Morphine-like analgesics

Dezocine (30) represents a class of bridged aminotetralins possessing morphine-like analgesic properties. It appears to be roughly equivalent in potency and addiction potential to morphine. The molecule combines molecular features of precedent aminotetralins and benzomor-phans and its structure fits the classical Morphine Rule. The 1-enantiomer is the more active and the p-epimer (equatorial NHj) is the active diastereomer. 

By conventional tests, secondary amine analogues of 4-phenylpiperidine analgesics lack activity (normorphine is equi-potent with morphine by the intra-cisternal route [48]) many secondary bases of the thebaines,(VII), however, are morphine-like analgesics. These findings lend support to the view that the low potencies reported for many nor-analogues of analgesics are due to distribution factors and not to the failure of such derivatives to associate at the receptor. 

The azacycloheptane (XXX), the most active non-piperidine derivative of the reversed ester series (7 X pethidine), was a typical morphine-like analgesic it... 

Activities and sites of antinociceptive action of morphine-like analgesics, 6, 79... 

Morphine-like analgesics are Binding experiments and investigations in pain models Selective have shown that the p-receptor and to a lesser degree the... 

Janssen, P.A. and Van der Eycken, C.A. The chemical anatomy of potent morphine-like analgesics, in Drugs affecting the central nervous system, edited by A. Burger, 1968, 25-60, Marcel Decker, New York. 

Bergman, F. and Elam, R. On the mechanism of action of 2-amino-4-methylpyridine, a morphine-like analgesic, Arch. Int. Pharmacodyn. 1980, 247, 275-282. 

In recent years there has been a major research effort, so far without success, to produce potent, centrally acting analgesics that do not have an abuse potential. The discovery of various types of opioid receptor, which may have different effects on central neurotransmitter function, may ultimately lead to the development of such a drug. In the meantime, the most widely used opioids, for example morphine, heroin (also called diacetylmorphine) and codeine are therapeutically effective but are liable to be abused and produce dependence. The structure of some of the morphine-like analgesics and their antagonists are shown in Figure 15.2. 

Erom the time. Small ct al. started their studies on the nmtphinc nucleus to the present, there has been much light died on the structural features connected with morphine-lile analgesic action. In a very thorough. study made for the United Nations Commission on Narcotics in I9SS. Braendcn oal. found that the features possessed by all known morphine-like analgesics were as follows ... 

Activities and sites of antinociceptive action of morphine-like analgesics. 6, 79 Adrenergic neurone blocking agents, 1, 161 Advances in penicillin research, 7, 1... 

Heroin (3,6-O-diacetylmorphine, diamorphine) was first synthesized from morphine by an English chemist, CR Wright, in 1874, and was introduced commercially as a morphine-like analgesic by the Bayer Company of Germany in 1898. Heroin was initially used as a morphine and codeine substitute for the treatment of tuberculosis and other respiratory illnesses. However, it quickly became apparent that this drug was more toxic than morphine and exhibited equivalent abuse liability and tolerance-... 

CH2CH2CIIJ) is stated" 2 to be a potent morphine-like analgesic vdth no nalorphine properties, yet possessing a good separation of analgesic from respiratory depressant properties. A compound ( K 5050) having a... 

Fio. 23. Structure foimulae of the agonists morphine and levorphanol. and of morphine-antagonists nalorphine and levalloiphan. For the morphine-like analgesic meperidine, the conventional (A) and adapted (B) formula is given. 

Fio. 24 Basic structure of morphine-like analgesics and modified form of model of the morphine-receptor. (Beckett. A. H. and Casy. A. F.. 1954.)... 

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