Morphine from codeine

Codeine Minimal Safe in most cases. Neonatal toxicity described when the mother is an ultra rapid 2D6 metabolizer, producing substantially more morphine from codeine. 

TPMT) or the liver (for UGT and CYP2C9). Certain mutations in these isoforms, or gene variants, produce different phenotypes but most important to drug dosing is the poor metabolizer phenotype that results in heightened exposure to either the parent drug or a major metabolite, or reduced exposure to an active metabolite (e.g., morphine from codeine administration). 

In the discovery phase, metabolite identification is usually performed with a combination of in vitro and in vivo experiments using samples from different species in order to compare metabolite exposures. The structural identification of major circulating metabolites formed in nonclinical animal models as well as the metabolites formed in human in vitro systems is needed for the metabolites to be synthesized and their pharmacological activities and/or toxicological implications to be determined [25], In addition, metabolite identification can lead to the discovery of candidates with satisfactory clearance/PK properties and/or improved safety profile. Following are some examples of metabolites that were later developed as drugs desloratadine from loratadine, acetaminophen from phenacetin, morphine from codeine, minoxidil sulfate from minoxidil, fexofenadine from terfenadine, and oxazepam from diazepam. 

The processes used in the manufacture of morphine are believed to be still based on that described by the Scottish chemist Gregory,in 1833, with improvements devised by Anderson. A description has been published by Schwyzer, who also deals with the manufactme of codeine, narcotine, cotarnine, and the commercially important morphine derivatives, diamorphine (diacetylmorphine), and ethylmorphine (morphine ethyl ether). More recently Barbier has given an account of processes, based on long experience in the preparation of alkaloids from opium. Kanewskaja has described a process for morphine, narcotine, codeine, thebaine and papaverine, and the same bases are dealt with by Chemnitius, with the addition of narceine, by Busse and Busse, and by Dott. It is of interest to note that a number of processes for the extraction and separation of opium alkaloids have been protected by patent in Soviet Russia. ... 

Papaverine, C20H21O4N. This alkaloid, first obtained by Merck, occurs in the mixture precipitated by ammonia from the mother liquors of opium extract from which morphine and codeine have been separated in Gregory s process, and methods for its isolation from this mixture have been published by Hesse and others. The alkaloid may be purified by conversion into the acid oxalate, B. H2C2O4, m.p. 196° or 201-5-202°, which is nearly insoluble in alcohol. 

When Montgomery and I published our article, we thought we had disproven another theory of placebo effects - the theory that placebo effects are produced by the release of endorphins in the brain. In 1978 researchers at the University of California in San Francisco discovered that when placebos reduce pain, they may stimulate the release of endorphins.18 Endorphins, the existence of which had only been discovered a few years earlier, are opioids that are produced naturally by the brain. Just like the opiates that are derived from opium - morphine and codeine, for example - endorphins reduce the sensation of pain. The University of California researchers reasoned that if placebos can mimic the effects of opiate drugs, maybe they do so by stimulating the release of the brain s endogenous opioids. 

Opium The extract from Papaver somniferum containing morphine and codeine. 

Both morphine and codeine are valuable analgesics. Morphine is extracted from opium, the dried latex of the opium poppy, and codeine is usually obtained from morphine by semi-synthesis (see Box 6.2), since the amounts in opium are rather small. Thebaine is a valuable raw material for semi-synthesis of a wide range of morphine-like drugs. 

Codeine (12) and morphine (13), both major active constituents of opium resin, the dried latex from the immature fruits of Papaver som-niferum L., are pharmacologically important drugs as analgesic agents with considerable use today. Like other opiates, morphine and codeine... 

Hydrocodone is an opium analgesic (pain reliever) and antitussive (cough suppressant). It is related in structure to other alkaloids used as drugs, such as morphine and codeine (see Section 8). It increased 20% in number of prescriptions for one year. Its synthesis from codeine is by simple reactions. 

