4798 T3D4743 Ethinyl Estradiol A semisynthetic alkylated estradiol with a 17-alpha-ethinyl substitution. It has high estrogenic potency when administered orally and is often used as the estrogenic component in oral contraceptives . Ethinyl estradiol is marketed mostly as a combination oral contraceptive under several brand names such as Alesse, Tri-Cyclen, Triphasil, and Yasmin. The FDA label includes a black box warning that states that combination oral contraceptives should not be used in women over 35 years old who smoke due to the increased risk of serious cardiovascular side effects. 57-63-6 5991 C20H24O2 White powder. 142-144°C 11.3 mg/L (at 27°C) Rapid and complete absorption follows oral intake of ethinyl estradiol (bioavailability 43%). Estrogens diffuse into their target cells and interact with a protein receptor. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Estrogens increase the hepatic synthesis of sex hormone binding globulin (SHBG), thyroid-binding globulin (TBG), and other serum proteins and suppress follicle-stimulating hormone (FSH) from the anterior pituitary. This cascade is initiated by initially binding to the estrogen receptors. The combination of an estrogen with a progestin suppresses the hypothalamic-pituitary system, decreasing the secretion of gonadotropin-releasing hormone (GnRH). Hepatic. Quantitatively, the major metabolic pathway for ethinyl estradiol, both in rats and in humans, is aromatic hydroxylation, as it is for the natural estrogens. Half Life: 36 +/- 13 hours Oral, mouse LD<sub>50</sub>: 1737 mg/kg. No indication of carcinogenicity to humans (not listed by IARC). For treatment of moderate to severe vasomotor symptoms associated with the menopause, female hypogonadism, prostatic carcinoma-palliative therapy of advanced disease, breast cancer, as an oral contraceptive, and as emergency contraceptive. Symptoms of overdose include nausea and vomiting, and withdrawal bleeding may occur in females. The FDA label includes a black box warning that states that combination oral contraceptives with ethinyl estradiol should not be used in women over 35 years old who smoke due to the increased risk of serious cardiovascular side effects. 2014-09-11T05:14:23Z 2026-03-31T16:59:18Z Ethinylestradiol C07534 4903 ABIETADIENE DB00977 true [H][C@]12CC[C@](O)(C#C)[C@]1(C)CC[C@@]1([H])C3=CC=C(O)C=C3CC[C@]21[H] C20H24O2 InChI=1S/C20H24O2/c1-3-20(22)11-9-18-17-6-4-13-12-14(21)5-7-15(13)16(17)8-10-19(18,20)2/h1,5,7,12,16-18,21-22H,4,6,8-11H2,2H3/t16-,17-,18+,19+,20+/m0/s1 BFPYWIDHMRZLRN-CENDIDJXSA-N 296.41 296.177630013 Exogenous Solid 3.67 HMDB01926 CHEMBL691 5770 <p>Andreas Sachse, &#8220;Method of female hormonal contraception using a fixed extended cycle hormonal preparation containing dienogest and ethinyl estradiol.&#8221; U.S. Patent US20060079491, issued April 13, 2006.</p> CHEM003700 DTXSID5020576 (1R,10S,11R,14S,15R)-14-ethynyl-15-methyltetracyclo[8.7.0.0²,⁷.0¹¹,¹⁵]heptadeca-2,4,6-triene-5,14-diol