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101.
Dr. Giampaolo Barone Prof. Dr. José M. Leal Prof. Dr. Fernando Domínguez Dr. Lisandro J. Giovanetti Prof. Dr. Félix G. Requejo Prof. Dr. Begoña García Prof. Dr. M. Arturo López‐Quintela 《Angewandte Chemie (International ed. in English)》2015,54(26):7612-7616
Subnanometric samples, containing exclusively Ag2 and Ag3 clusters, were synthesized for the first time by kinetic control using an electrochemical technique without the use of surfactants or capping agents. By combination of thermodynamic and kinetic measurements and theoretical calculations, we show herein that Ag3 clusters interact with DNA through intercalation, inducing significant structural distortion to the DNA. The lifetime of Ag3 clusters in the intercalated position is two to three orders of magnitude longer than for classical organic intercalators, such as ethidium bromide or proflavine. 相似文献
102.
Dr. Riccardo Bonsignore Sophie R. Thomas Dr. Wim T. Klooster Dr. Simon J. Coles Dr. Robert L. Jenkins Dr. Didier Bourissou Prof. Giampaolo Barone Prof. Angela Casini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4226-4231
With the aim of exploiting new organometallic species for cross-coupling reactions, we report here on the AuIII-mediated Caryl−P bond formation occurring upon reaction of C^N cyclometalated AuIII complexes with phosphines. The [Au(C^N)Cl2] complex 1 featuring the bidentate 2-benzoylpyridine (CCON) scaffold was found to react with PTA (1,3,5-triaza-7-phosphaadamantane) under mild conditions, including in water, to afford the corresponding phosphonium 5 through C−P reductive elimination. A mechanism is proposed for the title reaction based on in situ 31P{1H} NMR and HR-ESI-MS analyses combined with DFT calculations. The C−P coupling has been generalized to other C^N cyclometalated AuIII complexes and other tertiary phosphines. Overall, this work provides new insights into the reactivity of cyclometalated AuIII compounds and establishes initial structure–activity relationships to develop AuIII-mediated C−P cross-coupling reactions. 相似文献
103.
Francesco?FerranteEmail author Giampaolo?Barone Dario?Duca 《Theoretical chemistry accounts》2012,131(3):1165
Potential energy curves of NgH+ cations (Ng = Kr, Xe, Rn) were obtained by using four-component relativistic CCSD(T) coupled cluster calculations. Dissociation
energies, equilibrium bond lengths, electronic properties, such as dipole moments and electric field gradients at the nuclei,
and the related spectroscopic parameters of the electronic ground state have been determined. The results obtained for KrH+ and XeH+ are in good agreement with available experimental data, while those for RnH+ have been determined for the first time at this level of theory. 相似文献
104.
E Mattia A Porta V Merlini G Zanoni G Vidari 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(38):11894-11898
Re catalysis in one-pot reactions: An atom-economical, one-pot strategy that involves alkyne deprotonation and a subsequent rhenium(V)-catalysed Meyer-Schuster rearrangement of the alkynol to provide α,?-unsaturated enones in high yield has been developed. Subsequent in situ hydride reduction or Diels-Alder reaction of the enones provided products in good-to-high overall yields. 相似文献
105.
106.
We present a photorefractive hybrid liquid crystal system that allows strong photorefractive effects on surface plasmon polaritons. We demonstrate its capability to couple energy between two 1.03 eV surface plasmon polariton modes with an efficiency of 25.3±2.3%. We present the energy and grating pitch dependence of the diffraction and a model that can qualitatively explain them. 相似文献
107.
Rebeca Ruiz Begoa García Giuseppe Ruisi Arturo Silvestri Giampaolo Barone 《Journal of Molecular Structure》2009,915(1-3):86-92
The interaction of proflavine (PR) with two B-DNA decamers of alternating AT and GC sequence, called [deca(dG-dC)]2 and [deca(dA-dT)]2, respectively, was computationally investigated by the ONIOM method, exploiting a three-layer QM/QM/MM hybrid approach. The highest level QM method was applied to the model system, which comprises the intercalation site (5th and 6th base pairs) and the inserted PR molecule. The connecting sugar phosphate backbone was added in the medium layer region. Both higher and medium level layers, differing in the size of the basis set used, were treated by the DFT MPWB1K functional. The full system in the lower layer was described by the empirical AMBER force field. The calculated values of the interaction energy of PR with [deca(dG-dC)]2 and [deca(dA-dT)]2, as well as with the dinucleotides d(GpC)2, and d(ApT)2, the latter considered either in vacuo and in the mimicked water solvent, support for a static higher affinity toward G-C compared to the A-T DNA base sequences, in agreement with structural results from crystallographic studies. Furthermore, the different structural characteristics of the [deca(dG-dC)]2/PR complex compared to those of the [deca(dA-dT)]2/PR, furnish a possible interpretation of apparently controversial experimental thermodynamic data, explained in terms of two possible modes of non-covalent binding of ligands with DNA, namely intercalation and external binding, respectively. 相似文献
108.
Buonsante P Giampaolo SM Illuminati F Penna V Vezzani A 《Physical review letters》2008,100(24):240402
We investigate the properties of strongly interacting heteronuclear boson-boson mixtures loaded in realistic optical lattices, with particular emphasis on the physics of interfaces. In particular, we numerically reproduce the recent experimental observation that the addition of a small fraction of 41K induces a significant loss of coherence in 87Rb, providing a simple explanation. We then investigate the robustness against the inhomogeneity typical of realistic experimental realizations of the glassy quantum emulsions recently predicted to occur in strongly interacting boson-boson mixtures on ideal homogeneous lattices. 相似文献
109.
[reaction: see text] A new cellulose-supported reagent for the synthesis of guanidine in aqueous medium is reported starting from commercially available functionalized cellulose beads. Primary and secondary amines, anilines, and amino acids were transformed to the corresponding guanidines in high yields and under very mild conditions. 相似文献
110.
An effective route to chiral optically active 2-substituted benzofurans directly from carboxylic acids is reported. This procedure, which allows the preparation of alpha-alkyl-2-benzofuranmethanamines from N-protected alpha-amino acids without sensible racemization phenomena, proceeds in good yields under mild conditions with the help of microwave irradiation. 相似文献