4804 T3D4749 Levonorgestrel A synthetic progestational hormone with actions similar to those of progesterone and about twice as potent as its racemic or (+-)-isomer (norgestrel). It is used for contraception, control of menstrual disorders, and treatment of endometriosis. It is usually supplied in a racemic mixture (Norgestrel, 6533-00-2). Only the levonorgestrel isomer is active. Levonorgestrel is marketed mostly as a combination oral contraceptive under several brand names such as Alesse, Triphasil, and Min-Ovral. 797-63-7 13109 C21H28O2 White powder. 240°C 2.05 mg/L Levonorgestrel is not subjected to a "first-pass" effect and is virtually 100% bioavailable. Binds to the progesterone and estrogen receptors. Target cells include the female reproductive tract, the mammary gland, the hypothalamus, and the pituitary. Once bound to the receptor, progestins like levonorgestrel will slow the frequency of release of gonadotropin releasing hormone (GnRH) from the hypothalamus and blunt the pre-ovulatory LH (luteinizing hormone) surge. Hepatic. Route of Elimination: About 45% of levonorgestrel and its metabolites are excreted in the urine and about 32% are excreted in feces, mostly as glucuronide conjugates. LD50 >5000 mg/kg (orally in rats) Norgestrel: Group 2B, possibly carcinogenic to humans. (L135) For the treatment of menopausal and postmenopausal disorders and alone or in combination with other hormones as an oral contraceptive. 2014-09-11T05:14:42Z 2026-03-26T20:09:04Z Levonorgestrel C08149 6443 DB00367 NOG true [H][C@@]12CC[C@@](O)(C#C)[C@@]1(CC)CC[C@]1([H])[C@@]3([H])CCC(=O)C=C3CC[C@@]21[H] C21H28O2 InChI=1S/C21H28O2/c1-3-20-11-9-17-16-8-6-15(22)13-14(16)5-7-18(17)19(20)10-12-21(20,23)4-2/h2,13,16-19,23H,3,5-12H2,1H3/t16-,17+,18+,19-,20-,21-/m0/s1 WWYNJERNGUHSAO-XUDSTZEESA-N 312.4458 312.20893014 Exogenous Solid 3.8 HMDB14511 CHEMBL1389 12560 <p>Yu-Sheng Chang, Shu-Ping Chen, &#8220;Levonorgestrel Crystallization.&#8221; U.S. Patent US20090069584, issued March 12, 2009.</p> CHEM003706 DTXSID3036496 NS00002177 (1S,2R,10R,11S,14R,15S)-15-ethyl-14-ethynyl-14-hydroxytetracyclo[8.7.0.0^{2,7}.0^{11,15}]heptadec-6-en-5-one