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131.
Nicola Monti Stefano Zacchini Massimiliano Massi Alejandro Hochkoeppler Loris Giorgini Valentina Fiorini Alessandra Stefan Stefano Stagni 《应用有机金属化学》2020,34(9):e5806
Herein, we describe a new family of tris chelate homoleptic Ru (II) complexes, [Ru(N^N) 3 ] 2+ , where the role of the diimine-type ligands (N^N) was fulfilled by 2-pyridyl (PTZ) or 2-quinolyl tetrazole (QTZ) derivatives decorated with various alkyl substituents at the N-2 position of the tetrazole ring. The new Ru (II) complexes with general formula [Ru (PTZ-R) 3 ] 2+ and [Ru (QTZ-R) 3 ] 2+ , were obtained as mixtures of facial (fac) and meridional (mer) isomers, as suggested by NMR (1H, 13C) experiments, and confirmed in the case of mer-[Ru (QTZ-Me) 3 ] 2+ , by X-ray crystallography. The photophysical behavior of the tetrazole-based [Ru(N^N) 3 ] 2+ type species was investigated by UV–vis absorption spectroscopy, providing trends typical of polypyridyl Ru (II) complexes. The new homoleptic complexes fac/mer- [Ru (PTZ-R) 3 ] 2+ and fac/mer- [Ru (QTZ-R) 3 ] 2+ have been assessed for any eventual antimicrobial activity towards two different bacteria such as Gram-negative Escherichia coli and Gram-positive Deinococcus radiodurans. Whereas being inactive toward E. coli, the response of agar disks diffusion tests suggested that some of the new fac/mer Ru (II) complexes could inhibit the growth of D. radiodurans. This effect was further investigated by determining the growth kinetics in liquid medium of D. radiodurans exposed to the fac/mer- [Ru (PTZ-R) 3 ] 2+ and fac/mer- [Ru (QTZ-R) 3 ] 2+ complexes at different concentrations. The outcome of these experiments highlighted that the turn-on of the growth inhibitory effect took place as the linear hexyl chain was appended to the PTZ or QTZ scaffold, suggesting also how the inhibitory activity appeared more pronouncedly exerted by the facial isomers fac- [Ru (PTZ-Hex) 3 ] 2+ and fac- [Ru (QTZ-Hex) 3 ] 2+ (MIC = ca. 3.0 μg/ml) with respect to the corresponding meridional isomers (MIC = ca. 6.0 μg/ml). 相似文献
132.
133.
Alkenyl and alkynyl isocyanides were synthesised and then reacted, using microwave flash-heating technology, with thiophenol, 2-mercaptoethanol and ethanethiol, in the presence of a radical initiator, to give highly functionalised pyrrolines and pyroglutamates. Direct comparison with results obtained using traditional heating techniques showed the advantage of using the microwave technology in terms of faster reactions and better yields. 相似文献
134.
Paolo Bigini Fabrizio Gardoni Sara Barbera Alfredo Cagnotto Elena Fumagalli Annalisa Longhi Massimiliano M Corsi Monica Di Luca Tiziana Mennini 《BMC neuroscience》2006,7(1):71
Background
The localisation of AMPA and NMDA receptor subunits was studied in a model of degeneration of cervical spinal motoneurons, the wobbler mouse. Cervical regions from early or late symptomatic wobbler mice (4 or 12 weeks of age) were compared to lumbar tracts (unaffected) and to those of healthy mice. 相似文献135.
The ultrafast electron and spin dynamics of Co films was investigated using a femto-second pump-probe technique. The samples were magnetically characterized by means of magnetooptical Kerr effect and non-optical magnetometers, i.e. superconductive quantum interference device and alternating gradient field magnetometer. Time evolution of both, Kerr rotation and ellipticity, was measured at different points of the static hysteresis cycle. This allowed separating magnetic and non-magnetic contributions to the signal. The sample magnetization was found to drop within 200 fs, following the pulse cross-correlation trace, while the magnetization recovery time was found to last few picoseconds. 相似文献
136.
137.
Marco Andreatta Massimiliano Mella 《Transactions of the American Mathematical Society》1997,349(11):4669-4683
A complex manifold of dimension together with an ample vector bundle on it will be called a generalized polarized variety. The adjoint bundle of the pair is the line bundle . We study the positivity (the nefness or ampleness) of the adjoint bundle in the case . If this was previously done in a series of papers by Ye and Zhang, by Fujita, and by Andreatta, Ballico and Wisniewski.
If is nef then, by the Kawamata-Shokurov base point free theorem, it supports a contraction; i.e. a map from onto a normal projective variety with connected fiber and such that , for some ample line bundle on . We describe those contractions for which . We extend this result to the case in which has log terminal singularities. In particular this gives Mukai's conjecture 1 for singular varieties. We consider also the case in which for every fiber and is birational.
138.
Jeremy N. Harvey Massimiliano Aschi Helmut Schwarz Wolfram Koch 《Theoretical chemistry accounts》1998,99(2):95-99
The phenyl cation is known to have two low-energy minima, corresponding to 1
A
1 and 3
B
1 states, the first of which is more stable by ca. 25 kcal/mol. The minimum energy crossing point between these two surfaces,
located at various levels including a hybrid method first described here, lies just above the minimum of the triplet, 0.12
kcal/mol at the CCSD(T)/cc-pVDZ//B3LYP/SV level, and there is significant spin-orbit coupling between the surfaces at this
point. On the basis of these results, the lifetime of the triplet is expected to be very short.
Received: 24 October 1997 / Accepted: 25 November 1997 相似文献
139.
Carla Di Teodoro Massimiliano Aschi Andrea Amadei Danilo Roccatano Francesco Malatesta Luca Ottaviano 《Chemphyschem》2005,6(4):681-689
A theoretical study of the conformational properties of a small heme peptide in aqueous solution is carried out by classical, long-timescale molecular dynamics simulations. The electronic properties of this species, that is, the relative energies of its excited electronic states and the redox potential, are reproduced and related to the conformational behavior using the perturbed matrix method and basic statistical mechanics. Our results show an interesting coupling between the conformational transitions and the electronic properties. These investigations, beyond the biophysically relevant results addressing the long-standing question of the actual role of the enzyme structure on the enzyme activity, are also of some methodological interest since they offer a further computational perspective for including the electronic degrees of freedom into the modeling of rather complex molecular systems. 相似文献
140.
Monica Ermolli Anna Fantozzi Massimiliano Marini Domenico Scotti Branko Balla Sebastian Hoffmann Maddalena Querci Claudia Paoletti Guy Van den Eede 《Accreditation and quality assurance》2006,11(1-2):55-57
GMO protein content in maize flours or fresh crops can be easily assessed by the enzyme-linked immunosorbent assays (ELISA)
and immunochromatographic (lateral flow) strip tests commercially available. Therefore, ELISA can be seen as a useful tool
for screening, for control purposes and for traceability implementation. In order to highlight the importance of monitoring
GMO protein presence in food products and to investigate the performance of representative ELISA commercial kits, we evaluated
three commercial kits by measuring the amount of Cry1Ab/Cry1Ac in IRMM certified reference materials.
Presented at AOAC Europe/Eurachem Symposium March 2005, Brussels, Belgium 相似文献