Bentley compounds

Last updated
General structure of a Bentley compound with an ethano-bridge (single bond) Bentley compounds single bond.svg
General structure of a Bentley compound with an ethano-bridge (single bond)
General structure of a Bentley compound with an etheno-bridge (double bond) Bentley compounds double bond.svg
General structure of a Bentley compound with an etheno-bridge (double bond)

The Bentley compounds are a class of semi-synthetic opioids that were first synthesized by K. W. Bentley by Diels-Alder reaction of thebaine with various dienophiles. The compounds are also known as thevinols, orvinols, or bridged oripavine derivatives, due to the characteristic 6,14-endo-ethano- or etheno-bridge and substitution at the 7α position. Buprenorphine and etorphine are perhaps the best known of the family, which was the first series of extremely potent μ-opioid agonists, with some compounds in the series having over many thousands of times the analgesic potency of morphine. [1] [2] [3] [4] [5]

See also

Related Research Articles

<span class="mw-page-title-main">Morphine</span> Pain medication of the opiate family

Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies. It is mainly used as a pain medication, and is also commonly used recreationally, or to make other illicit opioids. There are numerous methods used to administer morphine: oral; sublingual; via inhalation; injection into a muscle; by injection under the skin; intravenously; injection into the space around the spinal cord; transdermal; or via rectal suppository. It acts directly on the central nervous system (CNS) to induce analgesia and alter perception and emotional response to pain. Physical and psychological dependence and tolerance may develop with repeated administration. It can be taken for both acute pain and chronic pain and is frequently used for pain from myocardial infarction, kidney stones, and during labor. Its maximum effect is reached after about 20 minutes when administered intravenously and 60 minutes when administered by mouth, while the duration of its effect is 3–7 hours. Long-acting formulations of morphine are available as MS-Contin, Kadian, and other brand names as well as generically.

<span class="mw-page-title-main">Thebaine</span> Chemical compound

Thebaine (paramorphine), also known as codeine methyl enol ether, is an opiate alkaloid, its name coming from the Greek Θῆβαι, Thēbai (Thebes), an ancient city in Upper Egypt. A minor constituent of opium, thebaine is chemically similar to both morphine and codeine, but has stimulatory rather than depressant effects. At high doses, it causes convulsions similar to strychnine poisoning. The synthetic enantiomer (+)-thebaine does show analgesic effects apparently mediated through opioid receptors, unlike the inactive natural enantiomer (−)-thebaine. While thebaine is not used therapeutically, it is the main alkaloid extracted from Papaver bracteatum and can be converted industrially into a variety of compounds, including hydrocodone, hydromorphone, oxycodone, oxymorphone, nalbuphine, naloxone, naltrexone, buprenorphine, butorphanol and etorphine.

<span class="mw-page-title-main">Opioid</span> Psychoactive chemical

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 use disorder, reversing opioid overdose, and suppressing cough. Extremely potent opioids such as carfentanil are approved only for veterinary use. Opioids are also frequently used non-medically for their euphoric effects or to prevent withdrawal. Opioids can cause death and have been used for executions in the United States.

<span class="mw-page-title-main">Desmethylprodine</span> Chemical compound

Desmethylprodine or 1-methyl-4-phenyl-4-propionoxypiperidine is an opioid analgesic drug developed in the 1940s by researchers at Hoffmann-La Roche. Desmethylprodine has been labeled by the DEA as a Schedule I drug in the United States. It is an analog of pethidine (meperidine) a Schedule II drug. Chemically, it is a reversed ester of pethidine which has about 70% of the potency of morphine. Unlike its derivative prodine, it was not reported to exhibit optical isomerism. It was reported to have 30 times the activity of pethidine and a greater analgesic effect than morphine in rats, and it was demonstrated to cause central nervous system stimulation in mice.

<span class="mw-page-title-main">Oxymorphone</span> Chemical compound

Oxymorphone is a highly potent opioid analgesic indicated for treatment of severe pain. Pain relief after injection begins after about 5–10 minutes, after oral administration it begins after about 30 minutes, and lasts about 3–4 hours for immediate-release tablets and 12 hours for extended-release tablets. The elimination half-life of oxymorphone is much faster intravenously, and as such, the drug is most commonly used orally. Like oxycodone, which metabolizes to oxymorphone, oxymorphone has a high potential to be abused.

