Thiafentanil

Not to be confused with Thiofentanyl.

Thiafentanil (A-3080, Thianil) is a highly potent opioid analgesic that is an analog of fentanyl, and was invented in 1986.^[1] Its analgesic potency is slightly less than that of carfentanil (itself approximately 10,000 times the potency of morphine, or 4,000 times that of heroin),^[2] though with a faster onset of effects, shorter duration of action and a slightly lesser tendency to produce respiratory depression. It is used in veterinary medicine to anesthetise animals such as impala, usually in combination with other anesthetics such as ketamine, xylazine or medetomidine to reduce the prevalence of side effects such as muscle rigidity.^[3]

Thiafentanil

Legal status
Legal status	CA: Schedule I UK: Class A US: Schedule II
Identifiers
IUPAC name methyl 4-(N-(2-methoxyacetyl)anilino)-1-(2-thiophen-2-ylethyl)piperidine-4-carboxylate
CAS Number	101345-60-2
PubChem CID	13653617
ChemSpider	58828132
UNII	HS2D307FGT
Chemical and physical data
Formula	C22H28N2O4S
Molar mass	416.54 g·mol−1
3D model (JSmol)	Interactive image
SMILES COCC(=O)N(C1=CC=CC=C1)C2(CCN(CC2)CCC3=CC=CS3)C(=O)OC
InChI InChI=1S/C22H28N2O4S/c1-27-17-20(25)24(18-7-4-3-5-8-18)22(21(26)28-2)11-14-23(15-12-22)13-10-19-9-6-16-29-19/h3-9,16H,10-15,17H2,1-2H3 Key:HFRKHTCPWUOGHM-UHFFFAOYSA-N

Side effects

Side effects of fentanyl analogs are similar to those of fentanyl itself, which include itching, nausea and potentially serious respiratory depression, which can be life-threatening. Potent pure opioid antagonists such as naltrexone or nalmefene are recommended in the event of accidental human exposure to thiafentanil.^[4] Fentanyl analogs have killed hundreds of people throughout Europe and the former Soviet republics since the most recent resurgence in use began in Estonia in the early 2000s, and novel derivatives continue to appear.^[5] A new wave of fentanyl analogues and associated deaths began in around 2014 in the US, and have continued to grow in prevalence; especially since 2016 these drugs have been responsible for hundreds of overdose deaths every week.^{[citation needed]}

Legal status

Thiafentanil is a Schedule II controlled drug in the USA since August 2016.^[6]

See also

• Sufentanil
• List of fentanyl analogues

References

1. US expired US4584303A, Bao-Shan Huang, Ross C. Terrell, Kirsten H. Deutsche, Linas V. Kudzma, Nhora L. Lalinde, "N-aryl-N-(4-piperidinyl)amides and pharmaceutical compositions and method employing such compounds", published 22 April 1986, issued 22 April 1986, assigned to Boc, Inc. and Anaquest, Inc.
2. Leen JL, Juurlink DN (April 2019). "Carfentanil: a narrative review of its pharmacology and public health concerns". Can J Anaesth. 66 (4): 414–421. doi:10.1007/s12630-019-01294-y. PMID 30666589. S2CID 58642995.
3. Zeiler GE, Meyer LC (September 2017). "Chemical capture of impala (Aepyceros melampus): A review of factors contributing to morbidity and mortality". Veterinary Anaesthesia and Analgesia. 44 (5): 991–1006. doi:10.1016/j.vaa.2017.04.005. PMID 29050999.
4. Haymerle A, Fahlman A, Walzer C. Human exposures to immobilising agents: results of an online survey. Vet Rec. 2010 Aug 28;167(9):327-32. Haymerle A, Fahlman A, Walzer C (August 2010). "Human exposures to immobilising agents: results of an online survey". The Veterinary Record. 167 (9): 327–32. doi:10.1136/vr.c4191. PMID 20802186. S2CID 207040439.
5. Mounteney J, Giraudon I, Denissov G, Griffiths P (July 2015). "Fentanyls: Are we missing the signs? Highly potent and on the rise in Europe". The International Journal on Drug Policy. 26 (7): 626–31. doi:10.1016/j.drugpo.2015.04.003. PMID 25976511.
6. Drug Enforcement Administration, Department of Justice (August 2016). "Schedules of Controlled Substances: Placement of Thiafentanil Into Schedule II. Interim final rule with request for comments". Federal Register. 81 (166): 58834–40. PMID 27568479.