A-phenylacetic acid

Diclofenac is a phenylacetic acid derivative, non-steroidal anti-inflammatory drug. It is available as the potassium and sodium salts. Potassium salts are slightly more soluble than the sodium salts. Diclofenac can be used in breastfeeding mothers since the amount that passes through breast milk is too small to be harmful to the baby. However, diclofenac is contraindicated in pregnancy, especially during the last trimester. 

Cyclopentolate Cyclopentolate, 2-(dimethylamino)ethylic ester of 1-hydroxycyclopentane-a-phenylacetic acid (14.1.39), is synthesized by the esterification of a-(l- droxycylopentyl) phenylacetic acid (14.1.38) using 2-dimethylaminoethylchloride, a-(l- Hydroxycyclopentyl) phenylacetic acid (14.1.38) is synthesized by reacting the sodium salt of phenylacetic acid with cyclopentanone in the presence of isopropylmagnesium bromide [30]. 

Diclofenac Voltaren) is a phenylacetic acid derivative that is a potent inhibitor of COX and that has analgesic, antiinflammatory, and antipyretic effects. Its use is accompanied by side effects similar to those of other NSAIDs. Indications for the drug include rheumatoid arthritis, osteoarthritis, and ophthalmic inflammation (use of an ophthalmic preparation). 

Problem 16.63 Write formulas for each of the following (a) phenylacetic acid, (b) phenylethanoic acid, (c) 2-methylpropenoic acid, (d) ( )-butenedioic acid, (e) ethanedioic acid, (/) 3-methylbenzenecarboxylic acid. 

Diclofenac is a phenylacetic acid derivative that is relatively nonselective as a COX inhibitor. Pharmacokinetic and dosage characteristics are set forth in Table 36-1. 

Diclofenac is a phenylacetic acid derivative used mainly as sodium salt for the treatment of various pain and inflammation. Intramuscular injection occasionally causes tissue damage at the injection site. Suppositories may cause local irritation transient burning and stinging are reported when used for the eye and large doses can cause aplastic anemia.14... 

Figure S.21 Resulting chromatogram at the optimum conditions predicted by figure S.20. pH = S.8 concentration of n-octylamine = 3.2 mM. ODS column mobile phase methanol-water (20/80) with 0.010 M acetate buffer. Solutes E = phenylethylamine, P = phenylalanine, V = vanillic acid, C = trans caffeic acid, M = trans p-coumaric acid, F = trans ferulic acid, A = phenylacetic acid, H = hydrocinnamic acid and N = trans cinnamic acid. Figure taken from ref. [559]. Reprinted with permission. 

Difenpiramide, a phenylacetic acid derivative, is less efficacious but has fewer adverse effects than indometacin or phenylbutazone. The most frequent reactions are in the gastrointestinal tract and skin (1). However, gastrointestinal tolerance is, as one would expect, better (2). 

The passing of the years has not diminished the interest in photolabile protecting groups. Many such systems are available and have been described in the literature. A new method has been proposed for the protection of amino acids. This involves the conversion of the amino acid into the phenacyl derivatives 120. Irradiation of these derivatives in a buffered aqueous solution results in the release of the amino acid and the transformation of the phenacyl group into a phenylacetic acid. This occurs via the triplet state within which there is intramolecular displacement of the amino acid moiety as represented in 121. The resultant intermediate 122 undergoes ring opening by attack by water to afford the... 

The carbonylation of a benzyl halide in the presence of iron pentacarbonyl to give a phenylacetic acid may serve to exemplify the interaction of a metal carbonyl, carbon monoxide, PT catalyst, aqueous sodium hydroxide, and the substrate [79]. Fe(CO)5 is attacked by QOH at the interphase, and the species formed is extracted into the depths of the oganic phase, where it reacts with CO and benzyl halide (Eqs. 13 and 14). This new anion 3 is the actual catalyst. It reacts with a second benzyl halide to give a non-ionic intermediate 4 (Eq. 15). By insertion of CO and attack of QOH, 4 is decomposed to the reaction product under regeneration of 3 (Eq. 16). Thus, the action of the PT catalyst is twofold. Firstly it transports the metal carbonyl anion. More important seems to be its involvement in the (rate-determining) decomposition step. A basically similar mechanism was proposed for cobalt carbonyl reactions [80], which have been modified somewhat quite recently (see below). 

Tolmetin sodium is a NSAID, which decreases inflammation, pain, and fever, probably through inhibition of cyclooxygenase activity and prostaglandin synthesis. It is indicated in the treatment of chronic and acute rheumatoid arthritis and osteoarthritis and juvenile rheumatoid arthritis. Tolmetin and ketoroiac are structurally related heteroaryl acetic acid derivatives with different pharmacological features. Diclofenac is a phenylacetic acid derivative that was developed specifically as an antiinflammatory agent. 

Flash photolytic Wolff rearrangement of a-cyanodiazoacetophenone (210) produces a-cyano-a-phenylacetic acid (211) via hydration of the ketene intermediate.89... 

Unlike lactic acid, mandelic acid (7) occurs in nature only in small amounts and is therefore more expensive. Formerly, it was obtained by resolution of the racemate with a chiral base, such as l-phenylethylamines or ephedrine6, but enantioselective reductions of a-oxo-a-phenylacetic acid by chemical or biochemical methods have become feasible (Section D.2.3.I.). Esters of mandelic acid, e.g.. 8. can be prepared by any convenient esterification technique (see. for example, refs 7 and 46) and have been used for enantioselective protonation reactions (Sections C. and D.2.I.). Similar to the corresponding lactic esters, fumaric acid derivatives 9 are obtained from the mandelic esters and used as chiral dienophiles in diastereoselective Diels Alder reactions (Section D. 1.6.1.1.1.2.2.1.). 

Tolmetin and ketorolac are structurally related heteroaryl acetic acid derivatives with different pharmacological features. Diclofenac is a phenylacetic acid derivative that was developed specifically as an anti-inflammatory agent. 

It is a phenylacetic acid derivative which has analgesic, antipyretic and anti-inflammatoiy actions. It is mostly employed in the treatment of rheumatoid arthritis and other rheumatic disorders. 

Ans. (a) 2-Methylpropanoic acid, (b) butanone or ethyl methyl ketone, (c) benzoic anhydride, (e) 1-methoxypropanone or methoxyacetone, (/) methyl propanoate, (g) hydroxymethyl phenyl ketone, (A) phenylacetic acid, and (/) propanoyl chloride. 

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