4] This detail became less relevant after 19-norandrostenedione and androstenedione were banned by major sporting bodies.

See also


  1. "The World Anti-Doping Code: The 2012 Prohibited List" (PDF). World Anti-Doping Agency. Retrieved 2012-07-16. 
  2. 2.0 2.1 Diel P, Friedel A, Geyer H, Kamber M, Laudenbach-Leschowsky U, Schänzer W, Schleipen B, Thevis M, Vollmer G, Zierau O (April 2008). "The prohormone 19-norandrostenedione displays selective androgen receptor modulator (SARM) like properties after subcutaneous administration". Toxicol. Lett. 177 (3): 198–204. PMID 18325697. doi:10.1016/j.toxlet.2008.01.014. 
  3. Parr, MK; Laudenbach-Leschowsky, U; Höfer, N; Schänzer, W; Diel, P (2009). "Anabolic and androgenic activity of 19-norandrostenedione after oral and subcutaneous administration--analysis of side effects and metabolism". Toxicology letters 188 (2): 137–41. PMID 19446246. doi:10.1016/j.toxlet.2009.03.024. 
  4. Catlin DH, Leder BZ, Ahrens B, Starcevic B, Hatton CK, Green GA, Finkelstein JS (2000). "Trace contamination of over-the-counter androstenedione and positive urine test results for a nandrolone metabolite". JAMA 284 (20): 2618–21. PMID 11086369. doi:10.1001/jama.284.20.2618.