ATC code none PubChem CID 9046 Molar mass 364.52 g/mol | CAS Number 152-43-2 IUPHAR/BPS 7097 | |
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AHFS/Drugs.com Micromedex Detailed Consumer Information Synonyms W-3566;
3-Cyclopentyloxy-17-ethynyl-13-methyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-17-ol | ||
Quinestrol (INN, USAN, BAN) (brand names Agalacto-Quilea, Basaquines, Eston, Estrovis, Estrovister, Plestrovis, Qui-Lea), also known as ethinylestradiol 3-cyclopentyl ether (EE2CPE), is a synthetic, steroidal estrogen used in hormone replacement therapy and occasionally to treat breast cancer and prostate cancer. It is a prodrug of ethinylestradiol (with cyclopentanol also being formed) with no intrinsic estrogenic activity of its own, and has a very long terminal half-life of more than 120 hours due to enhanced lipophilicity. Because of its much longer terminal half-life, quinestrol is two to three times as potent as ethinylestradiol. The drug was marketed as Estrovis in the United States by Parke Davis and as Qui-Lea in Argentina, but is reportedly not currently marketed. However, it does appear to be available as an oral contraceptive in combination with progestins in Argentina and China. Quinestrol was described in the literature in 1967.