acetylmethadol acetylmethadol acetylmethadol, also known as methadyl acetate, is a synthetic opioid analgesic. it is a racemic mixture of alphacetylmethadol (α-acetylmethadol) and betacetylmethadol (β-acetylmethadol), which are in turn racemic mixtures of levacetylmethadol (laam; l-α-acetylmethadol) and d-α-acetylmethadol and l-β-acetylmethadol and d-β-acetylmethadol, respectively. hence, acetylmethadol has four possible optical isomers. all of these isomers have been shown to partially or fully substitute for the discriminative stimulus effects of heroin in rats, and thus it can be inferred that, in addition to laam which is used clinically as such, they are all likely to be active opioid analgesics in humans. not to be confused with alphacetylmethadol (α-acetylmethadol) or levacetylmethadol (l-α-acetylmethadol). acetylmethadolclinical dataother namesmethadyl acetate (usan us)atc codenonelegal statuslegal status au: s8 (controlled drug) ca: schedule i de: anlage i (authorized scientific use only) us: schedule i identifiers iupac name (±)-6-(dimethylamino)-4,4-diphenyl-3-heptanyl acetate cas number509-74-0 ypubchem cid10517drugbankdb01433chemspider10080uniil59oc40kwjcomptox dashboard (epa)dtxsid2023274 echa infocard100.007.368 chemical and physical dataformulac23h31no2molar mass353.506 g·mol−13d model (jsmol)interactive image smiles o=c(oc(c(c1ccccc1)(c2ccccc2)cc(n(c)c)c)cc)c inchi inchi=1s/c23h31no2/c1-6-22(26-19(3)25)23(17-18(2)24(4)5,20-13-9-7-10-14-20)21-15-11-8-12-16-21/h7-16,18,22h,6,17h2,1-5h3key:xbmivrrwgcybtq-uhfffaoysa-n in the united states, acetylmethadol and its individual isomers are all schedule i drugs under the controlled substances act, except laam, which is schedule ii and was used clinically until 2003. acetylmethadol has an acscn of 9601. the isomers have individual acscns, which are as follows: alphacetylmethadol 9603, betacetylmethadol 9607, laam 9648. all of the above have annual manufacturing quotas of 2 grams as of 2013, except laam, which is 4 grams.