Morphinan analgesics

Racemorphane (— )-ALmethyl-3-methoxy-moiphinane antitussive (-f )-//-methyl-3-methoxy-morphinane analgesic Benson et alf ... 

Dibenz[h,e]azepine-6,11-diones ent-Morphinan nomenclature, 1, 29 Morphinan, 1,2,3,4-tetrahydro-nomenclature, 1, 29 14-a-Morphinan, N-methyl-synthesis, 1, 480 Morphinans nomenclature, 1, 29 as pharmaceuticals, 1, 148 synthesis, 2, 377 Morphine, 2, 512 as analgesic, 1, 167 as metabolite of normorphine, 1, 235 as pharmaceutical, 1, 146, 147, 148 synthesis, 1, 480 Morphine alkaloids structure, 4, 534 Morphin-7-en nomenclature, 1, 29 Morphinone, dihydro-as pharmaceutical, 1, 147 Morpholine — see also 1,4-Oxazine, tetrahydrocarcinogenicity, 1, 229 corrosion inhibitor, 1, 409 metabolism, 1, 226 nomenclature, 3, 996 structure, 2, 5 synthesis, 2, 89 Morpholine, 4-aciyloyl-polymers, 1, 291 Morpholine, alkenyl-polymers, 1, 291... 

In an extension of this work, Schnider and his colleagues condensed the salt (36) with the Grignard reagent from p-methoxy-benzyi chloride. The product (40), on reduction (41) and cycliza tion, affords the methoxylated morphinan (41). Removal of the methyl ether affords the narcotic analgesic racemorphan (43)... 

The search for opioid analgesics which show reduced addiction liability ha.s centered largely on benzomorphan and morphinan derivatives. Some research has, however, been devoted to derivatives of the structurally simpler meperidine series. The preparation of one such compound, picenadol (59), starts with the reaction of N-methyl-4-piperidone with the lithium derivative from m-methoxybromobenzene. Dehydration of the first formed carbinol 51 gives the intermediate 52. Deprotonation by means of butyl lithium gives an anion which can be depicted in the ambident form 53. In the event, treatment of the anion with propyl bromide gives the product 54 from reaction of the benzylic anion. Treatment of that product, which now contains an eneamine function. 

Little new work on analgesically active morphinan derivatives has appeared recently. Gates and Klein [56] have shown that a shift in the ethanamine bridge terminus of the morphinans from C-13 to C-14, giving metamorphinans (IX),... 

Papaverine (Figure 6.45) is a benzylisoquinoline alkaloid, and is structurally very different from the morphine, codeine, thebaine group of alkaloids (morphinans). It has little or no analgesic or hypnotic properties put possesses spasmolytic and vasodilator activity. It has been used in some expectorant preparations, and in the treatment of gastrointestinal spasms, but its efficacy was not substantiated. It is sometimes used as an effective treatment for male impotence, being administered by direct injection to achieve erection of the penis. 

Thebaine was isolated from opium in 1835 by Pelletier (439). The therapeutic applicability of thebaine was studied by Balint et al. (440). It was found to be more toxic than morphine. It is a more effective narcotic but a weaker analgesic than morphine. The analgesic effect of thebaine in doses of 0.01 g/kg is greater than that of amidopyrine this effect persists, however, only over a period of 30 min. Dihydro-thebaine is somewhat more effective but it is more toxic (441). The number and the location of the double bonds in ring D of the morphinane skeleton is of importance for the analgesic effect. Teraoko... 

A number of narcotic antagonists based on the morphinan stmcture have been marketed—for example, Buprenorphine, Naloxone, Naltrexone, and Nalorfine. Nalmefene is being pursued for the treatment of alcohol abuse. Oxycodone, and its precursor Codeine, are marketed, with restrictions, as analgesics. noSee Chapter 9, Table 3. 

Many opium-derived and other IQs are psychoactive, the best known being the analgesic, addictive, narcotic, opium-derived morphinan alkaloids codeine and morphine (heroin being the semi-synthetic diacetate of morphine). The tertiary or quaternary amine structural component is important for the activity of some Erytkrina alkaloids and bisbenzyliso-quinolines (notably the major curare component (+)-tubocurarine) as antagonists of the nACh-R involved in neuronal excitation of skeletal muscle. The planar disposition of some polycyclic benzophenanthridines enables intercalation (parallel interleaving) between the base pairs of DNA. A variety of naturally occurring and synthetic IQ compounds are protein kinase inhibitors. 

Morphinans (compactly fused Phe, C6, C5N, C6 and C40 rings) Codeine (opium-derived addictive, analgesic, antitussive, spasmolytic narcotic) morphine (opium-derived addictive, analgesic, antitussive, sedative, spasmolytic narcotic heroin is the semisynthetic diacetate) thebaine (non-analgesic, toxic, convulsant narcotic and semi-synthesis precursor of the anti-addiction drug naltrexone). 

Dihydrocodeine (=Paracodin)] (morphinan isoquinoline) Semi-synthetic from Codeine O-R agonist [analgesic, antitussive, narcotic] Hermann Goring, euphoric WW2 Luftwaffe C-in-C, on Dihydrocodeine (1937-1945)... 

Etorphine] (morphinan isoquinoline) Semi-synthetic trom Morphine O-R agonist - x [ 1 nM], 8 [ 1 nM], k [ 1 nM] [analgesic, antinociceptive]... 

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