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21.
José Luis García Ruano Ana M. Martín-Castro Francisco Tato M. Giovanna Tocco Saverio Florio Vito Capriati 《Tetrahedron》2010,66(8):1581-1585
The influence of the sulfinyl group as a chiral auxiliary in the stereoselective addition of oxiranyllithiums to (S)-2-p-tolylsulfinylbenzaldehyde has been studied. All reactions evolve with retention of configuration at the starting lithiated carbon. Completely stereoselective additions have been observed when configurations at sulfur and the lithiated carbon are different (matched pair), whereas variable dr's values (ranging between 52:48 and >99:<1%) when they are identical (mismatched pair). 相似文献
22.
Stable Peptides Instead of Stapled Peptides: Highly Potent αvβ6‐Selective Integrin Ligands 下载免费PDF全文
Dr. Oleg V. Maltsev Dr. Udaya Kiran Marelli Tobias G. Kapp Dr. Francesco Saverio Di Leva Dr. Salvatore Di Maro Dr. Markus Nieberler Prof. Dr. Ute Reuning Prof. Dr. Markus Schwaiger Prof. Dr. Ettore Novellino Prof. Dr. Luciana Marinelli Prof. Dr. Horst Kessler 《Angewandte Chemie (International ed. in English)》2016,55(4):1535-1539
The αvβ6 integrin binds the RGD‐containing peptide of the foot and mouth disease virus with high selectivity. In this study, the long binding helix of this ligand was downsized to an enzymatically stable cyclic peptide endowed with sub‐nanomolar binding affinity toward the αvβ6 receptor and remarkable selectivity against other integrins. Computational studies were performed to disclose the molecular bases underlying the high binding affinity and receptor subtype selectivity of this peptide. Finally, the utility of the ligand for use in biomedical studies was also demonstrated here. 相似文献
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24.
Matteo Scampicchio Nathan S. Lawrence Alessandra Arecchi Stella Cosio Saverio Mannino 《Electroanalysis》2007,19(1):85-90
Cyclic voltammetry has been applied to the rapid measurement of free SH‐compounds in food flours samples. The protocol is based on the electrochemical adaptation of the Ellman's test, where the DTNB reacts with SH‐compounds present in food flour extracts, resulting in the equimolar production of the electroactive compound TNBA which, in turns, reacts with phenylendiamine. The reaction is found to provide an analytical signal from which to quantify indirectly free sulfhydryl compounds in flours extracts. 相似文献
25.
Accurate computer simulations of the rotational dynamics of linear molecules solvated in He clusters indicate that the large-size (nanodroplet) regime is attained quickly for light rotors (HCN) and slowly for heavy ones (OCS, N2O, and CO2), thus challenging previously reported results. Those results spurred the view that the different behavior of light rotors with respect to heavy ones-including a smaller reduction of inertia upon solvation of the former-would result from the lack of adiabatic following of the He density upon molecular rotation. We have performed computer experiments in which the rotational dynamics of OCS and HCN molecules was simulated using a fictitious inertia appropriate to the other molecule. These experiments indicate that the approach to the nanodroplet regime, as well as the reduction of the molecular inertia upon solvation, is determined by the anistropy of the potential, more than by the molecular weight. Our findings are in agreement with recent infrared and/or microwave experimental data which, however, are not yet totally conclusive by themselves. 相似文献
26.
A new high-performance liquid chromatographic/electrospray ionization tandem mass spectrometric (HPLC/ESI-MS/MS) method was developed for the simultaneous quantification of 5-fluorouracil (5FU), methotrexate (MTX) and cyclophosphamide (CP) in environmental samples. These compounds, commonly used in the treatment of cancer, are recognized as genotoxic. In order to estimate the occupational exposure of hospital personnel handling these drugs, wipe samples were taken from the working surfaces and directly analyzed (with trophosphamide as internal standard) using a reversed-phase capillary column and MS/MS detection. This is the first HPLC/MS/MS method for the simultaneous determination of 5FU, MTX and CP. The present method offers high sensitivity, with detection limits of 1.1 microg l(-1) for MTX and CP and 33.3 microg l(-1) for 5FU, avoiding any sample preconcentration procedure. Rapidity, specificity, high accuracy (mean values between 92.4 and 99.9%) and precision (mean RSD values between 3.4 and 12.1%) make the method suitable for the routine determination of these three antineoplastic drugs. 相似文献
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A market is considered where trading can take place only at discrete time points, the trading frequency cannot grow without bound, and the number of states of nature is finite. The main objectives of the paper are to show that the market can be completed also with highly correlated risky assets, and to describe an efficient algorithm to compute a self-financing hedging strategy. The algorithm consists off-line of a backwards recursion and on-line of the solution, in each period, of a system of linear equations; it is a consequence of a proof where, using a well-known mathematical property, it is shown that uniqueness of the martingale measure implies completeness also in our setting. The significance of ‘multistate’ models versus the familiar binomial model is discussed and it is shown how the evolution of prices of the (correlated) risky assets can be chosen so that a given probability measure is already the unique equivalent martingale measure. 相似文献
29.
The study of pairs of modules (over a Dedekind domain) arises from two different perspectives, as a starting step in the analysis
of tuples of submodules of a given module, or also as a particular case in the analysis of Abelian structures made by two
modules and a morphism between them. We discuss how these two perspectives converge to pairs of modules, and we follow the
latter one to obtain an alternative approach to the classification of pairs of torsionfree objects. Then we restrict our attention
to pairs of free modules. Our main results are that the theory of pairs of free Abelian groups is co-recursively enumerable,
and that a few remarkable extensions of this theory are decidable.
Work performed under the auspices of GNSAGA-INDAM 相似文献
30.
Renzo LuisiVito Capriati Claudia CarlucciLeonardo Degennaro Saverio Florio 《Tetrahedron》2003,59(49):9707-9712
The α-lithiation reaction of optically active oxazolinyloxiranes has been investigated. The trapping reaction with D2O, MeI and acetone affording substituted oxazolinyloxiranes proved that the corresponding lithiated species are configurationally unstable. A stereoconvergency was observed in the case of lithiation-deuteration sequence of two oxazolinyloxiranes. 相似文献