sr-17018 sr-17018 sr-17018 is a drug which acts as a biased agonist at the μ-opioid receptor, selective for activation of the g-protein signalling pathway over β-arrestin 2 recruitment. in animal studies it produces analgesic effects but with less respiratory depression and development of tolerance than conventional opioids. sr-17018identifiers iupac name 5,6-dichloro-3-piperidin-4-yl]-1h-benzimidazol-2-one cas number2134602-45-0 ypubchem cid130431397chemspider67886365unii2m8p7uaw4wchemblchembl4452384pdb ligandwh9 (pdbe, rcsb pdb)chemical and physical dataformulac19h18cl3n3omolar mass410.72 g·mol−13d model (jsmol)interactive image smiles c1cn(ccc1n2c3=cc(=c(c=c3nc2=o)cl)cl)cc4=cc=c(c=c4)cl inchi inchi=1s/c19h18cl3n3o/c20-13-3-1-12(2-4-13)11-24-7-5-14(6-8-24)25-18-10-16(22)15(21)9-17(18)23-19(25)26/h1-4,9-10,14h,5-8,11h2,(h,23,26)key:lagudyugrsqdks-uhfffaoysa-n