Quinestrol

Quinestrol (INN, USAN, BAN) (brand names Agalacto-Quilea, Basaquines, Eston, Estrovis, Estrovister, Plestrovis, Qui-lea), also known as ethinyl estradiol 3-cyclopentyl ether, is a synthetic, steroidal estrogen used in hormone replacement therapy and occasionally to treat breast cancer and prostate cancer.