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.
Dextromoramide is a powerful opioid analgesic approximately three times more potent than morphine but shorter acting. It is subject to drug prohibition regimes, both internationally through UN treaties and by the criminal law of individual states, and is usually prescribed only in the Netherlands.
Phenoperidine(Operidine or Lealgin), is an opioid analgesic which is structurally related to pethidine and is used clinically as a general anesthetic.
Lefetamine (Santenol) is a drug which is a stimulant and also an analgesic with effects comparable to codeine.
Bezitramide is an opioid analgesic. Bezitramide itself is a prodrug which is readily hydrolyzed in the gastrointestinal tract to its active metabolite, despropionyl-bezitramide. Bezitramide was discovered at Janssen Pharmaceutica in 1961. It is most commonly marketed under the trade name Burgodin.
Ohmefentanyl is an extremely potent opioid analgesic drug which selectively binds to the µ-opioid receptor.
3-Methylfentanyl is an opioid analgesic that is an analog of fentanyl. 3-Methylfentanyl is one of the most potent opioids, estimated to be between 400 and 6000 times stronger than morphine, depending on which isomer is used.
Allylprodine is an opioid analgesic that is an analog of prodine. It was discovered by Hoffman-La Roche in 1957 during research into the related drug pethidine. Derivatives were tested to prove the theory that phenolic & non-phenolic opioids bind at different sites of the opiate receptor.
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.
PEPAP (phenethylphenylacetoxypiperidine) is an opioid analgesic that is an analog of Desmethylprodine.
Viminol is an opioid analgesic developed by a team at the drug company Zambon in the 1960s. Viminol is based on the α-pyrryl-2-aminoethanol structure, unlike any other class of opioids.
IC-26 is an analogue of the opioid analgesic methadone, where the carbonyl group has been replaced by the bioisosteric sulfone group.
The Thiambutenes are a family of opioid analgesic drugs developed at the British research laboratory of Burroughs-Wellcome in the late 1940s. The parent compound thiambutene has no analgesic effects, but several compounds from this group are analgesics with around the same potency as morphine.
Azaprocin is a drug which is an opioid analgesic with approximately ten times the potency of morphine, and a fast onset and short duration of action. It was discovered in 1963, but has never been marketed.
SC-17599 is a steroid derivative drug discovered in 1968 which acts as a selective μ-opioid receptor agonist, with little or no affinity for the δ-opioid or κ-opioid receptors. It is an active analgesic in vivo, more potent than codeine or pethidine but slightly less potent than morphine, and produces similar effects to morphine in animals but with less sedation
BDPC is a potent narcotic analgesic with a distinctive arylcyclohexylamine chemical structure. It was developed by Daniel Lednicer at Upjohn in the 1970s. Initial studies estimated that it was around 10,000 times the strength of morphine in animal models. However, later studies using more modern techniques assigned a value of 504 times the potency of morphine for the more active trans-isomer. This drug was first seized along with three kilograms of acetylfentanyl in an April 25, 2013 police action in Montreal, Canada, and has reportedly continued to be available on the designer drug black market internationally. Analogues where the para-bromine is replaced by chlorine or a methyl group retain similar activity, as does the meta-hydroxyl derivative.
N-Methylnorcarfentanil (R-32395) is an opioid analgesic drug related to the highly potent animal tranquilizer carfentanil, but several thousand times weaker, being only slightly stronger than morphine. It was first synthesised by a team of chemists at Janssen Pharmaceutica led by Paul Janssen, who were investigating the structure-activity relationships of the fentanyl family of drugs. They found that replacing the phenethyl group attached to the piperidine nitrogen of fentanyl with a smaller methyl group, made it so much weaker that it was inactive as an analgesic in animals. However the same change made to the more potent analogue carfentanil retained reasonable opioid receptor activity, reflecting the higher binding affinity produced by the 4-carbomethoxy group.
Desmethylmoramide (INN) is an opioid analgesic related to dextromoramide that was synthesized and characterized in the late 1950s but was never marketed.
Diphenpipenol is an opioid analgesic drug invented in the 1970s by Dainippon Pharmaceutical Co. It is chemically a 1-substituted-4-(1,2-diphenylethyl)piperazine derivative related to compounds such as MT-45 and AD-1211, but diphenpipenol is the most potent compound in the series, with the more active (S) enantiomer being around 105 times the potency of morphine in animal studies. This makes it a similar strength to fentanyl and its analogues, and consequently diphenpipenol can be expected to pose a significant risk of producing life-threatening respiratory depression, as well as other typical opioid side effects such as sedation, itching, nausea and vomiting.
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