- C-2 phenyl replacements to obtain potent quinoline-based Staphylococcus aureus NorA inhibitors
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NorA is the most studied efflux pump of Staphylococcus aureus and is responsible for high level resistance towards fluoroquinolone drugs. Although along the years many NorA efflux pump inhibitors (EPIs) have been reported, poor information is available ab
- Astolfi, Andrea,Barreca, Maria Letizia,Biavasco, Francesca,Cannalire, Rolando,Cecchetti, Violetta,Cedraro, Nicholas,Felicetti, Tommaso,Manfroni, Giuseppe,Mangiaterra, Gianmarco,Massari, Serena,Pietrella, Donatella,Sabatini, Stefano,Tabarrini, Oriana
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p. 584 - 597
(2020/02/15)
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- Development of N -methyl-(2-arylquinolin-4-yl)oxypropanamides as leads to PET radioligands for translocator protein (18 kDa)
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Translocator protein (18 kDa), known as TSPO, is a recognized biomarker of neuroinflammation. Radioligands with PET accurately quantify TSPO in neuroinflammatory conditions. However, the existence of three human TSPO genotypes that show differential affinity to almost all useful TSPO PET radioligands hampers such studies. There is an unmet need for genotype-insensitive, high-affinity, and moderately lipophilic TSPO ligands that may serve as leads for PET radioligand development. To address this need, we varied the known high-affinity TSPO ligand (l)-N,N-diethyl-2-methyl-3-(2- phenylquinolin-4-yl)propanamide in its aryl scaffold, side chain tether, and pendant substituted amido group while retaining an N-methyl group as a site for labeling with carbon-11. From this effort, oxygen-tethered N-methyl- aryloxypropanamides emerged as new high-affinity TSPO ligands with attenuated lipophilicity, including one example with attractive properties for PET radioligand development, namely N-methyl-N-phenyl-2-{[2-(pyridin-2-yl)quinolin- 4-yl]oxy}propanamide (22a; rat Ki = 0.10 nM; human TSPO genotypes Ki = 1.4 nM; clogD = 4.18). This article not subject to U.S. Copyright. Published 2014 by the American Chemical Society.
- Brouwer, Chad,Jenko, Kimberly,Zoghbi, Sami S.,Innis, Robert B.,Pike, Victor W.
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supporting information
p. 6240 - 6251
(2014/08/18)
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- Synthesis, crystal structure, and in vitro antitumor activities of copper(II) complexes containing tetradentate pyridine-based ligands
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Several new Cu(II) complexes of Schiff bases obtained by condensation of 2-[N-(α-picolyl)-amino]-benzophenone with different chiral amino acids were synthesized and characterized by physico-chemical and spectroscopic methods. The crystal structure of one
- Yang, Xin-Tao,Wu, Hao,Ma, Shi-Jun,Hu, Juan-Juan,Wang, Yong-Mei
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experimental part
p. 403 - 407
(2012/03/08)
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- Sequential Cu-catalyzed amidation-base-mediated camps cyclization: A two-step synthesis of 2-aryl-4-quinolones from o-halophenones
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(Chemical Equation Presented) A direct two-step method for the preparation of 2-aryl- and 2-vinyl-4-quinolones that utilizes a copper-catalyzed amidation of o-halophenones followed by a base-promoted Camps cyclization of the resulting N-(2-ketoaryl)amides is described. With CuI, a diamine ligand, and base as the catalyst system, the amidation reactions proceed in good yields for a range of aryl, heteroaryl, and vinyl amides. The subsequent Camps cyclization efficiently provides the desired 4-quinolones with the conditions that are described.
- Jones, Carrie P.,Anderson, Kevin W.,Buchwald, Stephen L.
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p. 7968 - 7973
(2008/02/13)
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- Virtually complete control of simple and face diastereoselectivity in the Michael addition reactions between achiral equivalents of a nucleophilic glycine and (S)- or (R)-3-(E-enoyl)-4-phenyl-1,3-oxazolidin-2-ones: Practical method for preparation of β-substituted pyroglutamic acids and prolines
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This study demonstrates a new strategy for controlling the stereochemical outcome of the Michael addition reactions between nucleophilic glycine equivalents and α,β-unsaturated carboxylic acid derivatives: The addition reactions between achiral Ni(II)-complex of the Schiff base of glycine with o-[N-α-pycolylamino]acetophenone and (S)- or (R)-3-(E-enoyl)-4- phenyl-1,3-oxazolidin-2-ones were shown to occur at room temperature in the presence of nonchelating organic bases and, most notably, with very high stereoselectivity at both newly formed stereogenic centers. Thus, the chiral 4-phenyl-1,3-oxazolidin-2-one moiety was found to control efficiently both face diastereoselectivities of the glycine derived enolate and the C,C double bond of the Michael acceptor. The new strategy developed in this work is methodologically superior to previous methods, most notably in terms of generality and synthetic efficiency. Excellent chemical yields and diastereoselectivities, combined with the simplicity of the experimental procedures, render the present method of immediate use for preparing various 3-substituted pyroglutamic acids and related amino acids (glutamic acids, glutamines, prolines, etc.) available via conventional transformations of the former.
- Soloshonok, Vadim A.,Ueki, Hisanori,Tiwari, Rohit,Cai, Chaozhong,Hruby, Victor J.
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p. 4984 - 4990
(2007/10/03)
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- (S)- or (R)-3-(E-enoyl)-4-phenyl-1,3-oxazolidin-2-ones: ideal Michael acceptors to afford a virtually complete control of simple and face diastereoselectivity in addition reactions with glycine derivatives.
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[formula: see text] Enantiomerically pure (S)- or (R)-3-(E-enoyl)-4-phenyl-1,3-oxazolidin-2-ones were found to serve as ideal Michael acceptors in addition reactions with achiral Ni(II) complexes of glycine Schiff bases. Virtually complete control of simple and face diastereoselectivity, observed in these reactions, combined with quantitative chemical yields renders this methodology synthetically superior to the previous methods.
- Soloshonok,Cai,Hruby
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p. 747 - 750
(2007/10/03)
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- Rational Design of Highly Diastereoselective, Organic Base-Catalyzed, Room-Temperature Michael Addition Reactions
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Via the rational design of a single-preferred transition state, stabilized by electron donor - acceptor-type attractive interactions, structural and geometric requirements for the corresponding starting compounds have been determined. The Ni(II) complex of the Schiff base of glycine with o-[N-α-picolylamino]acetophenone, as a nucleophilic glycine equivalent, and N-(trans-enoyl)oxazolidin-2-ones, as derivatives of an α,β-unsaturated carboxylic acid, were found to be the substrates of choice featuring geometric/conformational homogeneity and high reactivity. The corresponding Michael addition reactions were found to proceed at room temperature in the presence of catalytic amounts of DBU to afford quantitatively the addition products with virtually complete diastereoselectivity. Acidic decomposition of the products followed by treatment of the reaction mixture with NH4OH gave rise to the diastereomerically pure 3-substituted pyroglutamic acids.
- Soloshonok, Vadim A.,Cai, Chaozhong,Hruby, Victor J.,Van Meervelt, Luc,Yamazaki, Takashi
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p. 6688 - 6696
(2007/10/03)
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