Cocaine chemical properties

The toxicological or cumulative effect of illicit drugs on the ecosystems has not been studied yet. Moreover, their fate and transport in the environment is to a big extent still unknown. Due to their physical-chemical properties (octanol-water partition coefficient, solubility, etc.) some of them, such as cannabinoids, are likely to bioaccumulate in organisms or concentrate in sediments whereas the rest, much more polar compounds, will tend to stay in aqueous environmental matrices. However, continuous exposure of aquatic organisms to low aquatic concentrations of these substances, some of them still biologically active (e.g., cocaine (CO), morphine (MOR) and MDMA) may cause undesirable effects on the biota. 

Inhalant abuse is also termed volatile solvent abuse. It should be noted that many drugs besides those classified as inhalants can be administered by inhalation, including marijuana, cocaine, heroin, methamphetamine, fentanyl patches, and nicotine. These drugs are not volatile solvents and have different physical and chemical properties therefore, they are not classified as inhalants. Inhalants are chemicals that are volatile, meaning they can readily vaporize from... 

It is found that by limiting consideration to molecules with only one chiral center and therefore only one pair of enantiomers the usual physical and chemical properties are identical in a symmetrical environment. However, rates of reactions, even reactivity (e.g., metabolism reactions) and binding propensities may differ significantly in an asymmetric bioenvironment. There are cases where no differences are demonstrable. Both + and -cocaine are equipotent local anesthetics. Similarly, both enantiomers of chloroquine are equally effective antimalarial compounds. It is possible that in these instances the centers of asymmetry do not participate in drug-receptor interactions, or, more likely, that the interaction may involve only one or two points of contact. 

Psychotropic compounds, such as caffeine and nicotine, can exist in air as a result of their release in tobacco smoke or when certain drugs or essences are inhaled as vapors. These psychotropic substances belong to various classes of organic compounds with different physico chemical properties and different routes of release into the environment, so they may exist in the gaseous or asparticulates and as native compounds or derivatives. For instance, nicotine is mostly gaseous when it is a free base, but combines with tobacco smoke particles when in acidic form (Liang and Pankow, 1996). Cocaine and heroin in the atmosphere presumably exist mainly as solid particulates (Dindal et al., 2000 Cecinato and Balducci, 2007). 

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. 

Many pharmacologically active organic chemicals fonnd in natnre are alkaloids. In general, these componnds contain one or more nitrogen atoms, which in turn impart some basicity to the molecnle. Well-known alkaloid examples are caffeine, cocaine, codeine, ephedrine, morphine, nicotine, qninine, and scopolamine. Heroin is derived from morphine by a chemical modification that increases lipophilicity, making the heroin molecnle inherently more pharmacologically potent than morphine. The exhibition of its basic properties by an alkaloid (Aik) involves (by definition) the acceptance of a proton H+ according to ... 

The first clinical uses of a local anesthetic agent occurred in 1884, when cocaine was employed as a topical agent for eye surgery and to produce a nerve block. These events inaugurated a new era, that of regional anesthesia. New applications were developed, including spinal, epidural, and caudal anesthesia. The search for a better local anesthetic led to chemical synthesis of a number of other compounds that have more selective local anesthetic properties and few systemic side effects. 

The chemical search for synthetic substitutes started in 1892 and gave rise to several compounds with improved properties which largely replaced the naturally occurring cocaine. 

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. 

Cocaine is a CNS stimulant that affects blood vessels and pupils, and increases body temperature, heart rate, and blood pressure. The euphoric effects of cocaine are quick and include reduced fatigue and mental clarity, as well as hyperstimulation. Research reports that the faster the absorption, the shorter the duration of action. The effects of cocaine in humans are variable (e.g., feeling of restlessness, irritability, and anxiety). Cocaine has powerful neuropsychological-reinforcing properties that are responsible for its repeated compulsive use. In some cases, the first dose may prove fatal. Cocaine-related death may be due to cardiac arrest or convulsion followed by respiratory arrest. In drug abuse, people mix cocaine with alcohol, leading to a chemical complex called cocaethylene, which intensifies the euphoria but can culminate in death. 

Alkaloids are widespread in plants and include some very well-known poisons (notably coniine and strychnine), hallucinogens (morphine, cocaine and muscimol) and other potentially lethal compounds that are nevertheless used in medical practice (e.g. atropine, codeine, colchicine and morphine). As indicated by the preliminary snap-shot above, alkaloids typically have names ending in -ine and which are often related to the plant source or properties. Thus, morphine was named after Morpheus (the God of sleep) and coniine derives from Conium maculatum (hemlock), the plant used in the judicial murder of Socrates (399 BC). Various chemical tests for alkaloids are used as preliminary indicators of alkaloid presence in crude plant extracts. Finally, it should be noted that alkaloids can also exist as jVoxides of the alkaloid base. 

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. 

The importance of cocaine in surgery has led to the study of its chemical constitution and to the preparation, by synthetic methods, of analogous compounds having the beneficial anesthetic properties... 

Two well-known alkaloids, cocaine (3.11) and atropine (3.12), are ester derivatives of the 8-azabicyclo[3.2.1]octane ring system. Cocaine, isolated from a variety of the poppy plant, has been used as a topical anesthetic, but it is highly addictive if it enters the bloodstream and is now a controlled substance. Atropine, however, is highly useful in medicine with anticholinergic properties. It is isolated from the Belladonna plant and has been used for many years to dilate the pupil of the eye. It is also an effective antidote to poisoning by anticholinesterase chemicals, when these are used as insecticides or in extremely toxic form as chemical warfare agents. 

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... 

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