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1.
Gabor Schmera Adi Bulsara David Pierson Frank Moss Enrico Di Cera 《Journal of statistical physics》1993,71(5-6):1179-1190
We consider the class of experiments which can be characterized by a Fokker-PIanck dynamics corresponding to the overdamped motion of a state point in a suitable stochastic potential. We assume that the general form of the potential is known (or can be guessed with reasonable accuracy), but that its parameters are to be determined experimentally by measurements made with a noisy instrument. This possible method for determining the potential parameters, which exploits the system's own internal stochastic motion in order to explore rapidly its available parameter space, is substantially more efficient than traditional methods involving time averages of single point measurements, and yet does not appear to have been previously considered. The method could be important when, for example, the experiment must be completed in a limited time owing either to the expense of the experimental materials or to the temporary stationarity of the preparation, situations which are commonly encountered in experimental biochemistry and biology. 相似文献
2.
Dr. Minqiang Jia Dr. Gianpiero Cera Daniele Perrotta Prof. Magda Monari Prof. Marco Bandini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9875-9878
A careful interplay between the π electrophilicity of a cationic AuI center and the basicity of the corresponding counterion allowed for the chemo‐ and regioselective inter‐ as well as intramolecular de‐aromatization of 2,3‐disubstituted indoles with allenamides. The silver‐free bifunctional Lewis acid/Brønsted base complex [{2,4‐(tBu)2C6H3O}3PAuTFA] assisted the formation of a range of densely functionalized indolenines under mild conditions. 相似文献
3.
Cera G Crispino P Monari M Bandini M 《Chemical communications (Cambridge, England)》2011,47(27):7803-7805
A reliable synthetic route to fused polycyclic indolines is documented by the development of a stereoselective gold catalyzed cascade cyclization of indole propargylic alcohols. 相似文献
4.
Weak O‐Assistance Outcompeting Strong N,N‐Bidentate Directing Groups in Copper‐Catalyzed C−H Chalcogenation
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Dr. Gianpiero Cera Prof. Dr. Lutz Ackermann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8475-8478
A copper‐mediated C?H chalcogenation of triazoles has been achieved by weak coordination. The user‐friendly protocol showed high functional‐group tolerance and ample substrate scope, yielding fully substituted 1,2,3‐triazoles with complete positional site‐selectivity. The C?H selenylation could likewise be achieved by means of copper catalysis. Our findings highlight for the first time that weak O‐coordination can outcompete the strong N,N‐bidentate coordination mode in C?H functionalization technology. 相似文献
5.
Di Cera E Page MJ Bah A Bush-Pelc LA Garvey LC 《Physical chemistry chemical physics : PCCP》2007,9(11):1291-1306
Thrombin is a Na(+)-activated, allosteric serine protease that plays multiple functional roles in blood pathophysiology. Binding of Na(+) is the major driving force behind the procoagulant, prothrombotic and signaling functions of the enzyme. This review summarizes our current understanding of the molecular basis of thrombin allostery with special emphasis on the kinetic aspects of Na(+) activation. The molecular mechanism of thrombin allostery is a remarkable example of long-range communication that offers a paradigm for many other biological systems. 相似文献
6.
Expedient Iron‐Catalyzed C−H Allylation/Alkylation by Triazole Assistance with Ample Scope
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Dr. Gianpiero Cera Tobias Haven Prof. Dr. Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2016,55(4):1484-1488
Triazole assistance set the stage for a unified strategy for the iron‐catalyzed C?H allylation of arenes, heteroarenes, and alkenes with ample scope. The versatile catalyst also proved competent for site‐selective methylation, benzylation, and alkylation with challenging primary and secondary halides. Triazole‐assisted C?H activation proceeded chemo‐, site‐, and diastereo‐selectively, and the modular TAM directing group was readily removed in a traceless fashion under exceedingly mild reaction conditions. 相似文献
7.
Dr. Stefan Schoder Dr. Hendrik V. Schröder Dr. Luca Cera Dr. Rakesh Puttreddy Arne Güttler Dr. Ute Resch-Genger Prof. Kari Rissanen Prof. Christoph A. Schalley 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(13):3257-3261
Organic fluorophores, particularly stimuli-responsive molecules, are very interesting for biological and material sciences applications, but frequently limited by aggregation- and rotation-caused photoluminescence quenching. A series of easily accessible bipyridinium fluorophores, whose emission is quenched by a twisted intramolecular charge-transfer (TICT) mechanism, is reported. Encapsulation in a cucurbit[7]uril host gave a 1:1 complex exhibiting a moderate emission increase due to destabilization of the TICT state inside the apolar cucurbituril cavity. A much stronger fluorescence enhancement is observed in 2:2 complexes with the larger cucurbit[8]uril, which is caused by additional conformational restriction of rotations around the aryl/aryl bonds. Because the cucurbituril complexes are pH switchable, this system represents an efficient supramolecular ON/OFF fluorescence switch. 相似文献
8.
Prof. Gianpiero Cera Gabriele Giovanardi Prof. Andrea Secchi Prof. Arturo Arduini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(40):10261-10266
We report the synthesis and characterization of novel triphosphine calix[6]arene ligands. These supramolecular wheels, with recognition features governed by the hydrogen-bonding domain, were employed to synthesize multitasking trinuclear gold(I) complexes as a new platform for the synthesis of interwoven (pseudo)rotaxane species. In parallel, the multivalent, metal-bonded upper rim displayed catalytic features promoting highly selective gold-catalyzed cycloisomerization reactions of 1,6-enynes. 相似文献
9.
E. Di Cera 《Il Nuovo Cimento D》1990,12(1):61-68
Summary A statistical thermodynamic model for ligand binding to giant respiratory macromolecules, such as molluscan hemocyanins, is
proposed. The model complies with the fundamental structural organization of this class of proteins. It assumes that each
morphological unit functions as the element of a one-dimensional Ising lattice, so that conformational transitions occurring
upon ligand binding may be propagated to the whole macromolecule through nearest-neighbour interactions. An application of
the model to the analysis of oxygen equilibria of the β-hemocyanin ofHelix pomatia is presented and its general properties are discussed in connection with other models.
Riassunto Si propone un modello statistico per le interazioni proteina-substrato in sistemi macromolecolari giganti, quali le emocianine di mollusco. Il modello è basato su rilievi strutturali e fornisce un'interpretazione termodinamica dell'arrangiamento ciclico delle subunità morfologiche delle emocianine secondo il modello classico di Ising.
Резюме Предлагается статистическая термодинамическая модель для связи лигандов в гигантских дыхательных макромолекулах, таких как гемоцианин молюсков. Эта модель согласуется со структурной организацией этого класса белков. Предполагается, что каждая морфологическая единица действует, как элемент одномерной решетки Пзинга, так что конформационные переходы, наблюдаемые на связях лигандов, могут распространяться вдоль всей макромолекулы через взаимодействия ближайших соседей. Предлагается применение этой модели к анализу кислородного равновесия для β-гемоцианина. Обсуждоются общие свойства в контексте с другими моделями.相似文献
10.
The synthesis of architecturally complex polycyclic fused indolines is achieved in a chemo-, regio-, and stereodefined manner, via an enantioselective gold-catalyzed cascade hydroindolination/iminium trapping synthetic sequence. Highly functionalized tetracyclic fused furoindolines (2) and dihydropyranylindolines (4) are synthesized in moderate to good yields and enantiomeric excesses of up to 87%. 相似文献