Picenadol (LY-97435) is a 4- phenyl piperidine derivative that 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 opioid us ...

analgesic An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...

drug developed by Eli Lilly in the 1970s. Picenadol is an effective analgesic with similar efficacy to pethidine (meperidine). It has been investigated for some applications such as

obstetrics Obstetrics is the field of study concentrated on pregnancy, childbirth and the postpartum period. As a medical specialty, obstetrics is combined with gynecology under the discipline known as obstetrics and gynecology (OB/GYN), which is a surgi ...

and

dentistry Dentistry, also known as dental medicine and oral medicine, is the branch of medicine focused on the teeth, gums, and mouth. It consists of the study, diagnosis, prevention, management, and treatment of diseases, disorders, and conditions o ...

, but never commercialised. It is unusual in that one

enantiomer In chemistry, an enantiomer ( /ɪˈnænti.əmər, ɛ-, -oʊ-/ ''ih-NAN-tee-ə-mər''; from Ancient Greek ἐνάντιος ''(enántios)'' 'opposite', and μέρος ''(méros)'' 'part') – also called optical isomer, antipode, or optical ant ...

is a pure μ-opioid

agonist 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 ago ...

, while the other is an

antagonist An antagonist is a character in a story who is presented as the chief foe of the protagonist. Etymology The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...

. The (3R,4R) isomer is the agonist, while (3S,4S) is antagonist.Froimowitz M, Cody V. Absolute configurations and conformations of the opioid agonist and antagonist enantiomers of picenadol. ''Chirality''. 1995;7(7):518-25. This means that the racemic mix of the two enantiomers is a mixed agonist-antagonist, with relatively low

abuse potential Substance abuse, also known as drug abuse, is the use of a drug in amounts or by methods which are harmful to the individual or others. It is a form of substance-related disorder. Differing definitions of drug abuse are used in public health, ...

, and little of the κ-opioid activity that tends to cause problems with other opioid mixed agonist-antagonists such as

pentazocine Pentazocine, sold under the brand name Talwin among others, is a painkiller used to treat moderate to severe pain. It is believed to work by activating (agonizing) κ-opioid receptors (KOR) and μ-opioid receptors (MOR). As such it is called an ...

Synthesis

References

Synthetic opioids 4-Phenylpiperidines Phenols Mu-opioid receptor agonists {{analgesic-stub

Synthesis

See also

References