Paraldehyde Alcohol

Alcohol. Along with several bromide preparations and paraldehyde, alcohol has often been used to relieve anxiety. Due to the marked untoward social and medical consequences of frequent use, alcohol has no place in the treatment of anxiety. Unfortunately, the inappropriate use of alcohol to self-medicate anxiety, depression, insomnia, or other symptoms often leads to alcoholism and therefore contributes to a signihcant public health problem. 

Severe myocardial disease or coronary occlusion psychoses hypersensitivity to disulfiram or to other thiuram derivatives used in pesticides and rubber vulcanization patients receiving or who have recently received metronidazole, paraldehyde, alcohol, or alcohol-containing preparations. 

Hypnotics-, sulfonal, trional, chloral hydrate, veronal, paraldehyde. Alcohol used as a hypnotic may be pleasant for the patient but the risk of habituation makes it dangerous and ineffective... 

On acetylation it gives acetanilide. Nitrated with some decomposition to a mixture of 2-and 4-nitroanilines. It is basic and gives water-soluble salts with mineral acids. Heating aniline sulphate at 190 C gives sulphanilic add. When heated with alkyl chlorides or aliphatic alcohols mono- and di-alkyl derivatives are obtained, e.g. dimethylaniline. Treatment with trichloroethylene gives phenylglycine. With glycerol and sulphuric acid (Skraup s reaction) quinoline is obtained, while quinaldine can be prepared by the reaction between aniline, paraldehyde and hydrochloric acid. 

Almost insoluble in cold water. Higher alcohols (including benzyl alcohol), higher phenols (e.g., naphthols), metaformaldehyde, paraldehyde, aromatic aldehydes, higher ketones (including acetophenone), aromatic acids, most esters, ethers, oxamide and domatic amides, sulphonamides, aromatic imides, aromatic nitriles, aromatic acid anhydrides, aromatic acid chlorides, sulphonyl chlorides, starch, aromatic amines, anilides, tyrosine, cystine, nitrocompounds, uric acid, halogeno-hydrocarbons, hydrocarbons. 

Broirjal has been prepared by brominating a solution of paraldehyde in ethyl acetate, and by passing bromine vapor through absolute alcohol. ... 

The oldest anti-anxiety agent is undoubtedly alcohol and it is certain that this drug is still routinely self-administered for this purpose. Towards the end of the eighteenth century, bromide salts were used to relieve conditions akin to anxiety despite the risk of a characteristic toxic delirium, known as bromism . Alternative treatments, such as paraldehyde and chloral hydrate, were also widely used but these too had adverse effects the former can cause psychosis but the latter is still used as a sedative and anaesthetic agent. 

The procedure given above is essentially a large-scale adaptation of that of Filachione.2 Bromoacetal has been prepared by the bromination of acetal directly,3 or in the presence of calcium carbonate 4 by action of sodium ethoxide on a,/3-dibromodiethyl ether by bromination of paraldehyde followed by action of ethyl alcohol 6 and by the action of ethyl alcohol on bromoacetal-dehyde.7... 

METHYL ISOBUTYL KETONE n-PENTYL FORMATE n-BUTYL ACETATE sec-BUTYL ACETATE tert-BUTYL ACETATE ETHYL n-BUTYRATE ETHYL ISOBUTYRATE ISOBUTYL ACETATE n-PROPYL PROPIONATE CYCLOHEXYL PEROXIDE DIACETONE ALCOHOL 2-ETHYL BUTYRIC ACID n-HEXANOIC ACID 2-ETHOXYETHYL ACETATE HYDROXYCAPROIC ACID PARALDEHYDE... 

It is interesting to note that one of the founders of modern psychiatry, Kraepelin, listed only nine substances that were available for the treatment of psychiatric illness in the 1890s. These were opium, morphine, scopolamine, hashish, chloral hydrate, a barbiturate, alcohol, chloroform and various bromides. Later Bleuler, another founder of modern psychiatry, added paraldehyde and sodium barbitone to the list. Thus psychopharmacology is a very recent area of medicine which largely arose from the chance discovery of chlorpromazine by Delay and Deniker in France in 1952, and of imipramine by Kuhn in Switzerland in 1957. 

