Salicyl alcohol, structure acidity

Late in the last century, a beginning was made in the task of simplifying the molecular structure of natural products while retaining the therapeutic action. It was hoped in this way to obtain substances which coiild be more easily synthesized and which might be free from toxic side effects introduced by unwanted parts of the molecule. The introduction of salicylic acid into medicine in 1875 was one of the earliest results of this endeavour, and this acid and its salts and derivatives such as aspirin replaced the use of willow bark, and the glucoside of salicyl alcohol which this bark contained. 

The chemical structures of the majority of FMs that have been studied in wastewater treatment are given in Figs. 1-3. Figure 1 shows a variety of FM structures that include alcohols, aldehydes, and ketones, including benzyl acetate (phenylmethyl ester acetic acid), methyl salicylate (2-hydroxy-methyl ester benzoic acid), methyl dihydrojasmonate (3-oxo-2-pentyl-methyl ester cyclopentaneacetic acid), terpineol (4-trimethyl-3-cyclohexene-1-methanol), benzyl salicylate (2-hydroxy-phenylmethyl ester benzoic acid), isobornyl acetate... 

The complexes [Ru(bpy)2L]+ (HL = acetylacetone, trifluoroacetylacetone, hexafluoroacetylace-tone, tropolone or dibenzoylmethane) have been prepared and characterized they act as catalysts for the oxidation of alcohols, 3,5-di-tert-butylcatechol and alkanes in the presence of appropriate co-oxidants." Perchlorate salts of [Os(bpy)2L] in which HL = salicylaldehyde, 2-hydroxyaceto-phenone or 2-hydroxynaphthaldehyde, are formed from reactions of [Os(bpy)2Br2] with HL. The structure of the salicylaldehyde derivative has been determined. Chemical and electrochemical oxidations of [Os(bpy)2L]" yield the corresponding low-spin Os species from which [Os(bpy)2L]+ can be regenerated." " [Ru(bpy)2L]" (HL = salicylic acid) has been prepared and structurally characterized as the tetrahydrate. Absorptions at 590 nm, 400 nm, and 290 nm in the electronic spectrum have been assigned to Ru bpy CT transitions electrochemical oxidations of the complex have been investigated." ... 

The monobasic saturated aromatic acids include benzoic, hippuric, toluic acids (three structures), phenylaceiic. phenylchloracelic, and dimethylben-zoic acid. Among the monobasic unsaturated acids are cinnamic, atropic. and phenylpropiomc acids. The saturated phenolic acids include gallic and salicylic acids. The alcohol acids include amygdalic, tropic, and man-delic acids. One example of an unsaturated monobasic phenolic acid is coumaric acid. 

Methyl salicylate, the active flavor compound in wintergreen candy, is composed of two fragments resembling structures from the above hst of compounds. These fragments are illustrated below and relate to salicylic acid and methyl alcohol. 

Since salicylic acid has both an alcohol functional group and a carboxylic acid functional group, it can undergo two different esterification reactions depending on which functional group reacts. For example, when treated with ethanoic acid (acetic acid), salicylic acid behaves as an alcohol and the ester produced is acetylsalicylic acid (aspirin). On the other hand, when reacted with methanol, salicylic acid behaves as an acid and the ester methyl salicylate (oil of wintergreen) is produced. Methyl salicylate is also an analgesic and part of the formulation of many liniments for sore muscles. What are the structures of acetylsalicylic acid and methyl salicylate ... 

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