R6890, sometimes known as spirochlorphine, is an opioid

analgesic An analgesic drug, also called simply an analgesic, antalgic, pain reliever, or painkiller, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in s ...

and a member of the spiropiperidine family of agents. The first known mention of this compound was in 1977. It has been advertised online as a

research chemical Research chemicals are chemical substances which scientists use for medical and scientific research purposes. One characteristic of a research chemical is that it is for laboratory research use only; a research chemical is not intended for human ...

having a potency 2-5 times that of fentanyl. Other examples of agents from this class are

Ro64-6198 Ro64-6198 is an opioid drug used in scientific research. It acts as a potent and selective agonist for the nociceptin receptor, also known as the ORL-1 (opiate receptor like-1) receptor, with over 100x selectivity over the other opioid receptors. ...

and

Ro65-6570 Ro65-6570 is an opioid drug. It has a potential use in preventing the addiction to other opioids. Mechanism of action Ro65-6570 is an opioid drug, it works by activating opioid receptors. However, instead of acting at the mu, kappa and delt ...

Brorphine Brorphine is a piperidine-based opioid analgesic compound. Brorphine was originally discovered in a 2018 paper investigating functionally biased opioid compounds, with the intention of finding safer analgesics that produce less respiratory depre ...

also has a similar structure. 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 Spirodecanone refers to a class of spirocyclic ketones, often studied for their potential applications in medicinal chemistry. One notable example is 1-Phenyl-1,3,8-triazaspiro .5ecan-4-one, which has been investigated as a metabolite of neurol ...

), which is used in the synthesis of other drugs including spirilene,

fluspirilene Fluspirilene (Redeptin, Imap, R6218) is a diphenylbutylpiperidine typical antipsychotic drug, used for the treatment of schizophrenia. It is administered intramuscularly. It was discovered at Janssen Pharmaceutica in 1963. A 2007 systematic revi ...

spiramide Spiramide (developmental code name AMI-193) is an experimental antipsychotic that acts as a selective 5-HT2A, 5-HT1A, and D2 receptor antagonist. It has negligible affinity for the 5-HT2C receptor. See also *Spirodecanone Spirodecanone ref ...

spiperone Spiperone, also known as spiroperidol and sold under the brand name Spiropitan (( JP)) is a typical antipsychotic of the butyrophenone family related to haloperidol. It is approved for clinical use in Japan as a treatment for schizophrenia. Pha ...

, RP-23618, spioxatrine, L008716 and R5260.

Pharmacology

The pharmacology of R6890 is described as a

nociceptin receptor The nociceptin opioid peptide receptor (NOP), also known as the nociceptin/orphanin FQ (N/OFQ) receptor or kappa-type 3 opioid receptor, is a protein that in humans is encoded by the ''OPRL1'' (opioid receptor-like 1) gene. The nociceptin recepto ...

(NOP) agonist, although R6890 retains significant affinity at the mu opioid receptor. R6890 has affinities (K_i values) of 4, 75, and 10 nM for the mu, delta, and the total

opioid receptor Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostati ...

population, respectively.

References

{{Opioid receptor modulators Analgesics Belgian inventions Euphoriants Mu-opioid receptor agonists Piperidines Synthetic opioids 4-Chlorophenyl compounds Anilines Spiro compounds Imidazolidinones