Plomestane

{{Short description|Chemical compound}}

{{Drugbox

| IUPAC_name = 10H-(2-Propynyl)-estr-4-ene-3,17-dione

| image = Plomestane.svg

| CAS_number = 77016-85-4

| CAS_supplemental =

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = FL3VS913TW

| ATC_prefix = None

| ATC_suffix =

| PubChem = 9904788

| ChemSpiderID = 8080442

| synonyms = MDL-18962; Propargylestrenedione; PED; 10-(2-Propyn-1-yl)estr-4-ene-3,17-dione; 10-Propargylestr-4-ene-3,17-dione

| C=21 | H=26 | O=2

| SMILES = O=C4\C=C3/[C@@](CC#C)([C@H]2CC[C@@]1(C(=O)CC[C@H]1[C@@H]2CC3)C)CC4

| StdInChI = 1S/C21H26O2/c1-3-10-21-12-8-15(22)13-14(21)4-5-16-17-6-7-19(23)20(17,2)11-9-18(16)21/h1,13,16-18H,4-12H2,2H3/t16-,17-,18-,20-,21-/m0/s1

| StdInChIKey = JKPDEYAOCSQBSZ-OEUJLIAZSA-N

| bioavailability =

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}}

Plomestane ({{abbrlink|INN|International Nonproprietary Name}}, {{abbrlink|USAN|United States Adopted Name}}; former developmental code name MDL-18962; also known as propargylestrenedione, PED) is a steroidal, irreversible aromatase inhibitor which was under development by Marion Merrell Dow/Hoechst Marion Russell (now Hoechst AG) as an antineoplastic agent for the treatment of breast cancer.{{cite book | vauthors = Macdonald F | title = Dictionary of Pharmacological Agents | url = https://books.google.com/books?id=A0THacd46ZsC&pg=PA1635 | access-date = 19 May 2012 | year = 1997 | publisher = CRC Press | isbn = 978-0-412-46630-4 | page = 1635}}{{cite book | vauthors = Morton IK, Hall JM | title = Concise Dictionary of Pharmacological Agents: Properties and Synonyms | url = https://books.google.com/books?id=mqaOMOtk61IC&pg=PA227 | access-date = 20 May 2012 | year = 1999 | publisher = Springer | isbn = 978-0-7514-0499-9 | page = 227}}{{cite journal | vauthors = Lombardi P | title = The irreversible inhibition of aromatase (oestrogen synthetase) by steroidal compounds | journal = Current Pharmaceutical Design | volume = 1 | pages = 23–50 (45) | url = https://books.google.com/books?id=qq8uPl5YYuoC&pg=PA45 | access-date = 20 May 2012 | date = June 1995 | publisher = Bentham Science Publishers | doi = 10.2174/1381612801666220524190226 | s2cid = 249298105 | url-access = subscription }}{{cite book | vauthors = Kreider RB, Leutholtz BC, Katch FI, Katch VL | title = Exercise and Sport Nutrition | url = https://books.google.com/books?id=PW1ja6KxakC&pg=PA350 | access-date = 20 May 2012 | year = 2009 | publisher = Exercise & Sport Nutrition | isbn = 978-0-9742965-6-2 | page = 350}}{{cite journal |vauthors=Kelloff GJ, Lubet RA, Lieberman R, etal | title = Aromatase inhibitors as potential cancer chemopreventives | journal = Cancer Epidemiology, Biomarkers & Prevention | volume = 7 | issue = 1 | pages = 65–78 |date=January 1998 | pmid = 9456245 | url = http://cebp.aacrjournals.org/cgi/pmidlookup?view=long&pmid=9456245}} It was found to be effective in preclinical studies and was also found to produce few adverse effects in human clinical trials, significantly reducing estrogen levels with a single administration. However, development of the drug for clinical use was halted due to "technical issues" and it was never marketed.{{cite book | vauthors = Avendaño C, Menéndez JC | title = Medicinal Chemistry of Anticancer Drugs | url = https://books.google.com/books?id=GjhXyqB5iLcC&pg=PA69 | access-date = 20 May 2012 | date = 4 June 2008 | publisher = Elsevier | isbn = 978-0-444-52824-7 | page = 69}}

In addition to its activity as an aromatase inhibitor, plomestane has weak androgenic properties.