Bucinnazine


Bucinnazine is an opioid analgesic drug that was widely used in China to treat pain in cancer patients as of 1986. It is one of the most potent compounds among a series of analgesic acyl piperazine compounds first synthesized and reported in Japan in the 1970s. Bucinnazine has analgesic potency comparable to that of morphine but with a relatively higher therapeutic index.
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 of μ-opioid receptor with relatively low affinity for the δ-opioid receptor and the κ-opioid receptor. In accordance with these studies, results from the intravenous self-administration experiments in rats showed that bucinnazine has a marked reinforcing effect with tolerance 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

The 2-methyl and 2,6-dimethyl derivatives of AP-237 are also known to be active as opioid analgesics, and 2-methyl-AP-237 has been sold as a designer drug, first identified by a police forensic laboratory in Slovenia in March 2019.
Image:2-Methyl-AP-237_structure.png|200px|thumb|left|2-Methyl-AP-237; CAS# 98608-59-4;