Salicylates structure

One of the hydroxybenzoic acids is known by the common name salicylic acid Its methyl ester methyl salicylate occurs in oil of wintergreen Methyl salicylate boils over 50°C lower than either of the other two methyl hydroxybenzoates What is the structure of methyl salicylate Why is its boiling point so much lower than that of either of its regioisomers ... 

Phenolic resins were the first totally synthetic plastics invented. They were commercialized by 1910 [I]. Their history begins before the development of the structural theory of chemistry and even before Kekule had his famous dreams of snakes biting their tails. It commences with Gerhardt s 1853 observations of insoluble resin formation while dehydrating sodium salicylate [2]. These were followed by similar reports on the behavior of salicylic acid derivatives under a variety of reaction conditions by Schroder et al. (1869), Baeyer (1872), Velden (1877), Doebner (1896 and 1898), Speyer (1897) and Baekeland (1909-1912) [3-17]. Many of these early reports appear to involve the formation of phenolic polyesters rather than the phenol-aldehyde resins that we think of today. For... 

In this bromoaspirin-inactivated structure, Ser , which lies along the wall of the tunnel, is bromoacetylated, and a molecule of salicylate is also bound in the tunnel. Deep in the tunnel, at the far end, lies Tyr, a catalytically important residue. Heme-dependent peroxidase activity is implicated in the formation of a proposed Tyr radical, which is required for cyclooxygenase activity. Aspirin and other NSAIDs block the synthesis of prostaglandins by filling and blocking the tunnel, preventing the migration of arachidonic acid to Tyr in the active site at the back of the tunnel. 

Chemical Name 2, 4 -Difluoro4-hydroxy-[ 1,1 -biphenyl] -3<arboxylic acid Common Name Difluorophenyl salicylic acid Structural Formula cooh... 

The acid itself (or the sodium salt) is a valuable drug in the treatment of arthritis. But the most widely known derivative of salicylic acid is aspirin, which has ihe following structure ... 

Possible Precursor Compounds Structural Significance Salicylates... 

NSAIDs are of diverse chemical structures salicylates (aspirin, sulphasalazine), indole acetic acids (indomethacin, etodolac), heteroaryl acetic acids (diclofenac), arylpropionic acids (ibuprofen, naproxen), anthranilic acids (mefenamic acid) and enolic acids (piroxicam, meloxicam). 

Samarium, tris(triphenylphosphine oxide)bis-(diethyldithiophosphato)-structure, 1,78 Samarium complexes dipositive oxidation state hydrated ions, 3, 1109 Samarium(III) complexes salicylic acid crystal structure, 2, 481 Sampsonite, 3, 265... 

Scheme 43 Structure and retrosynthetic analysis of the salicylate macrolides salicylihalamide A (215a) and B (215b) by various groups [103]...

The complexes of aromatic hydroxy carboxylic acids (salicylic acid and its isomers) with [Bu2Sn(IV)] and [Ph3Sn(IV)] were obtained. The FT-IR and Raman spectra clearly demonstrated that the organotin(IV) moieties react with the O, O) atoms of the ligands. It was found that in most cases the -COO group chelated to the central atoms, but monodentate coordination was also observed. The complexes probably have polymeric structures. 

The following abbreviations are used salenH2 = bis(salicylalde-hyde)ethylenediimine, salH = salicylaldehyde, SAB = 2-hydroxy-iV-(2-hydroxybenzylidine)aniline dianion, SAT = 2-(o-hydroxy-phenyDbenzothiazoline dianion, SAP = iV-(2-hydroxyphenyl)salicyl-adldimine dianion, and HMPT = hexamethylphosphoric triamide , and structures marked with an asterisk ( ) are polymeric, usually by in-termolecular association. 

Fig. 3.ia-c. Chemical structures of Jessner s Peel components (a Salicylic acid, b Resorcinol, and c Lactic acid)... 

Only four years after Kekule proposed the ring structure for benzene, and before the configuration of salicylic acid was established, Kraut concluded on the basis of sound chemical evidence that the products obtained on heating acetylsalicylic acid possess chain structures formed through intermolecular esterification. He assigned the dimeric and tetrameric formulas... 

Merola reported the preparation of hydrido(carboxylato)iridium(lll) complexes, mer-[lrCl(0C(0)R)(H)(PMe3)3] (90) (R = Ph, Me), by oxidative addition of acetic acid or benzoic acid to [Ir(cod)(PMe3)3]Cl (67) [46]. The structure of 90 (R = Ph) in which the carboxylato ligand coordinates as an T -ligand, was confirmed by X-ray analysis. The reaction of 67 with salicylic acid yielded the product 91, which resulted from activation of the O-H bond of the carboxylato but not of the hydroxo group (Scheme 6-13). 

As the majority of stabilisers has the structure of aromatics, which are UV-active and show a distinct UV spectrum, UV spectrophotometry is a very efficient analytical method for qualitative and quantitative analysis of stabilisers and similar substances in polymers. For UV absorbers, UV detection (before and after chromatographic separation) is an appropriate analytical tool. Haslam et al. [30] have used UV spectroscopy for the quantitative determination of UVAs (methyl salicylate, phenyl salicylate, DHB, stilbene and resorcinol monobenzoate) and plasticisers (DBP) in PMMA and methyl methacrylate-ethyl acrylate copolymers. From the intensity ratio... 

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