Salicylic acid salicylate

Dennis Veere has ingested an unknown number of acetylsalicylic acid (aspirin) tablets. Acetylsalicylic acid is rapidly converted to salicylic acid in the body. The initial effect of aspirin is to produce a respiratory alkalosis caused by a stimulation of the "metabolic" central respiratory control center in the hypothalamus. This increases the rate of breathing and the expiration of COj. This is followed by a complex metabolic acidosis caused partly by the dissociation of salicylic acid (salicylic acid <-> salicylate -I- H, pKa = -3.5). 

The most common NSAID is aspirin, or acctylsalicvlic acid, whose use goes back to the late 1800s. It had been known from before the time of Hippocrates in 400 bc that fevers could be lowered by chewing the bark of willow trees. The active agent in willow bark was found in 1827 to be an aromatic compound called salicin, which could be converted by reaction with water into sal- icy I alcohol and then oxidized to give salicylic acid. Salicylic acid... 

Table 6.1 Formulations of salicylic acid salicylic acid ointment...

Take aspirin, for example. It has its origins in salicin, the active ingredient in willow bark. When salicin is hydrolysed it produces glucose and salicyl alcohol the latter can be oxidised to salicylic acid. Salicylic acid was also used as a medicine, but it caused irritation and bleeding in the stomach and intestines. However, when salicylic acid is treated with ethanoic anhydride, acetylsalicylic acid (aspirin) is produced. 

Various processes involve acetic acid or hydrocarbons as solvents for either acetylation or washing. Normal operation involves the recovery or recycle of acetic acid, any solvent, and the mother liquor. Other methods of preparing aspirin, which are not of commercial significance, involve acetyl chloride and salicylic acid, salicylic acid and acetic anhydride with sulfuric acid as the catalyst, reaction of salicylic acid and ketene, and the reaction of sodium salicylate with acetyl chloride or acetic anhydride. 

Polymer Selection. The polymer was selected on the basis of observations using salicylic acid-salicylate as analyte. The following organic polymers were examined polystyrene, methyl methacrylate-ethyl acrylate, Teflon, silicone rubber, PVC, and polyester. Ten-millimolar salicylic acid in 0.01 M HC1 was first extracted for 30 s and then back extracted with 0.1 M NaOH. Peak currents for back extractants (nA) were as follows PVC, 1780 methyl methacrylate-ethyl... 

One of the early pain-relieving drugs, aspirin, was introduced in 1899 by Felix Hoffman, working for the German pharmaceutical firm Bayer. In 1898 Bayer also introduced heroin as a pain killer. Aspirin2-4 is a man-made synthetic chemical compound, acetylsalicylic acid. It is made from salicylic acid. The ancient Greeks and native South Americans, among others, found that the bark of the willow tree eased fever and pain. We now know that this is because the bark contains salicylic acid. Salicylic acid is bitter and irritates the stomach (see also Chapter 1). 

Higuchi, T. Zuck, D.A. Investigation of some complexes formed in solution. III. Interactions between caffeine and aspirin, p-hydroxybenzoic acid, m-hydroxybenzoic acid, salicylic acid, salicylate ion, and butyl paraben. J. Am. Pharm. Assoc. (Wash). 1953, 42, 138-145. 

Diamond Yellow G.. Diamond Yellow R.. Cloth Brown R. Cloth Brown G. Cloth Orange il-amidobenzoic acid. 0-amidobenzoic acid. Benzidine.. . 1 1 Salicylic acid. Salicylic acid. 1 mol. salicylic acid, 1 mol. a-naphtholsulphonic acid. 1 mol. salicylic acid, 1 mol. /3 3-dioxynaphthalene. 1 mol. salicylic acid, 1 mol. resorcin. 

Aspirin occurs as while crystals or as a while cry.siallinc powder. It is slightly soluble in water (1 300) and soluble in alcohol (1 5). chloroform (1 17). and ether (1 15). Also, it dis.solvcs easily in glycerin. Aqueous solubility may be increased by using acetates or citrates of alkali metals, although these are said to decompose it slowly. It is stable in dry air. but in the presence of moi.stiirv. it slowly hydrol)/es into acetic and salicylic acids. Salicylic acid will crysialli/t out when an aqueous solution of a.spirin and sodium hydrov idc is boiled and then acidified. 

Salicylic acid G0-G3 Salicylic acid Salicylic acid Ester Anti-inflammatory No No No 337... 

Salicylic acid, salicylate esters and salts, acetaminophen, ibuprofen, morphine, phenylbutazone, indomethacin, sulindac, tolmetin, zomepirac... 

Titanium(iv) (d ).—K stopped-flow method has been used to study the reaction of Tpv substituted salicylic acids (salicylic, jff-resorcylic, and 5-nitro- and 5-amino-salicylic acids), and with diantipyrylmethane (L). Formation of mono-, bis-, and tris-complexes of L were investigated with structures [Ti(OH)2L] +, [Ti(OH)2L2] +, and [TiLal. The last reaction, involving the formation of the tris-complex, is the slowest step involved. 

The most likely impurity in the final product is salicylic acid itself, which can arise from incomplete reaction of the starting materials or from hydrolysis (reaction with water) of the product during the isolation steps. The hydrolysis reaction of acetylsalicylic add produces salicylic acid. Salicylic add and other compounds that contain a hydroxyl group on the benzene ring are referred to as phenols. Phenols form a highly colored complex with ferric chloride (Fe + ion). Aspirin is not a phenol, because it does not possess a hydroxyl group directly attached to the ring. 

Simultaneous Determination of Acetyl-salicylic Acid, Salicylic Acid, and Salicylamide in Plasma by Gas-Liquid Chromatography J. Pharm. Pharmacol. 27(6) 425-429 (1975) CA 83 172321k... 

The active component of willow bark was found to be salicin, a compound composed of salicyl alcohol bonded fo a unit of jS-D-glucose (Section 25.1). Hydrolysis of salicin in aqueous acid gives salicyl alcohol, which can be oxidized fo salicylic acid. Salicylic acid proved to be an even more effective reliever of pain, fever, and inflammation than salicin, without its extremely bitter taste. Unfortunately, salicylic acid causes severe irritation of the mucous membrane lining of the stomach. 

Hydroxy-5-[ 3-nitrophenyl)azo]benzoic acid, 9CI. 5-[(m-Nitrophenyl)azo]salicylic acid. Salicylic yellow. Metachrome yellow. C.L Mordant yellow 1. C.L 14025. Alizarin 2G. Chrome yellow G. Poloxal yellow GL. Numerous other proprietary names [6283-26-7]... 

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