Levonorgestrel

• CAT Number: A000355
• CAS Number: 797-63-7
• Molecular Formula: C21H28O2
• Molecular Weight: 312.5
• Purity: ≥95%
• Synonyms: Norgestrel; 797-63-7; D-Norgestrel; Microval; Postinor
• Target: Estrogen/progestogen Receptor
• Solubility: >13.8mg/mL in DMSO
• Storage: -20°C
• 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
• InChIKey: WWYNJERNGUHSAO-XUDSTZEESA-N
• SMILES: CCC12CCC3C(C1CCC2(C#C)O)CCC4=CC(=O)CCC34

Levonorgestrel is a manufactured hormone used in a number of birth control methods. In pill form, it is useful within 120 hours as emergency birth control. It becomes less effective the longer after sex and only works before pregnancy has occurred. It is also combined with an estrogen to make combined oral birth control pill. Within an IUD, it is effective for long term prevention of pregnancy. An implantable form of levonorgestrel is also marketed in some countries.

Reference

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