<span class="mw-page-title-main">Etorphine</span> Semi-synthetic opioid

Etorphine (M99) is a semi-synthetic opioid possessing an analgesic potency approximately 1,000–3,000 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather the related plants Papaver orientale and Papaver bracteatum. It was later reproduced in 1963 by a research group at MacFarlan Smith in Gorgie, Edinburgh, led by Kenneth Bentley. It can also be produced from thebaine.

<span class="mw-page-title-main">Morphinan</span> Chemical compound

Morphinan is the prototype chemical structure of a large chemical class of psychoactive drugs, consisting of opiate analgesics, cough suppressants, and dissociative hallucinogens, among others.

<span class="mw-page-title-main">Dihydroetorphine</span> Chemical compound

Dihydroetorphine was developed by K. W. Bentley at McFarlan-Smith in the 1960s and is a potent opioid analgesic used mainly in China. It is a derivative of the better-known opioid etorphine, a very potent veterinary painkiller and anesthetic medication used primarily for the sedation of large animals such as elephants, giraffes, and rhinos.

<span class="mw-page-title-main">Oripavine</span> Chemical compound

Oripavine is an opioid and the major metabolite of thebaine. It is the parent compound from which a series of semi-synthetic opioids are derived, which includes the compounds etorphine and buprenorphine. Although its analgesic potency is comparable to morphine, it is not used clinically due to its severe toxicity and low therapeutic index. Due to its use in manufacture of strong opioids, oripavine is a controlled substance in some jurisdictions.

<span class="mw-page-title-main">Acetorphine</span> Chemical compound

Acetorphine is a potent opioid analgesic, up to 8700 times stronger than morphine by weight. It is a derivative of the more well-known opioid etorphine, which is used as a very potent veterinary painkiller and anesthetic medication, primarily for the sedation of large animals such as elephants, giraffes and rhinos.

<span class="mw-page-title-main">Cyprenorphine</span> Chemical compound

Cyprenorphine (M285), N-cyclo-propylmethyl-6,14-endoetheno-7α-(1-hydroxy-1-methylethyl)-6,7,8,14-tetrahydronororipavine, is an opioid drug. It is related to more well-known opioids such as buprenorphine, which is used as an analgesic and for the treatment of opioid addiction, and diprenorphine, which is used as an antidote to reverse the effects of other opioids. It is roughly 35 times as strong as nalorphine.

<span class="mw-page-title-main">Heterocodeine</span> Chemical compound

Heterocodeine (6-methoxymorphine) is an opiate derivative, the 6-methyl ether of morphine, and a structural isomer of codeine; it is called "hetero-" because it is the reverse isomer of codeine. Heterocodeine was first synthesised in 1932 and first patented in 1935. It can be made from morphine by selective methylation. Codeine is the natural mono-methyl ether, but must be metabolized for activity. In contrast the semi-synthetic mono-methyl ether, heterocodeine is a direct agonist. The 6,7,8,14 tetradehydro 3,6 methyl di-ether of morphine is thebaine.

<span class="mw-page-title-main">7-PET</span> Chemical compound

7-PET is an opioid analgesic drug that has 300 times the potency of morphine by weight. It was discovered by K.W. Bentley and is related to the more well known oripavine derivative etorphine, which is used as a veterinary painkiller and anesthetic medication for the sedation of large animals such as elephants, giraffes, and rhinos. 7-PET itself has a 3-O-methyl ether which reduces potency, but the 3-OH derivative is around 2200 times more potent than morphine, almost the same potency as etorphine as a μ agonist, and unexpectedly the 3-hydrogen compound is also around the same potency of 2000 times morphine.

<i>Papaver bracteatum</i> Species of flowering plant

Papaver bracteatum, also known as the Iranian poppy or Persian poppy and the great scarlet poppy is a sturdy hardy perennial poppy with large deep red flowers up to 8 inches (20 cm) in diameter on stiff stalks up to 4 feet high with a prominent black spot near the base of the petals. It is closely related to the commonly cultivated oriental poppy, Papaver orientale and is sometimes recorded as the varietal form Papaver orientale var. bracteatum.

