levonorgestrel acetate levonorgestrel acetate levonorgestrel acetate (lng-a), or levonorgestrel 17β-acetate, also known as 3-ketonorgestimate, is a progestin which was never marketed. it is a progestogen ester and is the c17β acetate ester and a prodrug of levonorgestrel. norgestimate is the c3 oxime of lng-a. the drug is a minor active metabolite of norgestimate, which is a prodrug of norelgestromin and to a lesser extent of levonorgestrel and lng-a. lng-a has high affinity for the progesterone receptor, about 135% of that of promegestone (relative to 150% for levonorgestrel). along with levonorgestrel butanoate, lng-a was investigated as a hormonal contraceptive by the population council. levonorgestrel acetateclinical dataother nameslng-a; lnga; 3-ketonorgestimate; levonorgestrel 17β-acetate; d-(–)-norgestrel 17β-acetate; 17α-ethynyl-18-methylestr-4-en-17β-ol-3-one 17β-acetate; 17β-acetoxy-13β-ethyl-17α-ethynylgon-4-en-3-onedrug classprogestogen; progestogen esteridentifiers iupac name phenanthren-17-yl] acetate cas number13732-69-9 18290-31-8pubchem cid62954chemspider56666uniivf642934xzecha infocard100.123.252 chemical and physical dataformulac23h30o3molar mass354.490 g·mol−13d model (jsmol)interactive image smiles cc12cc3(1cc2(c#c)oc(=o)c)ccc4=cc(=o)cc34 inchi inchi=1s/c23h30o3/c1-4-22-12-10-19-18-9-7-17(25)14-16(18)6-8-20(19)21(22)11-13-23(22,5-2)26-15(3)24/h2,14,18-21h,4,6-13h2,1,3h3/t18-,19+,20+,21-,22-,23-/m0/s1key:ydqdjltyvzaoqx-gomytpfnsa-n