- Il-8 receptor antagonists
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This invention relates to novel compounds of Formula (I), and compositions thereof, useful in the treatment of disease states mediated by the chemokine, Interleukin-8 (IL-8).
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- Il-8 receptor anatagonists
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This invention relates to novel compounds of Formula (I), and compositions thereof, useful in the treatment of disease states mediated by the chemokine, Interleukin-8 (IL-8).
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- Hydroxy diphenyl urea sulfonamides as IL-8 receptor antagonists
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Novell IL-8 compounds and methods of using them are provided.
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- N-nitroso-N,O-dialkylhydroxylamines: Preparation, structure, and mechanism of the hydronium ion catalysed solvolytic nitrous oxide extrusion reaction
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Eleven N-nitroso-N,O-dialkylhydroxylamines, RN(NO)OR′, have been prepared and the mechanisms of their hydronium ion catalysed solvolyses in aqueous solution which liberate nitrous oxide have been investigated. All reactions are first-order in substrate and first-order in hydronium ion, and the second-order rate constants at 25°C vary over a range of less than 140 in spite of considerable variation in substrate structure (R ranges from methyl to 4-methoxybenzyl to 2-adamantyl, for example) and changes in solvent composition (water with up to 50% methanol or 66% acetonitrile). Enthalpies and entropies of activation are qualitatively similar throughout the range (ΔH?= 72-93 kJ mol-1 and ΔS? = -19 to -57 J K-1 mol-1) which, with the product analyses, are accommodated by a mechanism involving pre-equilibrium protonation of the substrates followed by rate-limiting dissociation to give RN2O+ and HOR′. The oxodiazonium ion intermediate, RN2O+, then dissociates further to give the carbenium ion intermediate, R+, or suffers direct nucleophilic displacement of N2O by solvent (the external nucleophile) or by R′OH (the internal nucleophile liberated in the initial fragmentation). The carbenium ion, R+ (if formed), suffers nucleophilic capture either by solvent or by R′OH. When acetonitrile is the co-solvent (rather than methanol) for the N-(2-adamantyl) substrate 3g, the product of the Ritter reaction, 2-acetamidoadamantane, is detected. These nitrous oxide liberating reactions are compared with the nitric oxide liberating reactions of related N-nitrosohydroxylamines, and the origin of the difference between them is identified. The N(1)-nitroso group in the N,O-dibenzyl compound 3c is shown by X-ray crystallography to be essentially coplanar with the C and O atoms also bonded to N(1).
- Bhat, J. Ishwara,Clegg, William,Maskill, Howard,Elsegood, Mark R.J.,Menneer, Iain D.,Miatt, Peter C.
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p. 1435 - 1446
(2007/10/03)
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- α-Amino Acids as Chiral Educts for Asymmetric Products. The Synthesis of α'-Amino-α,β-ynones
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α-Amino acid isoxazolidides have been developed as educts for the preparation of optically pure α'-amino-α,β-ynones.The α-amino acids were first N-protected as their ethoxycarbonyl, tert-butoxycarbonyl, or phenylsulfonyl derivatives.The isoxazolidides then were formed by the simple, high yield acylation of isoxazolidine by in situ generated α-amino acid isobutyl carbonic anhydrides.Individual isoxazolidides of L-α-N-substituted alanine, phenylalanine, and methionine, when treated with lithium acetylide, lithium (trimethylsilyl)acetylide, or 1-hexynyllithium, gave high yields of the corresponding optically pure α,β-acetylenic ketones.
- Cupps, Thomas L.,Boutin, Raymond H.,Rapoport, Henry
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p. 3972 - 3979
(2007/10/02)
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- Amidinoureas
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A new class of chemical compounds and their process of preparation is described. These compounds have valuable properties as anti-secretory, anti-spasmodic, anti-ulcerogenic and anti-diarrheal agents.
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