Bucinnazine (AP-237, 1-butyryl-4-cinnamylpiperazine) is an

opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioi ...

analgesic drug that was widely used in China to treat

pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...

cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal bl ...

patients as of 1986. It is one of the most potent compounds among a series of piperazine-

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it is ...

s first synthesized and reported in Japan in the 1970s. Bucinnazine has analgesic potency comparable to that of

morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies ('' Papaver somniferum''). It is mainly used as a pain medication, and is also commonly used recreationally, or to make other illicit opioids. Ther ...

but with a relatively higher

therapeutic index The therapeutic index (TI; also referred to as therapeutic ratio) is a quantitative measurement of the relative safety of a drug. It is a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes ...

. The drug was initially claimed to be a non-narcotic analgesic. However, subsequent studies have shown bucinnazine and similar acyl piperazines to be potent and selective

agonists An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the agoni ...

μ-opioid receptor The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(''mu'')-opioid peptide (MOP) receptors. The prototypical ...

(MOR) with relatively low affinity for the

δ-opioid receptor The δ-opioid receptor, also known as delta opioid receptor or simply delta receptor, abbreviated DOR or DOP, is an inhibitory 7-transmembrane G-protein coupled receptor coupled to the G protein Gi/G0 and has enkephalins as its endogenous lig ...

and the

κ-opioid receptor The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP, is a G protein-coupled receptor that in humans is encoded by the ''OPRK1'' gene. The KOR is coupled to the G protein Gi/G0 and is one of four related receptors that bind o ...

. In accordance with these studies, results from the intravenous self-administration experiments in rats showed that bucinnazine has a marked reinforcing effect with

tolerance Tolerance or toleration is the state of tolerating, or putting up with, conditionally. Economics, business, and politics * Toleration Party, a historic political party active in Connecticut * Tolerant Systems, the former name of Veritas Software ...

and dependence quickly developing. In addition, the morphine antagonist naloxone reverses the effect of bucinnazine and precipitates withdrawal symptoms in bucinnazine treated rats further indicating a mechanism of analgesia mediated via selective agonist activity at μ-opioid receptors.

Derivatives

2-methyl-AP-237 has been sold on the grey market as a designer opioid, first identified by a police forensic laboratory in Slovenia in March 2019.

References

{{reflist Analgesics Euphoriants Mu-opioid receptor agonists Piperazines Amides

Derivatives

See also

References