Caseous hydrogen chloride (2 to 31/rnin) is introduced into a mixture of 1.0 mol of propargyl alcohol (freshly distilled under reduced pressure) and 0.33 mol of paraldehyde, while keeping the temperature between -15 and -5 C. The introduction of gas is stopped when copious fumes escape from the outlet. The auxiliary equipment is removed and the flask allowed to stand for several min in a bath at -70 C. After solidification of the lower layer (concentrated aqueous HCl), the upper layer is cautiously decanted from the ice mass and vigorously... 

After 3 5 g of the hypnotic paraldehyde a qualitatively similar pattern of action was observed as with alcohol, although the stimulation phase was briefer and less pronounced and the paralysing action of the preparation was stronger. Following the intake of chloral hydrate and with the inhalation poisons the paralysing effect was still more pronounced. 

Volatile lipophilic substances like volatile general anaesthetics, ethyl alcohol, paraldehyde are excreted by the lungs. These volatile substances and certain gases that enter the body through the respiratory tract in the form of aerosol are excreted by this route. 

Condensation, of paraldehyde with diethyl malonate, 32, 54 of a-phene thyl chloride with diphenylacetonitrile, 39, 74 of phenylacetylene with ethyl orthoformate, 39, 59 of 1-phenylbiguanide with ethyl chloroacetate, 38,1 of potassium diphenylacetonitrile with benzyl chloride, 39, 73 of potassium trithiocarbonate with potassium chloroacetate, 39, 77 of sodium acetylacetonate to tetraacetylethane, 39, 61 of sodium formylacetone with cyano-acetamide, 32, 32 of tetracyanoethylene with N,N-dimethylaniline, 39, 68 of thiophene, paraldehyde, and hydrogen chloride, 38, 86 of thiourea with furfuryl alcohol, 36,66... 

Fulminate can be prepared from acetaldehyde instead of from alcohol, and from substances which are convertible into acetaldehyde, such as paraldehyde, metaldehyde, dimethyl- and diethyl-acetal. Methyl alcohol, formaldehyde, propyl alcohol, butyralde-hyde, glycol, and glyoxal do not yield fulminate. ... 

A = 10842 C6H12O3 CeHuO Paraldehyde Hexyl alcohol 124.35 157.85 Nonazeotrope 255... 

The chemical structures of some older and less commonly used sedative-hypnotics, including several barbiturates, are shown in Figure 22-3. Glutethimide (a piperidinedione) and meprobamate (a carbamate) are of distinctive chemical structure but are practically equivalent to barbiturates in their pharmacologic effects, and their clinical use is rapidly declining. The sedative-hypnotic class also includes compounds of simple chemical structure, including ethanol (see Chapter 23 The Alcohols), chloral hydrate, trichloroethanol, and paraldehyde (not shown). 

Historically the first sedative hypnotics to be introduced were the bromides in the mid 19th century, shortly followed by chloral hydrate, paraldehyde and urethane. It was not until the early years of this century that the first barbiturate, sodium barbitone, was developed and this was shortly followed by over 50 analogues, all with essentially similar pharmacological properties. The major breakthrough in the development of selective, relatively non-toxic sedative hypnotics followed the introduction of chlordiazepoxide in 1961. Most of the benzodiazepines in current use have been selected for their high anxiolytic potency relative to their central depressant effects. Because of their considerable safety, the benzodiazepines have now largely replaced the barbiturates and the alcohols, such as chloral hydrate and trichloroethanol, as the drugs of choice in the treatment of insomnia. 

Lithium chloride is soluble in many organic solvents 1 among them are alcohols, such as methyl alcohol, ethyl alcohol, higher alcohols, and glycerol aldehydes and ketones, such as acetaldehyde, paraldehyde, and acetone fatty acids, such as formic acid and acetic acid nitriles, such as acetonitrile and propionitrile phenol and bases, such as pyridine. Solution is sometimes accompanied by evolution of heat and formation of compounds, examples of those isolated 2 being... 

The degree of dissociation in acetone and pyridine is very small,4 but in formic acid it is of the same order as in water.5 For the alcohols and acetaldehyde it is considerable, and somewhat less for paraldehyde and acetonitrile.6 Acetic acid causes association to double molecules,7 which become partially dissociated with rise of temperature.8... 

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