Demerol structure

Morphine was known to the Sumerians and Egyptians as a very valuable pain killer in medicine it is also a powerful narcotic that is habit forming. A great deal of effort has been spent in finding a derivative of morphine that has its good properties, and less of its bad properties. Then, in 1944, demerol and methadone were discovered, which are even more powerful than morphine, but bear no structural relation to morphine. The leading theory now is that both morphine and methadone have the same T-shape, and may fit the receptor. 

The gold standard of opiate pain relievers is morphine. It was one of the first compounds extracted, isolated, and purified from the opium poppy, and it continues to be one of the most widely used pain relievers today. Morphine and other opiate drugs such as heroin, codeine, oxycodone, and hydrocodone have very similar chemical structures (Figure 3.2). However, other opiates such as fentanyl and meperidine (Demerol) have a slightly different structure (Figure 3.3). 

Enkephalins are pentapeptides that are synthesized by the body to control pain. They decrease the body s sensitivity to pain by binding to receptors in certain brain cells. Part of the three-dimensional structures of enkephalins must be similar to those of morphine and painkillers such as Demerol because they bind to the same receptors (Sections 30.3 and 30.6). 

Heroin, the diacetate ester of morphine, does not occur in nature but can be synthesized from morphine. As shown in Figure 17.5, their structures differ in only one kind of functional group. Heroin is much more addictive than morphine and for that reason has no legal use in the United States. Codeine, a methyl ether of morphine, is one of the alkaloids in opium and is used in cough syrup and for relief of moderate pain. Codeine is less addictive than morphine, but its analgesic activity is only about one-fifth that of morphine. One of the most effective substitutes for morphine is meperidine, whose structure was identified in 1931, is now sold as Demerol. It is less addictive than morphine. 

It has been discovered that there can be even further simplification in the structure of morphinelike analgesics. One such simplification is represented by meperidine, the hydrochloride salt of which is the widely used analgesic Demerol . 

The analgesic meperidine (Demerol) was developed in the search for analgesics without the addictive effects of morphine. As shown in these structural formulas, it represents a simplification of morphine s structure. 

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