View source for Chemistry:16α-Hydroxyestrone

{{Chembox
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| ImageFile = 16α-Hydroxyestrone.svg
| ImageSize = 250
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<!-- Names -->
| IUPACName = 3,16α-Dihydroxyestra-1,3,5(10)-trien-17-one
| SystematicName = (2''R'',3a''S'',3b''R'',9b''S'',11a''S'')-2,7-Dihydroxy-11a-methyl-2,3,3a,3b,4,5,9b,10,11,11a-decahydro-1''H''-cyclopenta[''a'']phenanthren-1-one
| OtherNames = Hydroxyestrone; 16-Hydroxyestrone
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| Section1 = {{Chembox Identifiers
| CASNo = 566-76-7
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = JY611949JU
| ChemSpiderID = 103012
| ChEBI = 776
| InChI = 1S/C18H22O3/c1-18-7-6-13-12-5-3-11(19)8-10(12)2-4-14(13)15(18)9-16(20)17(18)21/h3,5,8,13-16,19-20H,2,4,6-7,9H2,1H3/t13-,14-,15+,16-,18+/m1/s1
| PubChem = 115116
| SMILES = C[C@]12CC[C@H]3[C@H]([C@@H]1C[C@H](C2=O)O)CCC4=C3C=CC(=C4)O
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| Section2 = {{Chembox Properties
| C=18 | H=22 | O=3
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'''16α-Hydroxyestrone''' ('''16α-OH-E1'''), or '''hydroxyestrone''', also known as '''estra-1,3,5(10)-triene-3,16α-diol-17-one''', is an endogenous [[Biology:Steroid|steroid]]al [[Biology:Estrogen|estrogen]] and a major [[Biology:Metabolite|metabolite]] of [[Chemistry:Estrone|estrone]], as well as an [[Biology:Metabolic intermediate|intermediate]] in the [[Biology:Biosynthesis|biosynthesis]] of [[Chemistry:Estriol|estriol]].<ref name="Rakel2012">{{cite book|first = David | last = Rakel | name-list-style = vanc |title=Integrative Medicine|url=https://books.google.com/books?id=jlVtJzBwAcEC&pg=PA338|year=2012|publisher=Elsevier Health Sciences|isbn=978-1-4377-1793-8|pages=338–339}}</ref><ref name="AcademicPress2005">{{cite book|title=Vitamins and Hormones|url=https://books.google.com/books?id=DUst5mwBfN0C&pg=PA282|date=7 September 2005|publisher=Academic Press|isbn=978-0-08-045978-3|pages=282–}}</ref> It is a potent estrogen similarly to estrone, and it has been suggested that the ratio of 16α-hydroxyestrone to 2-hydroxyestrone, the latter being much less estrogenic in comparison and even [[Chemistry:Antiestrogen|antiestrogen]]ic in the presence of more potent estrogens like [[Chemistry:Estradiol|estradiol]], may be involved in the [[Medicine:Pathophysiology|pathophysiology]] of [[Medicine:Breast cancer|breast cancer]].<ref name="Rakel2012" /> Conversely, 16α-hydroxyestrone may help to protect against [[Medicine:Osteoporosis|osteoporosis]].<ref name="Rakel2012" />

