W-18 (drug)

W-18 is a compound in a series of 32 substances (named W-1 to W-32) that were first synthesized in academic research on analgesic drug discovery in the 1980s and appeared as a designer drug in the 2010s.

W-18 (drug)

Legal status
Legal status	Illegal in Sweden and Canada
Identifiers
IUPAC name 4-chloro-N-[(2Z)-1-[2-(4-nitrophenyl)ethyl]piperidin-2-ylidene]benzene-1-sulfonamide
CAS Number	93101-02-1 N
PubChem CID	57501076
ChemSpider	28537256 Y
UNII	04WOYJF7QH
CompTox Dashboard (EPA)	DTXSID90726944
Chemical and physical data
Formula	C19H20ClN3O4S
Molar mass	421.90 g·mol−1
3D model (JSmol)	Interactive image
Melting point	157 to 158 °C (315 to 316 °F)
SMILES C1CCN(/C(=N\S(=O)(=O)C2=CC=C(C=C2)Cl)/C1)CCC3=CC=C(C=C3)[N+](=O)[O-]
InChI InChI=1S/C19H20ClN3O4S/c20-16-6-10-18(11-7-16)28(26,27)21-19-3-1-2-13-22(19)14-12-15-4-8-17(9-5-15)23(24)25/h4-11H,1-3,12-14H2/b21-19- Y Key:BKRSVROQVRTSND-VZCXRCSSSA-N Y
NY (what is this?)  (verify)

W-18 was invented at the University of Alberta by a lab working on analgesic drug discovery in the 1980s, and preliminary studies in animals showed it had pain-killing activity in mice.^[1][2]

The chemical was detected in connection with recreational drug use as substitute for other controlled substances in Europe in 2013,^[3] and in the United States.^[4] In Canada, Alberta Law Enforcement Response Teams (ALERT) seized four kilograms of W-18 in a drug bust in Edmonton in December 2015^[5] and W-18 was also detected by Health Canada in at least three of 110 fentanyl tablets seized from a Calgary home in August 2015.^[6][4]

W-18 was commonly reported to be an opioid in the popular press in the 2010s, which was later revealed not to be correct.^[7][8][9] W-18 was found to obtain weak activity at both sigma receptors and the translocator protein (peripheral benzodiazepine receptor).^[9] It also inhibits the hERG potassium channel with micromolar affinity, which could potentially cause cardiac arrhythmia at high doses.^[10]

• In Sweden, W-18 was made illegal in January 2016.^[11]
• In Canada, W-18 and its analogues were made Schedule I controlled substances.^[12] Possession without legal authority can result in maximum 7 years imprisonment. Further, Health Canada amended the Food and Drug Regulations in May, 2016 to classify W-18 as a restricted drug. Only those with a law enforcement agency, person with an exemption permit or institutions with Minister's authorization may possess the drug.

See also

• Ro5-4864