3,5-Diisopropylsalicylic acid

Table 6.3. Cu(II)2(acetate)4 was found to be active in the initial test (carrageenan paw oedema) for anti-inflammatory activity, but inactive in the two follow-up anti-inflammatory screens (cotton wad granuloma and polyarthritis). Cupric chloride had no activity in any of these models of inflammation. Ligands such as anthranilic acid and 3,5-diisopropylsalicylic acid (3,5-DIPS) which were anticipated to be inactive were found to be so. However, their copper complexes were found to be potent anti-inflammatory agents in all three models of inflammation. These observations supported the notion that complexed copper is a more active anti-inflammatory form of copper and led to the suggestion that copper complexes of active anti-inflammatory agents might be more active than their parent anti-inflammatory drugs.

Electron spin resonance studies of the structural features of binuclear copper carboxylates suggest that the magnetic properties of biologically important molecules which contain copper may be better understood with this spectrophotometric technique [728]. Indeed, Greenaway, Norris and Sorenson used electron spin resonance to show that the copper complex of 3,5-diisopropylsalicylic acid is actually isolated as a binuclear complex, Cu(II)2(3,5-DIPS)4(H20)2, as opposed to the mononuclear structure, Cu(II)(3,5-DIPS)2, used throughout this manuscript, and organic solvates of this complex are also binuclear [729]. Electron spin resonance has also been used to study the orientation and mobility of Cu(II)[3-ethoxy-2-oxobutyralde-hyde bis(dimethylthiosemicarbazone)] in a bilayer lipid vesicle [730]. 

The anti-inflammatory activities of Cu(II)j(acetate)4, anthranilic acid (9), 3,5-diisopropylsalicylic acid (10), Cu(IlXanthranilate)2 (11) and Cu(II)(3,5-diiso-... 

Preston (1985) described the solvent extraction behavior of a large number of metal cations including rare earth nitrates in solutions of Versatic 10 (2-ethyl-2-methylheptanoic acid), naphthenic, 2-bromodecanoic and 3,5-diisopropylsalicylic acids in xylene. The last two acids extract metal cations under more acidic conditions, pH 1-2. For Versatic 10 the order of extraction of yttrium and lanthanides is La < Ce < Nd < Gd < Y < Ho < Yb and for naphthenic acids it is La < Ce < Y < Nd < Gd k Ho Yb. The lanthanides tend to form complexes of predominantly ionic nature. In the case of Versatic 10, the stability of the complexes increases uniformly with atomic number due to the increase in electrostatic energy as a result of the decrease in ionic radius. The primary branched naphthenic acid allows the formation of complexes with high coordination number, nine for La to Nd, eight and eventually six as the metal ionic radius decreases. In general, the extraction of a metal ion by a carboxylic acid H2A2 can be represented by the reaction... 

The infrared spectrum was identical to that reported. Cu Dips was synthesized by the procedure of Sorenson s with slight alteration (dried at 110°C for 4 h) m.p.l36-138°C (dec.), reported 142-144°C (dec.). Elemental analysis for C26H34O6CU was, calc. %C, 61.7. %H, 6.7 found %C, 60.3 %H, 6.6. Some Cu Dips solutions were prepared by adding CuCl2 2H20 to a solution of 3,5-diisopropylsalicylic acid (1.0 mM) containing sodium hydroxide (1.0 mM), so that the final concentration of Cu was 0.5 mM, in accord with prior procedures (see references in the metal section). 

The etherification between the epoxy and rubber oligomers can occur also at 353 K but requires such catalysts as chromium salts, diisopropylsalicylic acid, triphenylphosphine, betaine, triethanolamine, triethanolamine borate, benzyldiethylamine, or acetyltriethy-lene ammonium bromide. 

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