In terms of relative binding affinity (RBA) for the rat [[Biology:Uterus|uterine]] [[Biology:Estrogen receptor|estrogen receptor]], 16α-hydroxyestrone showed 2.8% of the affinity of [[Chemistry:Estradiol (medication)|estradiol]].<ref name="pmid7190977">{{cite journal | vauthors = Fishman J, Martucci C | title = Biological properties of 16 alpha-hydroxyestrone: implications in estrogen physiology and pathophysiology | journal = J. Clin. Endocrinol. Metab. | volume = 51 | issue = 3 | pages = 611–5 | date = September 1980 | pmid = 7190977 | doi = 10.1210/jcem-51-3-611 }}</ref> For comparison, [[Chemistry:Estrone (medication)|estrone]] had 11% of the affinity and [[Chemistry:Estriol (medication)|estriol]] had 10% of the affinity of estradiol.<ref name="pmid7190977" /> In contrast to other estrogens, the binding  of 16α-hydroxyestrone to the estrogen receptor is reported to be [[Chemistry:Covalent bond|covalent]] and [[Chemistry:Irreversible agonist|irreversible]].<ref name="OettelSchillinger2012">{{cite book | first1 = Michael | last1 = Oettel | first2 = Ekkehard | last2 = Schillinger | name-list-style = vanc |title=Estrogens and Antiestrogens I: Physiology and Mechanisms of Action of Estrogens and Antiestrogens|url=https://books.google.com/books?id=0BfrCAAAQBAJ&pg=PA252|date=6 December 2012|publisher=Springer Science & Business Media|isbn=978-3-642-58616-3|pages=252–}}</ref><ref name="pmid3186693">{{cite journal | vauthors = Swaneck GE, Fishman J | title = Covalent binding of the endogenous estrogen 16 alpha-hydroxyestrone to estradiol receptor in human breast cancer cells: characterization and intranuclear localization | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 85 | issue = 21 | pages = 7831–5 | date = November 1988 | pmid = 3186693 | pmc = 282290 | doi = 10.1073/pnas.85.21.7831 | bibcode = 1988PNAS...85.7831S | doi-access = free }}</ref><ref name="pmid9472688">{{cite journal | vauthors = Zhu BT, Conney AH | title = Functional role of estrogen metabolism in target cells: review and perspectives | journal = Carcinogenesis | volume = 19 | issue = 1 | pages = 1–27 | date = January 1998 | pmid = 9472688 | doi = 10.1093/carcin/19.1.1 | doi-access = free }}</ref><ref name="pmid16112947">{{cite journal | vauthors = Kuhl H | title = Pharmacology of estrogens and progestogens: influence of different routes of administration | journal = Climacteric | volume = 8 | pages = 3–63 | year = 2005 | issue = Suppl 1 | pmid = 16112947 | doi = 10.1080/13697130500148875 | s2cid = 24616324 | url = http://hormonebalance.org/images/documents/Kuhl%2005%20%20Pharm%20Estro%20Progest%20Climacteric_1313155660.pdf}}</ref> 16α-Hydroxyestrone has been reported to have 25% of the [[Biology:Vagina|vagina]]l [[Chemistry:Estrogen (medication)|estrogen]]ic [[Chemistry:Potency (pharmacology)|potency]] of estradiol.<ref name="pmid7190977">{{cite journal | vauthors = Fishman J, Martucci C | title = Biological properties of 16 alpha-hydroxyestrone: implications in estrogen physiology and pathophysiology | journal = J. Clin. Endocrinol. Metab. | volume = 51 | issue = 3 | pages = 611–5 | date = September 1980 | pmid = 7190977 | doi = 10.1210/jcem-51-3-611 }}</ref> The maximal uterotrophic and antigonadotropic effect of 16α-hydroxyestrone was equivalent to those of estradiol and estriol, indicating that 16α-hydroxyestrone is a fully effective estrogen.<ref name="pmid7190977" /><ref name="Velardo1964">{{cite book|last1=Velardo|first1=Joseph Thomas|title=Hormonal Steroids Biochemistry, Pharmacology, and Therapeutics|chapter=The Actions of Steroid Hormones on Estradiol-17β in Uterine Growth and Enzymorphology|year=1964|pages=463–490|doi=10.1016/B978-0-12-395506-7.50065-0|isbn=9780123955067}}</ref> However, 16α-hydroxyestrone was much less potent than estradiol or estrone.<ref name="Velardo1964" />

The C3 and C16α [[Chemistry:Acetate|diacetate]] [[Chemistry:Ester|ester]] of 16α-hydroxyestrone, [[Chemistry:Hydroxyestrone diacetate|hydroxyestrone diacetate]] (brand names Colpoginon, Colpormon, Hormobion, and Hormocervix), has been marketed and used medically as an estrogen in [[Earth:Europe|Europe]].<ref name="IndexNominum2000">{{cite book|title=Index Nominum 2000: International Drug Directory|url=https://books.google.com/books?id=5GpcTQD_L2oC&pg=PA1250|date=January 2000|publisher=Taylor & Francis|isbn=978-3-88763-075-1|pages=1250–}}</ref><ref name="Muller1998">{{cite book| first1 = Niels F | last1 = Muller | first2 = Rudolf P | last2 = Dessing | author3 = European Society of Clinical Pharmacy | name-list-style = vanc |title=European Drug Index: European Drug Registrations | edition = Fourth|url=https://books.google.com/books?id=2HBPHmclMWIC&pg=PA289|date=19 June 1998|publisher=CRC Press|isbn=978-3-7692-2114-5|pages=289–}}</ref>


==See also==
* [[Chemistry:2-Hydroxyestrone|2-Hydroxyestrone]]
* [[Chemistry:2-Hydroxyestradiol|2-Hydroxyestradiol]]
* [[Chemistry:16β-Hydroxyestrone|16β-Hydroxyestrone]]
* [[Chemistry:16-Ketoestrone|16-Ketoestrone]]
* 16α-Hydroxydehydroepiandrosterone
* [[Chemistry:16α-Hydroxyandrostenedione|16α-Hydroxyandrostenedione]]
* 15α-Hydroxydehydroepiandrosterone

==References==
{{Reflist}}


{{Endogenous steroids}}
{{Estrogen receptor modulators}}

{{DEFAULTSORT:Hydroxyestrone, 16α-}}

[[Category:Acyloins]]
[[Category:Estranes]]
[[Category:Estrogens]]
[[Category:Human metabolites]]
[[Category:Phenols]]



{{Sourceattribution|16α-Hydroxyestrone}}