Listar CIQUS-Artigos por título
Mostrando ítems 1-20 de 53
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Amide-Directed Formation of Five-Coordinate Osmium Alkylidenes from Alkynes
(American Chemical Society, 2015-12-31)The amide-directed synthesis of five-coordinate osmium alkylidene derivatives from alkynes is reported. These types of complexes, which have been elusive until now because of the tendency of osmium to give hydride alkylidyne ... -
Analysis of the temperature dependence of the thermal conductivity of insulating single crystal oxides
(AIP Publishing LLC, 2016-10)The temperature dependence of the thermal conductivity of 27 different single crystal oxides is reported from ≈20 K to 350 K. These crystals have been selected among the most common substrates for growing epitaxial thin-film ... -
Anion recognition and induced self-assembly of an alpha,gamma-cyclic peptide to form spherical clusters
(Wiley, 2016-03-21)A cyclic octapeptide composed of hydroxy-functionalized γ-amino acids folds in a "V-shaped" conformation that allows the selective recognition of anions such as chloride, nitrate, and carbonate. The process involves the ... -
Antibiotic adjuvants – A strategy to unlock bacterial resistance to antibiotics
(Elsevier, 2017-08-14)Resistance to available antibiotics in pathogenic bacteria is currently a global challenge since the number of strains that are resistant to multiple types of antibiotics has increased dramatically each year and has spread ... -
Chiral Coalition in Helical Sense Enhancement of Copolymers: The Role of the Absolute Configuration of Comonomers
(American Chemistry Society, 2017-12-14)Both the role of the absolute configuration and the tendency of a chiral monomer to promote a certain helical scaffold in a polyphenylacetylene (PPA) —that depends on the conformational composition at the pendant group— ... -
Chiral nanostructure in polymers under different deposition conditions observed using atomic force microscopy of monolayers: poly(phenylacetylene)s as a case study
(Royal Society of Chemistry, 2016-10-31)Dynamic poly(phenylacetylene)s (PPAs) adopt helical structures with different elongation or helical senses depending on the types of pendants. Hence, a good knowledge of the parameters that define their structures becomes ... -
Concise, enantioselective, and versatile synthesis of (−)-Englerin A Based on a platinum-catalyzed [4C+3C] cycloaddition of allenedienes
(WILEY-VCH Verlag GmbH, 2016-10-13)A practical synthesis of (−)-englerin A was accomplished in 17 steps and 11 % global yield from commercially available achiral precursors. The key step consists of a platinum-catalyzed [4C+3C] allenediene cycloaddition ... -
Coupling the folding of a β-hairpin with chelation-enhanced luminescence of Tb(III) and Eu(III) ions for specific sensing of a viral RNA
(Royal Society of Chemistry, 2016-01-10)Rational modification of a natural RNA-binding peptide with a lanthanide EDTA chelator, and a phenanthroline ligand yields a highly selective luminescent sensor. The sensing mechanism relies on the RNA-triggered folding ... -
A designed DNA binding motif that recognizes extended sites and spans two adjacent major grooves
(Royal Society of Chemistry, 2016-02-05)We report the rational design of a DNA-binding peptide construct composed of the DNA-contacting regions of two transcription factors (GCN4 and GAGA) linked through an AT-hook DNA anchor. The resulting chimera, which ... -
Discrete Cu(I) complexes for azide-alkyne annulations of small molecules inside mammalian cells
(Royal Society of Chemistry, 2018-01-15)The archetype reaction of “click” chemistry, namely, the copper-promoted azide–alkyne cycloaddition (CuAAC), has found an impressive number of applications in biological chemistry. However, methods for promoting intermolecular ... -
Fluorescence-Labeled Bis-benzamidines as Fluorogenic DNA Minor-Groove Binders: Photophysics and Binding Dynamics
(WILEY-VCH Verlag GmbH, 2014-11-21)In recent decades there has been great interest in the design of highly sensitive sequence-specific DNA binders. The eligibility of the binder depends on the magnitude of the fluorescence increase upon binding, related to ... -
A general route to chiral nanostructures from helical polymers: P/M switch via dynamic metal coordination
(Royal Society of Chemistry, 2017-05-16)A general method for the conversion of a polyphenylacetylene into its P or M helically oriented polymer, and into their corresponding P/M helical nanoparticles via dynamic metal coordination is presented. Addition of Mn+ ... -
Glycosyl Aldehydes: New Scaffolds for the Synthesis of Neoglycoconjugates via Bioorthogonal Oxime Bond Formation
(Georg Thieme Verlag, 2018-01-02)The straightforward preparation of glycosyl neoconjugates by oxime (or hydrazone) bond formation represents a key bioorthogonal tool in chemical biology. However, when this strategy is employed by reacting the reducing end ... -
Gold(I)-catalyzed [2 + 2 + 2] cycloaddition of allenamides, alkenes and aldehydes: a straightforward approach to tetrahydropyrans
(Royal Society of Chemistry, 2015-03-02)Allenamides participate as two-carbon components in an intermolecular [2 + 2 + 2] cycloaddition with alkenes and aldehydes when treated with catalytic amounts of a phosphite gold complex. The reaction is highly regio- and ... -
Gold(I)-Catalyzed Enantioselective [2+2+2] Cycloadditions: An Expedient Entry to Enantioenriched Tetrahydropyran Scaffolds
(American Chemical Society, 2017-02-22)A straightforward and atom-economical enantioselective approach to highly substituted tetrahydropyrans is reported. The process, which consists of an intermolecular gold-catalyzed [2+2+2] cycloaddition between allenamides, ... -
Gold(I)-Catalyzed Intermolecular Cycloaddition of Allenamides with α,β-Unsaturated Hydrazones: Efficient Access to Highly Substituted Cyclobutanes
(American Chemical Society, 2014-11-19)α,β-Unsaturated N,N-dialkyl hydrazones undergo a mild [2 + 2] cycloaddition to allenamides when treated with a suitable gold catalyst. The method, which represents the first application of N,N-dialkyl hydrazones in gold ... -
Highlights from the 52nd EUCHEM conference on stereochemistry, Bürgenstock, Switzerland, May 2017
(Royal Society of Chemistry, 2017-08-24)The strong wind that was blowing in Brunnen on the 4th of May 2017 was prophetic of the storm of ideas and creativity that would later fall over the participants of the 52nd edition of the Bürgenstock conference. The ... -
Hydrazone-modulated peptides for efficient gene transfection
(Royal Society of Chemistry, 2017-02-22)Gene transfection continues to be a major challenge in chemistry, biology and materials sciences. New methodologies and recent breakthroughs have renewed the interest in the discovery and development of new tools for ... -
In situ functionalized polymers for siRNA delivery
(WILEY-VCH Verlag GmbH, 2016-04-21)A new method is reported herein for screening the biological activity of functional polymers across a consistent degree of polymerization and in situ, that is, under aqueous conditions and without purification/isolation ... -
Inhibition of Shikimate Kinase and Type II Dehydroquinase for Antibiotic Discovery: Structure-Based Design and Simulation Studies
(Bentham Science, 2016)The loss of effectiveness of current antibiotics caused by the development of drug resistance has become a severe threat to public health. Current widely used antibiotics are surprisingly targeted at a few bacterial functions ...