ic-26 ic-26 ic-26 (win 1161-3, methiodone) is an analogue of the opioid analgesic methadone, where the carbonyl group has been replaced by the bioisosteric sulfone group. ic-26identifiers iupac name 4-ethylsulfonyl-n,n-dimethyl-4,4-diphenylbutan-2-amine cas number114538-73-7 y 60662-79-5 (hydrochloride)pubchem cid113832chemspider102014uniizsy3t8j4aqchemical and physical dataformulac20h27no2smolar mass345.50 g·mol−13d model (jsmol)interactive image smiles ccs(=o)(=o)c(cc(c)n(c)c)(c1=cc=cc=c1)c2=cc=cc=c2 inchi inchi=1s/c20h27no2s/c1-5-24(22,23)20(16-17(2)21(3)4,18-12-8-6-9-13-18)19-14-10-7-11-15-19/h6-15,17h,5,16h2,1-4h3key:nlpgjspldndkkz-uhfffaoysa-n (verify) human and animal studies suggest that ic-26 is around the same potency as methadone, although other studies have found its activity to be inconsistent between different patients, with consistent opioid activity only being seen at a dose several times that of methadone. ic-26 was assessed for its abuse potential, but despite being found to have similar potential to methadone for development of dependence it was never placed under international control as an illegal drug.