R6890

R6890, sometimes known as spirochlorphine, is an opioid analgesic and a member of the spiropiperidine family of agents.^[1][2][3] The first known mention of this compound was in 1977.^[4] It has been advertised online as a research chemical having a potency 2-5 times that of fentanyl.^{[citation needed]} Other examples of agents from this class are Ro64-6198 and Ro65-6570. Brorphine also has a similar structure.

Spirochlorphine

Clinical data
Other names	Spirochlorphine
Identifiers
IUPAC name 8-[1-(4-chlorophenyl)ethyl]-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-one
CAS Number	3222-88-6
PubChem CID	14783734
ChemSpider	21257352
ChEMBL	ChEMBL312281
Chemical and physical data
Formula	C21H24ClN3O
Molar mass	369.89 g·mol−1
3D model (JSmol)	Interactive image
SMILES CC(C1=CC=C(C=C1)Cl)N2CCC3(CC2)C(=O)NCN3C4=CC=CC=C4
InChI InChI=1S/C21H24ClN3O/c1-16(17-7-9-18(22)10-8-17)24-13-11-21(12-14-24)20(26)23-15-25(21)19-5-3-2-4-6-19/h2-10,16H,11-15H2,1H3,(H,23,26) Key:KFEYPBZJPJJRFX-UHFFFAOYSA-N

A precursor chemical used in the synthesis of R6890 is 1-phenyl-1,3,8-triazaspiro(4,5)decan-4-one (also known as spirodecanone), which is used in the synthesis of other drugs including spirilene, fluspirilene, spiramide, spiperone, RP-23618, spiroxatrine, L008716 and R5260.

Pharmacology

The pharmacology of R6890 is described as a nociceptin receptor (NOP) agonist, although R6890 retains significant affinity at the mu opioid receptor.^[5] R6890 has affinities (K_i values) of 4, 75, and 10 nM for the mu, delta, and the total opioid receptor population, respectively.^[6]

See also

• Cychlorphine
• List of orphine opioids