排序方式: 共有35条查询结果,搜索用时 15 毫秒
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A Randazzo G Bifulco C Giannini M Bucci C Debitus G Cirino L Gomez-Paloma 《Journal of the American Chemical Society》2001,123(44):10870-10876
Two new metabolites, named halipeptins A and B, have been isolated from the marine sponge Haliclona sp. Their structures were determined by extensive use of one- and two-dimensional NMR experiments, mass spectrometry, and UV and IR spectroscopy. Halipeptin A is a novel 17-membered cyclic depsipeptide, consisting of five residues including two alanines (with L stereochemistry) and three new residues that appear to be previously undescribed from natural sources: 1,2-oxazetidine-4-methyl-4-carboxylic acid, 3-hydroxy-2,2,4-trimethyl-7-methoxydecanoic acid (HTMMD), and N-methyl-delta-hydroxyisoleucine. The HTMMD residue is substituted with 3-hydroxy-2,2,4-trimethyl-7-hydroxydecanoic acid in halipeptin B. Halipeptin A was found to possess very potent anti-inflammatory activity in vivo, causing about 60% inhibition of edema in mice at the dose of 300 microg/kg (i.p.). 相似文献
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Esposito V Virgilio A Randazzo A Galeone A Mayol L 《Chemical communications (Cambridge, England)》2005,(31):3953-3955
Unprecedented DNA quadruplex structures containing a 3'-3' or 5'-5' inversion of polarity site in the G-tract are presented; the quadruplexes are characterized by different elements of symmetry and glycosidic angle conformations. 相似文献
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Chirality Enhancement of Porphyrin Supramolecular Assembly Driven by a Template Preorganization Effect 下载免费PDF全文
Dr. Massimiliano Gaeta Dr. Domenica Raciti Dr. Rosalba Randazzo Dr. Chiara M. A. Gangemi Prof. Antonio Raudino Dr. Alessandro D'Urso Prof. Maria E. Fragalà Prof. Roberto Purrello 《Angewandte Chemie (International ed. in English)》2018,57(33):10656-10660
Cationic polylysine promotes, under neutral conditions, the spontaneous aggregation of opposite charged ZnTPPS in water. Spectroscopic investigations evidence a different preorganization of ZnTPPS onto the polypeptide matrix depending on the chain length. Spinodal decomposition theory in confined geometry is used to model this mechanism by considering the time evolution of a homogeneous distribution of randomly adsorbed particles (porphyrins) onto a rodlike polyelectrolyte (polymer) of variable length L. 相似文献
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Petraccone L Pagano B Esposito V Randazzo A Piccialli G Barone G Mattia CA Giancola C 《Journal of the American Chemical Society》2005,127(46):16215-16223
PNA-DNA chimeras present the interesting properties of PNA, such as the high binding affinity to complementary single-strand (DNA or RNA), and the resistance to nuclease and protease degradation. At the same time, the limitations of an oligomer containing all PNA residues, such as low water solubility, self-aggregation, and low cellular uptake, are effectively overcome. Further, PNA-DNA chimeras possess interesting biological properties as antisense agents. We have explored the ability of PNA-DNA chimeric strands to assemble in quadruplex structures. The rate constant for association of the quadruplexes and their thermodynamic properties have been determined by CD spectroscopy and differential scanning calorimetry (DSC). Thermal denaturation experiments indicated higher thermal and thermodynamic stabilities for chimeric quadruplexes in comparison with the corresponding unmodified DNA quadruplex. Singular value decomposition analysis (SVD) suggests the presence of kinetically stable intermediate species in the quadruplex formation process. The experimental results have been discussed on the basis of molecular dynamic simulations. The ability of PNA-DNA chimeras to form stable quadruplex structures expands their potential utility as therapeutic agents. 相似文献
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A. Tumino M. Lattuada S. Romano C. Spitaleri D. Vinciguerra Z. Basrak O.Yu. Goryunov V.V. Ostashko S. Szilner P. Figuera D. Lo Presti C. Petta N. Randazzo S. Reito G.V. Russo S. Tudisco 《The European Physical Journal A - Hadrons and Nuclei》2001,12(3):327-334
High-spin states of 24Mg produced in the 16O + 12C interaction and decaying into the 16Og.s. + 8Beg.s. channel have been observed in the excitation region between 35 and 52 MeV. Spins have been assigned on the basis of the analysis
of the measured angular correlations. Some of these states with positive parity correspond to the known resonances of the
12C( 12C, 8Beg.s.) 16O reaction belonging to the 16O-2α rotational band of 24Mg. Moreover other resonances show up at higher excitation energy with an energy-spin relationship again suggesting a 16O-2α cluster structure for the associated configuration.
Received: 6 July 2001 / Accepted: 16 October 2001 相似文献
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Dr. Massimiliano Gaeta Dr. Giuseppe Sortino Dr. Rosalba Randazzo Dr. Ilenia Pisagatti Prof. Anna Notti Prof. Maria Elena Fragalà Prof. Melchiorre F. Parisi Prof. Alessandro D'Urso Prof. Roberto Purrello 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3515-3518
The hierarchical assembly, in aqueous solution, of a new multi-metalloporphyrin/calixarene aggregate has been accomplished. In this supramolecular system transfer of chirality, from the outermost components to the central porphyrin reporter, takes place as a result of favorable and fully noncovalent long-range electronic communication. 相似文献
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F. Amorini V. Sipala G. Cardella L. Auditore C. Boiano B. Carbone A. Di Pietro G. Fallica P. Figuera P. Finocchiaro L. Grassi E. La Guidara P. Guazzoni I. Lombardo D. Loria A. Pappalardo A. Piazza S. Pirrone N. Randazzo F. Rizzo L. Zetta 《Nuclear Physics B - Proceedings Supplements》2009,173(1):194-197
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