14-Methoxymetopon is an experimental
opioid
Opioids are a class of Drug, drugs that derive from, or mimic, natural substances found in the Papaver somniferum, opium poppy plant. Opioids work on opioid receptors in the brain and other organs to produce a variety of morphine-like effects, ...
drug developed by a team led by Professor Helmut Schmidhammer at the University of Innsbruck in the mid-1990s. It is a derivative of
metopon
Metopon (5-methylhydromorphone, CAS number 124-92-5) is an opioid analogue that is a methylated derivative of hydromorphone which was invented in 1929 as an analgesic
An analgesic drug, also called simply an analgesic, antalgic, pain reliev ...
in which a
methoxy
In organic chemistry, a methoxy group is the functional group consisting of a methyl group bound to oxygen. This alkoxy group has the formula .
On a benzene ring, the Hammett equation classifies a methoxy substituent at the ''para'' position a ...
group has been inserted at the 14-position. It is a highly potent
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 ...
drug that is around 500 times stronger than
morphine
Morphine, formerly also called morphia, is an opiate that is found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (''Papaver somniferum''). It is mainly used as an analgesic (pain medication). There are ...
when
administered systemically; however, when given spinally or supraspinally, it exhibits analgesic activity up to a million fold greater than morphine. It binds strongly to the
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 ...
and activates it to a greater extent than most similar opioid drugs. This produces an unusual pharmacological profile, and although 14-methoxymetopon acts as a potent μ-opioid full agonist in regard to some effects such as analgesia, a
ceiling effect is seen on other effects such as
constipation
Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The Human feces, stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the ...
and
respiratory depression
Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapni ...
which is believed to involve interaction with the
κ-opioid receptor
The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP for its ligand ketazocine, 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 re ...
.
See also
*
14-Methoxydihydromorphinone
References
4,5-Epoxymorphinans
Ethers
Hydroxyarenes
Ketones
Mu-opioid receptor agonists
Opioids
Semisynthetic opioids
{{Analgesic-stub