Cocaine chemical structure

Chemical Structures. Figure 1 shows the chemical structures for 14 phenylethylamine compounds. Nine of these compounds are used clinically as anorectics (ii-amphetamine, phentermine, diethylpropion, phenmetrazine, phendimetrazine, clotermine, chlorphentermine, benzphetamine, and fenfluramine). Four of these compounds are not approved for clinical use and are reported to have hallucinogenic properties (MDA, PMA, DOM, and DOET). The final compound ( /-ephedrine) is used clinically for bronchial muscle relaxation, cardiovascular, and mydriatic effects. Figure 2 shows the chemical structure for MDMA, the methyl analog of MDA. MDMA is not approved for clinical use and has been reported to produce both LSD-like and cocaine-like effects. 

Chemical structure of cocaine and synthetic local anesthetics. 

The addictiveness of a given substance goes beyond the chemical structure of the addictive drug itself (i.e., morphine, cocaine, or nicotine). The effects are also related to the dose and speed of delivery, as well as to other substances that might be part of the formulation. For example, just as the oral consumption of opioids and cocaine produce substantially less pronounced behavioral and physiological effects than intravenous or smoked consumption, slow release forms of nicotine produce generally less pronounced effects than smoked forms (Henningfield and Keenan 1993). Similarly, the free base or unprotonated forms of cocaine and... 

An alkaloid is a complex organic chemical substance found in plants, which characteristically combines nitrogen with other elements, has a bitter taste, and typically has some toxic, stimulant, analgesic effects. There are many different alkaloids, 30 of which are found in the opium plant. While morphine is the most important alkaloid in opium—for its natural narcotic qualities as well as providing the chemical structure for heroin—another alkaloid, codeine, is also sought after for its medicinal attributes. Other alkaloids include papaverine, narcotine, nicotine, atropine, cocaine, and mescaline. While the concentration of morphine in opium varies depending on where and how the plant is cultivated, it typically ranges from 3 percent to 20 percent. 

Many substances of widely different chemical structure abolish the excitability of nerve fibers on local application in concentrations that do not cause permanent injury and that may not affect other tissues. Sensory nerve fibers are most susceptible, so that these agents produce a selective sensory paralysis, which is utilized especially to suppress the pain of surgical operation. This property was first discovered in cocaine, but because of its toxicity and addiction liability, it has been largely displaced by synthetic chemicals. The oldest of these, procaine (novocaine), is still the most widely used. Its relatively low toxicity renders it especially useful for injections, but it is not readily absorbed from intact mucous membranes and is therefore not very effective for them. Many of its chemical derivatives are also used. They differ in penetration, toxicity, irritation, and local injury as well as in duration of action and potency. Absolute potency is not so important for practical use as is its balance with the other qualities. If cocaine is absorbed in sufficient quantity, it produces complex systemic actions, involving stimulation and paralysis of various parts of the CNS. These are mainly of toxicological and scientific interest. Its continued use leads to the formation of a habit, resembling morphinism. This is not the case with the other local anesthetics. 

This alkaloid was first isolated from Ephedra equisetina, a plant (ma huang) that has been used as medicine by the Chinese since antiquity. Most of the present supply is probably synthetic. Its chemical structure is closely related to epinephrine and tyramine, and differs from epinephrine chiefly by the absence of the two phenolic hydroxyls. Its effects on the circulation, intestines, bronchi, iris, etc., are superficially similar to those of epinephrine. It requires that larger doses be given but they are more lasting, due probably to ephedrine s much greater stability and resistance to oxidation. The effects can be produced by oral administration. Unlike epinephrine, it is not sensitized by cocaine or by denervation. From this, it has been argued that its point of attack is not sympathomimetic but muscular. It also stimulates the CNS. A number of isomers with similar actions are known. Ephedrine is used therapeutically in hay fever and asthma, in which it is less... 