Catalytic reduction of codeine gives dihydrocodeine and Oppenauer oxidation (a ketone such as acetone and an aluminum alkoxide, the ketone being reduced to an alcohol) gives hydrocodone. Hydrocodone can also be prepared directly from codeine with a metal catalyst, which isomerizes the allylic alcohol to a ketone. Codeine is prepared by methylation of morphine, which is isolated from the opium poppy. Hydrocodone is more potent than codeine. Acetaminophen is a mild analgesic and is discussed in Section 8. 

Codeine occurs naturally in opium but the amount is too small to be useful. It is prepared from morphine by methylating the phenolic hydroxyl group with diazomethane, dimethyl sulfate, or methyl iodide. Codeine does not possess the same degree of analgesic potency as morphine but is used as an antitussive, a cough suppressant. Hydrocodone was discussed in Section 3.4. It is made from codeine. 

Oxycodone The synthesis of oxycodone, 4,5-epoxy-3-methoxy-14-hydroxy-iV-methyl-6-oxomorphinane (3.1.25), from 14-hydroxycodeinone (3.1.24) was described above. It can also be synthesized in other ways for example, by the oxidation of codeine using sodium dichromate in acetic acid [17], and is also a stractural analog of morphine and codeine. 

The above mentioned reactions are widely used in alkaloid modification. A good example of alkaloid modifications for clinical curation purposes are opioides. Morphine and codeine are natural products of Papaver somniferum. However, the codeine is naturally produced in small amounts. This is one reason why it is produced synthetically from morphine by modification. As codeine is the 3-0-methyl ether of morphine, the mono-O-methylation occurs in the acidic phenolic hydroxyl. Pholcodine is obtained by modification of morphine through alkylation with A-(chloroethyl)morpholine. Moreover, dihydrocodeine, hydro-morphone and heroine are also obtained from morphine through modifications. 

There are many legal medicines that use opiates or opiate-like substances. Most of the opiate-based medicines used today are not made from natural opiates, but are either synthetic or semi-synthetic. Synthetic opiate drugs are not actually opiates at all they are merely different chemicals that act like opiates. Semi-synthetics are those drugs that involve changing the chemical structure of a natural opiate. An example of this is heroin, which is a human-made variation of morphine. Morphine and codeine are the principal natural opiates used as medicines and what follows are descriptions of the other most frequently used opiate-based medicines. 

Opioid refers to any compound that acts like morphine, the most abundant alkaloid compound in opium. The term opioid includes substances that are derived from plants (such as morphine and codeine), those that occur naturally in the body (such as endorphins and enkephalins), and synthesized compounds (such as heroin and fentanyl). [Endorphins and enkephalins are discussed in Chapters 2 and 3. Fen-tanyi is discussed in Chapter 3.]... 

Morphine and codeine are both isolated from opium. Codeine (Schedule II), less potent that morphine, is biotransformed into morphine in the body and then further metabolized. 

Morphine and codeine as well as their natural and synthetic derivatives ultimately derived from opium ( opiates )... 

The introduction of heroin, although based on inaccurate observations and interpretation, undoubtedly influenced the trend and objectives of morphine research and marked the beginning of the search for an improved analgesic. During the 25 years after the introduction of heroin, other morphine derivatives were incorporated into medical practice some of which are still being used today. These include dihydrocodeine, differing from codeine only in the saturation of one double bond, hydrocodone... 

Morphine and codeine biosynthesis (Samuelsson, 1999 Herbert et al., 2000 Novak et al., 2000) Studies on the biosynthesis of morphine have been carried out mainly on cell cultures mainly of Coptis japonica and species of Thalictrum. Two enzymes (tyrosine decarboxylase and phenolase) catalyze the formation of dopamine from one molecule tyrosine. Dopamine is also the key intermediate in the biosynthesis of mescaline. 

In order to understand the continuation of the biosynthesis of codeine and morphine from reticuline, the structure for (S)-reticuline can be written as follows ... 

---