Psychotomimetics structure

Psychotomimetic Drugs. Figure 2 Chemical structures of the dissociative anesthetics phencyclidine (PCP) and ketamine. Both are arylcycloalkylamine derivatives that are open channel blockers of the NMDA channel. 

Shulgin AT Hallucinogens, in Burger s Medicinal Chemistry, 4th Edition, Part 3. Edited by Wolff ME. New York, Wiley, 1981, pp 1109-1137 Shulgin AT Psychotomimetic drugs structure-activity relationships, in Handbook of Psychopharmacology, Vol 11. Edited by Iversen LD, Iversen SD, Snyder SH. New York, Plenum, 1978, pp 243-336... 

Shulgin, A.T. Psychotomimetic drugs Structure-activity relationships. In Iversen, L.L. Iversen, S.D. and Snyder, S.H., eds. Handbook of Psychopharmacology. Vol. 11. New York Plenum, 1978. pp. 243-333. Shulgin, A.T., and Carter, MF. Centrally active phenethylamines. 

Anderson, G.M. Braun, G. Braun, U. Nichols, D.E. and Shulgin, A.T. Absolute configuration and psychotomimetic activity. In Barnett, G. Trsic, M. and Willette, R., eds. Quasar Quantitative Structure Activity Relationships of Analgesics, Narcotic Antagonists, and Hallucinogens. National Institute on Drug Abuse Research Monograph 22. Rockville, MD the Institute, 1978. pp. 8-15. 

Shulgin, A.T. Sargent, T. and Naranjo, C. Structure-activity relationships of one ring psychotomimetics. Nature 221 537-541, 1969. 

Another characteristic of PCP which has been studied with great interest over the last 5 years, is the ability of PCP to produce a discriminative stimulus in monkeys, rats, and pigeons. As discussed elsewhere in this volume, by Browne, the discriminative stimulus properties of PCP are shared not only by other members of the arylcycloalkylamine class, but by psychotomimetic benzo-morphans and substituted dioxolanes. The structure-activity relationships (SAR) within and between these classes are virtually identical to those found when studying the displacement of 3H-PCP from its binding site in rat brain membranes. This correlation... 

Epinephrine. Is adrenaline. This substance is highly psychotomimetic in small doses (1 to 5 mg), but is not orally active because enzymes in the stomach destroy its molecular structure. To keep from having to inject it, put a dose under your tongue and let it absorb into your blood stream in this manner. 

The advances in isolation methods made possible a clarification of the chemistry of cannabis. In 1963, our group reisolated CBD and reported its correct structure and stereochemistry. A year later we finally succeeded in isolating pure A -tetrahydrocannabinol (A -THC), elucidated its structure, obtained a crystalline derivative and achieved a partial synthesis from CBD. Several years later, a minor psychotomimetically active constituent, A -THC, was isolated from marijuana. Whether this THC isomer is a natural compound, or an artifact formed during the drying of the plant, remains an open problem. 

There are various opioid receptors the three major classes of opioid receptors are mu (p), delta (5) and kappa (k) receptors. The p, receptor is the principal pain-modulating site in the CNS, mediating the action of morphine. There is considerable interest in the K receptor, which mediates a sedating analgesia with decreased addiction liability and respiratory depression and which allows for some structural flexibility. Unfortunately, the K receptor seems to be coupled to the sigma (a) receptor, which is implicated in psychotomimetic and dysphoric side effects. 

Nalbuphine hydrochloride is structurally related to oxymorphone and naloxone. It is approximately equipotent with morphine. Nalbuphine is metabolised in the liver to inactive metabolites. The plasma terminal half-life is approximately 5 h. The onset of analgesia is within 2-3 min of intravenous administration and 15 min after intramuscular injection, and lasts 3-6 h with an adult dose of 10 mg. With equi-analgesic doses, similar degrees of respiratory depression to that of morphine occur up to a dose of approximately 0.45 mg-kg-1. With higher doses a ceiling effect occurs. Sedation, possibly mediated by K-receptor activation, occasionally occurs. The incidence of psychotomimetic side effects is lower than with pentazocine. The abuse potential is low, but is can cause withdrawal symptoms in opioid-dependent subjects. It has occasionally been used to reverse opioid-induced respiratory depression. 

The first phase, typically identified in the literature by the use of the adjective "psychotomimetic," was characterized by dominance of a priori, structured models. Seriously underestimating the effects that such preconceptions might have on the content and aftereffects of the subjective experience, researchers variously reported that psychedelics mimicked mental illness (when given in a setting that provoked it), illuminated Freudian theory (when administered by a com-... 

Figure 15.7. Structures of the psychotomimetic compound phencyclidine and the structurally related dissociative anaesthetic ketamine.

Most ergot alkaloids stimulate the sympathetic structures-of the mesencephalon and diencephalon, particularly the hypothalamus, leading to a syndrome of excitation with mydriasis, hyperglycemia, tachycardia, etc. This syndrome may be closely related to the psychotomimetic effects of certain alkaloid derivatives, e.g., lysergic acid diethylamide. 

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