<span class="mw-page-title-main">Opiate</span> Substance derived from opium

An opiate, in classical pharmacology, is a substance derived from opium. In more modern usage, the term opioid is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain. Opiates are alkaloid compounds naturally found in the opium poppy plant Papaver somniferum. The psychoactive compounds found in the opium plant include morphine, codeine, and thebaine. Opiates have long been used for a variety of medical conditions with evidence of opiate trade and use for pain relief as early as the eighth century AD. Opiates are considered drugs with moderate to high abuse potential and are listed on various "Substance-Control Schedules" under the Uniform Controlled Substances Act of the United States of America.

<i>N</i>-Phenethylnormorphine Chemical compound

N-Phenethylnormorphine is an opioid analgesic drug derived from morphine by replacing the N-methyl group with β-phenethyl. It is around eight to fourteen times more potent than morphine as a result of this modification, in contrast to most other N-substituted derivatives of morphine, which are substantially less active, or act as antagonists. Binding studies have helped to explain the increased potency of N-phenethylnormorphine, showing that the phenethyl group extends out to reach an additional binding point deeper inside the μ-opioid receptor cleft, analogous to the binding of the phenethyl group on fentanyl.

<span class="mw-page-title-main">Conolidine</span> Chemical compound

Conolidine is an indole alkaloid. Preliminary reports suggest that it could provide analgesic effects with few of the detrimental side-effects associated with opioids such as morphine, though at present it has only been evaluated in mouse models.

<span class="mw-page-title-main">Total synthesis of morphine and related alkaloids</span>

Synthesis of morphine-like alkaloids in chemistry describes the total synthesis of the natural morphinan class of alkaloids that includes codeine, morphine, oripavine, and thebaine and the closely related semisynthetic analogs methorphan, buprenorphine, hydromorphone, hydrocodone, isocodeine, naltrexone, nalbuphine, oxymorphone, oxycodone, and naloxone.

<span class="mw-page-title-main">6,14-Endoethenotetrahydrooripavine</span> Chemical compound

6,14-Endoethenotetrahydrooripavine is the central nucleus, or backbone, of a class of morphinan opioids known as the Bentley compounds and may be considered their "privileged scaffold". These include but are not limited to etorphine and buprenorphine. They usually have thebaine or oripavine as their precursor in their syntheses.

References

  1. Bentley, K. W.; Boura, A. L.; Fitzgerald, A. E.; Hardy, D. G.; McCoubrey, A.; Aikman, M. L.; Lister, R. E. (1965). "Compounds Possessing Morphine-Antagonising or Powerful Analgesic Properties". Nature. 206 (4979): 102–103. Bibcode:1965Natur.206..102B. doi:10.1038/206102a0. PMID   14334338. S2CID   4296776.
  2. Bentley, K. W.; Hardy, D. G. (1967). "Novel Analgesics and Molecular Rearrangements in the Morphine-Thebaine group. I. Ketones Derived from 6,14-endo-Ethenotetrahydrothebaine". Journal of the American Chemical Society. 89 (13): 3267–3273. doi:10.1021/ja00989a030.
  3. Bentley, K. W.; Hardy, D. G.; Meek, B. (1967). "Novel Analgesics and Molecular Rearrangements in the Morphine-Thebaine Group. II. Alcohols Derived from 6,14-endo-Etheno- and 6,14-endo-Ethanotetrahydrothebaine". Journal of the American Chemical Society. 89 (13): 3273–3280. doi:10.1021/ja00989a031. PMID   6042763.
  4. Bentley, K. W.; Hardy, D. G. (1967). "Novel Analgesics and Molecular Rearrangements in the Morphine-Thebaine Group. III. Alcohols of the 6,14-endo-ethenotetrahydrooripavine Series and Derived Analogs of N-Allylnormorphine and -norcodeine". Journal of the American Chemical Society. 89 (13): 3281–3292. doi:10.1021/ja00989a032. PMID   6042764.
  5. Bentley, K. W.; Hardy, D. G.; Meek, B. (1967). "Novel Analgesics and Molecular Rearrangements in the Morphine-Thebaine Group. IV. Acid-Catalyzed Rearrangements of Alcohols of the 6,14-endo-Ethenotetrahydrothebaine Series". Journal of the American Chemical Society. 89 (13): 3293–3303. doi:10.1021/ja00989a033. PMID   6042765.