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521.
We derive a bound for the security of quantum key distribution with finite resources under one-way postprocessing, based on a definition of security that is composable and has an operational meaning. While our proof relies on the assumption of collective attacks, unconditional security follows immediately for standard protocols such as Bennett-Brassard 1984 and six-states protocol. For single-qubit implementations of such protocols, we find that the secret key rate becomes positive when at least N approximately 10(5) signals are exchanged and processed. For any other discrete-variable protocol, unconditional security can be obtained using the exponential de Finetti theorem, but the additional overhead leads to very pessimistic estimates. 相似文献
522.
Marianna Tosato Marco Verona Chiara Favaretto Marco Pometti Giordano Zanoni Fabrizio Scopelliti Francesco Paolo Cammarata Luca Morselli Zeynep Talip Nicholas P. van der Meulen Valerio Di Marco Mattia Asti 《Molecules (Basel, Switzerland)》2022,27(13)
Copper radioisotopes are generally employed for cancer imaging and therapy when firmly coordinated via a chelating agent coupled to a tumor-seeking vector. However, the biologically triggered Cu2+-Cu+ redox switching may constrain the in vivo integrity of the resulting complex, leading to demetallation processes. This unsought pathway is expected to be hindered by chelators bearing N, O, and S donors which appropriately complements the borderline-hard and soft nature of Cu2+ and Cu+. In this work, the labelling performances of a series of S-rich polyazamacrocyclic chelators with [64Cu]Cu2+ and the stability of the [64Cu]Cu-complexes thereof were evaluated. Among the chelators considered, the best results were obtained with 1,7-bis [2-(methylsulfanyl)ethyl]-4,10,diacetic acid-1,4,7,10-tetraazacyclododecane (DO2A2S). DO2A2S was labelled at high molar activities in mild reaction conditions, and its [64Cu]Cu2+ complex showed excellent integrity in human serum over 24 h. Biodistribution studies in BALB/c nude mice performed with [64Cu][Cu(DO2A2S)] revealed a behavior similar to other [64Cu]Cu-labelled cyclen derivatives characterized by high liver and kidney uptake, which could either be ascribed to transchelation phenomena or metabolic processing of the intact complex. 相似文献
523.
Valerio Morlacci Tonino Caruso Marco Chiarini Antonio Arcadi Massimiliano Aschi Laura Palombi 《Molecules (Basel, Switzerland)》2022,27(23)
An electrochemical initiated tandem reaction of anilines with 2-formyl benzonitrile has been developed. Thus, unprecedented 3-N-aryl substituted isoindolinones have been conveniently achieved by constant current electrolysis in a divided cell using catalytic amount of electricity and supporting electrolyte and a Pt-cathode as working electrode. The origin of the electrochemical activation as well as the mechanism of the subsequent chemical cascade reactions have been investigated by DFT calculations. 相似文献
524.
Vincenzo Battaglia Dr. Sara Meninno Prof. Dr. Alessandra Lattanzi 《European journal of organic chemistry》2023,26(40):e202301037
A first catalytic preparation of the popular antiplatelet drug (S)-clopidogrel, known with the tradename of Plavix, has been developed in a one-pot and innovative approach. The synthesis can be performed using commercially available ortho-chlorobenzaldehyde, 1-naphthylsulfonyl acetonitrile, tert-butyl hydroperoxide (TBHP), 4,5,6,7-tetrahydrothieno[3,2-c]pyridine and 20 mol % of a quinidine derived organocatalyst in a single solvent. A Knoevenagel/asymmetric epoxidation/domino ring-opening esterification (DROE) sequence enabled to obtain (S)-clopidogrel in 61 % overall yield and 62 % ee. Fine optimization of the reaction conditions proved to be crucial to set up a selective and efficient process. 相似文献
525.
Bernd Wrackmeyer Angelo G. Giumanini Alberto Gambi Giancarlo Verardo Gastone Gilli Valerio Bertolasi 《Heteroatom Chemistry》2002,13(4):366-372
The 1:1 phenylhydrazine–borane adduct, obtained from phenylhydrazine and sodium borohydride in acidic solution, was investigated by IR, NMR spectroscopy, and MS spectrometry. Ab initio MO calculations indicated the isomer in which the boron center is attached to the primary amino group as the more stable. This forecast was confirmed by solution‐state 1H, 11B, 13C, and 15N NMR spectroscopy, in agreement with the molecular structure in the solid state determined by X‐ray analysis. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:366–372, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10049 相似文献
526.
527.
Mattia Failla Giacomo W. Lombardo Paolo Orlando Dr. Daniele Fiorito Elena Bombonato Dr. Paolo Ronchi Prof. Daniele Passarella Dr. Valerio Fasano 《European journal of organic chemistry》2023,26(16):e202300074
Late-Stage Functionalisation (LSF) is an innovative technique that has been successfully applied to the C−H diversification of pharmaceuticals. However, LSF of the pyridine ring in drug-like molecules is often unselective. As a result, a mixture of structurally related products is obtained, thus making the purification tedious and time-consuming. This review shines a light on recent strategies addressing the selectivity issue in the LSF of complex natural products or drugs containing the pyridine moiety. Specifically, we have reviewed the efforts reported both in academia and industries with the hope of providing a guide for the LSF of elaborated pyridines. 相似文献
528.