View source for Norsteroid

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'''''Norsteroid'''s'' ([[nor-]], L. ''norma'', from "normal" in chemistry, indicating carbon removal) are a structural class of steroids that have had an atom or atoms (typically carbon) removed, [[biosynthesis|biosynthetically]] or [[chemical synthesis|synthetically]], from positions of branching off of rings or side chains (e.g., removal of [[methyl]] groups), or from within rings of the steroid ring system.<ref>International Union of Pure and Applied Chemistry (IUPAC), 1999, "RF-4.1 Removal of Skeletal Atoms," in "RF-4. Skeletal Modifications" in Revised Section F: Natural Products and Related Compounds (IUPAC Recommendations 1999), see [http://www.chem.qmul.ac.uk/iupac/sectionF/RF41.html#41] {{Webarchive|url=https://web.archive.org/web/20160304041709/http://www.chem.qmul.ac.uk/iupac/sectionF/RF41.html#41 |date=2016-03-04 }}, accessed 20 May 2014.  See also IUPAC, 1976, "Nomenclature of Organic Chemistry: Section F - Natural Products and Related Compounds, Recommendations 1976", IUPAC Information Bulletin Appendices on Tentative Nomenclature, Symbols, Units, and Standards, No. 53, December, 1976, also in ''Eur. J. Biochem.'' 1978, '''86''', 1-8.</ref><ref>{{MeshName|Norsteroids}}</ref> For instance, 19-norsteroids (e.g., [[19-norprogesterone]]) constitute an important class of natural and synthetic steroids derived by removal of the methyl group of the [[natural product]] [[progesterone]]; the equivalent change between [[testosterone]] and [[nandrolone|19-nortestosterone]] (nandrolone) is illustrated below.

==Examples==
Norsteroid examples include: [[19-norpregnane]] (from  [[pregnane]]), [[desogestrel]], [[ethylestrenol]], [[etynodiol diacetate]], [[ethinylestradiol]], [[gestrinone]], [[levonorgestrel]], [[norethisterone]] (norethindrone), [[norgestrel]], norpregnatriene (from [[pregnatriene]]), [[quinestrol]], [[19-norprogesterone]] (from a [[progesterone]]), [[Nomegestrol acetate]],<ref name="pmid8954018">{{cite journal |vauthors=Couzinet B, Young J, Brailly S, Chanson P, Thomas JL, Schaison G |title=The antigonadotropic activity of progestins (19-nortestosterone and 19-norprogesterone derivatives) is not mediated through the androgen receptor |journal=J. Clin. Endocrinol. Metab. |volume=81 |issue=12 |pages=4218–23 |date=December 1996 |pmid=8954018 |doi= 10.1210/jcem.81.12.8954018 |url=http://jcem.endojournals.org/cgi/pmidlookup?view=long&pmid=8954018|doi-access=free }}</ref>{{primary source inline|date=May 2014}} [[nandrolone|19-nortestosterone]] (from a [[testosterone]]), and [[norethisterone acetate]].<ref name="pmid8954018"/>{{primary source inline|date=May 2014}}

{|
|- align="center"
| [[File:Progesterone.svg|140px]] || &nbsp;&nbsp; || [[File:19-Norprogesterone.svg|140px]]
|-
| [[progesterone]] || || [[19-Norprogesterone|19-norprogesterone]]
|-
| [[File:Testosteron.svg|140px]] || &nbsp;&nbsp; || [[File:Nandrolone.svg|140px]]
|-
| [[testosterone]] || || [[nandrolone]] (nortestosterone)
|}

==References==
{{Reflist}}

==External links==
* {{cite journal |vauthors=Bricout V, Wright F | title = Update on nandrolone and norsteroids: how endogenous or xenobiotic are these substances? | journal = Eur J Appl Physiol | volume = 92 | issue = 1–2 | pages = 1–12 | year = 2004 | pmid = 15042372 | doi = 10.1007/s00421-004-1051-3| s2cid = 6472015 }}

{{Steroid classification}}

[[Category:Steroids]]


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