Salicylic compounds

L. Simonsen, A. Jorgensen, E. Benfeldt, and L. Groth. Differentiated in vivo skin penetration of salicylic compounds in hairless rats measured by cutaneous microdialysis. Eur. J. Pharm. Sci. 21 379-388 (2004). 

Pharmacology Olsalazine sodium is a sodium salt of a salicylate compound that is effectively bioconverted to 5-aminosalicylic acid (mesalamine 5-ASA), which has anti-inflammatory activity in ulcerative colitis. Approximately 98% to 99% of an oral dose will reach the colon, where each molecule is rapidly converted into 2 molecules of 5-ASA by colonic bacteria. The liberated 5-ASA is absorbed slowly, resulting in very high local concentrations in the colon. 

Hoffman s acetylsalicylic acid competed with the other salicylate compounds after its initial synthesis. In 1899 Hoffman s employer, the Bayer Company, founded in 1861 by Friedrich Bayer (1825-1880), began to market acetylsalicylic acid under the name Aspirin. The term aspirin was derived by combining the letter a from acetyl and spirin from spiric acid. Spiric acid is another name for salicylic acid found in plants of the genus Spirea. Bayer pro-... 

N.A. Viola tricolor L. Saponins, mucilage, violin, salicylic compounds, tannins.100,114 Diuretic, diaphoretic, tonic, antiinflammatory, blood-purifying properties. 

Salicylamide reportedly exerts a moderately quicker and deeper analgesic effect than aspirin. Long-term studies on rats revealed no untoward symptomatic or physiological reactions. Its metabolism differs from that of other salicylic compounds, and it is not hydrolyzed to salicylic acid." Its analge.sic and antipyretic activity is probably no greater than that of aspirin, and possibly less. It can be used in place of salicylates, however, and is particularly useful for patients with a demonstrated sensitivity to salicylates. It is excreted much more rapidly than other salicylates, which probably accounts for its lower toxicity and. thus, does not permit high blixHl levels. 

Tautz L, Bruckner S, Sareth S et al (2005) Inhibition of Yersinia tyrosine phosphatase by furanyl salicylate compounds. J Biol Chem 280 9400-9408... 

As well as being counter-irritants, salicylate compounds are hydrolyzed in the dermal and subcutaneous tissues to salicylic acid and have an anti-inflammatory action, although the exact mechanism of action of topical salicylates is still unclear. Salicylates may interfere with the activity of transcription factors and kinases involved in inflammatory processes, but do not appear to work through COX inhibition. In fact, data suggest that salicylates are approximately 100-fold less potent as inhibitors of COX-2 relative to ASA. 

The salicylate compounds used topically share with aspirin the common metabolic breakdown product, free salicylate (see section on aspirin earlier in this text), which is primarily responsible for the toxicity observed. On average, 12-20% of the dose of methyl salicylate is absorbed through the skin. Methyl salicylate is readily hydrolyzed to salicylate, although some methyl salicylate is found in blood. Some unchanged methyl salicylate is excreted in urine as hydrolysis is relatively slow in humans. 

C7H9N402- M.p. 337 C, an alkaloid obtained from cacao seeds or prepared synthetically. Constitutionally it is similar to caffeine, and is also a weak base. It is usually administered as the sodium compound combined with either sodium ethanoate or sodium salicylate, and is employed almost entirely as a diuretic. Physiologically theobromine resembles caffeine, but its effect on the central nervous system is less, while its action on the kidneys, is more pronounced. 

Note. A compound may yield more than one product, e.g., salicyl amide, HO C,H,CONH, will give ammonia and phenol. Sulphanilamide will give ammonia and aniline. 

Choice of solvent for recrystallisation. Obtain small samples (about 0 5 g.) of the following compounds from the storeroom (i) salicylic acid, (Li) acetanilide, (iii) m-dinitrobenzene, (iv) naphthalene, and (v) p-toluene-sulphonamide. Use the following solvents distilled water, methylated spirit, rectified spirit, acetone, benzene and glacial acetic acid. 

The key compound m the synthesis of aspirin salicylic acid is prepared from phe nol by a process discovered m the nineteenth century by the German chemist Hermann Kolbe In the Kolbe synthesis also known as the Kolbe—Schmitt reaction, sodium phen oxide IS heated with carbon dioxide under pressure and the reaction mixture is subse quently acidified to yield salicylic acid... 

Many pharmaceutical compounds are weak acids or bases that can be analyzed by an aqueous or nonaqueous acid-base titration examples include salicylic acid, phenobarbital, caffeine, and sulfanilamide. Amino acids and proteins can be analyzed in glacial acetic acid, using HCIO4 as the titrant. For example, a procedure for determining the amount of nutritionally available protein has been developed that is based on an acid-base titration of lysine residues. ... 

Many pharmaceutical compounds contain chromophores that make them suitable for analysis by UV/Vis absorption. Products that have been analyzed in this fashion include antibiotics, hormones, vitamins, and analgesics. One example of the use of UV absorption is in determining the purity of aspirin tablets, for which the active ingredient is acetylsalicylic acid. Salicylic acid, which is produced by the hydrolysis of acetylsalicylic acid, is an undesirable impurity in aspirin tablets, and should not be present at more than 0.01% w/w. Samples can be screened for unacceptable levels of salicylic acid by monitoring the absorbance at a wavelength of... 

SALICYLIC ACID AND RELATED COMPOUNDS] (Vol 21) l-Acetamido-2-pyrrolidinone [7491-74-9]... 

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