Cocaine acts as a local anaesthetic, that is at the site of application, probably by interfering with transmission of nerve impulses by changing the permeability of the nerve to sodium ions. While the drug is no longer used for this purpose, many of the newer local anaesthetics are based on the chemical structure of cocaine. 

Pharmacologists often take refined natural drugs and change their chemical structures to vary their properties. A very simple change is to combine an insoluble drug from a plant with an acid to make a water-soluble salt. In this way the "freebase" form of cocaine, which is usually smoked because it will not dissolve, is turned into cocaine hydrochloride, a water-soluble compound that can be inhaled or injected. 

Amphetamines are synthetic stimulants that were invented in Germany in the 1930vS. Their chemical structures resemble those of adrenaline and noradrenaline, the body s own stimulants. Their effects resemble those of cocaine but arc much longer lasting. A single oral dose of amphetamine usually stimulates the body for at least four hours. 

This is the chemical structure of cocaine, C17H21NO4, the most common form of the drug smuggled into and used in the United States. Cocaine in its natural state is an alkaloid, which is not easily dissolved. When it is converted to cocaine hydrochloride, it is easier to snort or inject. 

The traditional method of drag development, at least in this century, has been to develop leads by first using, and then by isolating and identifying, the active chemical constituents from natural products, some of which may have been medicinally in use since antiquity. With the advent of modem organic chemistry some of these purified compounds were used directly (e.g., morphine, cocaine, atropine, quinine), and, once their chemical structures were ascertained, they became leads for hoped-for chemical modifications to achieve improved efficacy, less toxicity, or, at least, higher potency (e.g., dihydromorphinone, homatropine, acetylsalicylic acid). 

Since the discovery of cocaine in 1880 as a surgical local anesthetic, several thousand new compounds have been tested and found to produce anesthesia by blocking nerve conductance. Among these agents, oniy approximateiy 20 are ciinicaiiy available in the United States as local anesthetic preparations (Tabie 16.1). Tabie 16.2 contains chemical structures of the different types of agents in current or recent use. 

Fig. 3.55 The chemical structure and 3D model of cocaine. (Authors own work)...

One of the first uses of local anesthetics (LA) for anesthesia was in the late nineteenth century with William Halsted reporting a mandibular block and brachial plexus block using cocaine [37,38]. The chemical structure of local anesthetics in clinical use consists of an aromatic (lipophilic) benzene ring linked to an amino group (hydrophflic) via either an ester or an amide intermediate chain. The intermediate link classifies the local anesthetic as either an ester (procaine, chloroprocaine, tetracaine, and cocaine) or an amide (lidocaine, prilocaine, mepivacaine, bupi-vacaine, etidocaine, and ropivacaine). 

Fig. 2. Chemical structures of cocaine (1), methacrylic add (2) and ethylene glycol dimethyl acrylate (3).

The chemical structure of A -tetrahydrocannabinol, determined by Gaoni and Mechoulam in 1964, is illustrated in Figure 6.3. Unlike many other biologically active chemicals of plant origin, A -tetrahydrocannabinol is a highly hydrophobic molecule, a property that has hindered the progress on its mode of action for nearly three decades. Indeed, not only was A -tetrahydrocannabinol more difficult to handle experimentally than such hydrophylic alkaloids as cocaine or morphine, but also its preference for lipid... 

The validation method presented here was carried out by the team of C. Staub at the Forensic Laboratory of Geneva University. The point was to validate a method for the dosage of cocaine (COC) and its three main metabolites [ecgonine methy-lester (EME), anhydroecgonine methylester (AEME), and cocaethylene (COET)] in hair. Their chemical structures are presented in Figure 7.12. The internal standards used were cocaine-dj for COC and COET and ecgonin methylester-dj for EME and AEME (molecules deuterated on one of the methyl groups). 

FIGURE 7.12 Chemical structures of cocaine (COC) and its three main metabolites ecgo-nine methylester (EME), anhydroecgonine methylester (AEME), and cocaethylene (COET). 

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