Codeine description

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. ... 

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. 

Descriptions of methods for the estimation or detection of morphine and/or codeine in urine,213-218 body fluids,219 blood,220 blood stains,221 hair,222 and opium,223 for the examination of illicit heroin,224-226 and for the estimation of dihydromorphinone in plasma227 have been published, the effect of formaldehyde on the estimation of morphine has been examined,228 and a bioassay for morphine and naloxone has been described.229... 

The eyelids and upper lip can be treated with Lip Eyelid formula, without any analgesic other than a paracetamol plus codeine tablet to be taken 1 hour before treatment. Patients should also be given a clear description of the pain they will feel. By the time they have counted to 15, the pain will have gone. 

Figure 4. Regioselective Oxidative Coupling The final step for the completion of the pentacyclic ring system of the morphine alkaloids involves the closure of the C4-C5 ether bridge. Synthetic salutaridine has been transformed in vivo to thebaine, codeine, and morphine in Papaver sominiferum. Reduction of the dienone was proposed,30 and indeed, hydride reduction of salutaridine produces a mixture of two epimeric alcohols. However, upon feeding 7-3H labelled salutaridinol epimers to Papaver somniferum, only the S-isomer was converted into thebaine an indication that the reaction is enzyme mediated.31 >32 This finding contradicted earlier work by Barton in which the configuration of the alcohol was assigned as R (See description of Barton s synthesis, ref. 50).

Morphinan Alkaloids.—Extensive research on the biosynthesis of morphine (51) and related alkaloids in Papaver somniferum has allowed a detailed description of the pathway from the amino-acid tyrosine through reticuline (44), thebaine (46), and codeine (50) to morphine (51) (Scheme The incorporation of (R)-... 

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