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31.
Multitarget Drug Discovery for Alzheimer's Disease: Triazinones as BACE‐1 and GSK‐3β Inhibitors 下载免费PDF全文
Federica Prati Dr. Angela De Simone Dr. Paola Bisignano Dr. Andrea Armirotti Dr. Maria Summa Dr. Daniela Pizzirani Dr. Rita Scarpelli Dr. Daniel I. Perez Prof. Dr. Vincenza Andrisano Dr. Ana Perez‐Castillo Prof. Dr. Barbara Monti Francesca Massenzio Dr. Letizia Polito Prof. Dr. Marco Racchi Dr. Angelo D. Favia Dr. Giovanni Bottegoni Prof. Dr. Ana Martinez Prof. Dr. Maria Laura Bolognesi Prof. Dr. Andrea Cavalli 《Angewandte Chemie (International ed. in English)》2015,54(5):1578-1582
Cumulative evidence strongly supports that the amyloid and tau hypotheses are not mutually exclusive, but concomitantly contribute to neurodegeneration in Alzheimer′s disease (AD). Thus, the development of multitarget drugs which are involved in both pathways might represent a promising therapeutic strategy. Accordingly, reported here in is the discovery of 6‐amino‐4‐phenyl‐3,4‐dihydro‐1,3,5‐triazin‐2(1H)‐ones as the first class of molecules able to simultaneously modulate BACE‐1 and GSK‐3β. Notably, one triazinone showed well‐balanced in vitro potencies against the two enzymes (IC50 of (18.03±0.01) μM and (14.67±0.78) μM for BACE‐1 and GSK‐3β, respectively). In cell‐based assays, it displayed effective neuroprotective and neurogenic activities and no neurotoxicity. It also showed good brain permeability in a preliminary pharmacokinetic assessment in mice. Overall, triazinones might represent a promising starting point towards high quality lead compounds with an AD‐modifying potential. 相似文献
32.
Organocatalytic,Asymmetric Eliminative [4+2] Cycloaddition of Allylidene Malononitriles with Enals: Rapid Entry to Cyclohexadiene‐Embedding Linear and Angular Polycycles 下载免费PDF全文
Dr. Nicoletta Brindani Dr. Gloria Rassu Dr. Luca Dell'Amico Dr. Vincenzo Zambrano Dr. Luigi Pinna Dr. Claudio Curti Dr. Andrea Sartori Prof. Dr. Lucia Battistini Prof. Dr. Giovanni Casiraghi Prof. Dr. Giorgio Pelosi Dr. Daniela Greco Prof. Dr. Franca Zanardi 《Angewandte Chemie (International ed. in English)》2015,54(25):7386-7390
A direct aminocatalytic synthesis has been developed for the chemo‐, regio‐, diastereo‐, and enantioselective construction of densely substituted polycyclic carbaldehydes containing fused cyclohexadiene rings. The chemistry utilizes, for the first time, remotely enolizable π‐extended allylidenemalononitriles as electron‐rich 1,3‐diene precursors in a direct eliminative [4+2] cycloaddition with both aromatic and aliphatic α,β‐unsaturated aldehydes. The generality of the process is demonstrated by approaching 6,6‐, 5,6‐, 7,6‐, 6,6,6‐, and 6,5,6‐fused ring systems, as well as biorelevant steroid‐like 6,6,6,6,5‐ and 6,6,6,5,6‐rings. A stepwise reaction mechanism for the key [4+2] addition is proposed as a domino bis‐vinylogous Michael/Michael/retro‐Michael reaction cascade. The utility of the malononitrile moiety as traceless activating group of the dicyano nucleophilic substrates is demonstrated. 相似文献
33.
Reinhard Farwig Giovanni P. Galdi Hermann Sohr 《Journal of Mathematical Fluid Mechanics》2006,8(3):423-444
We investigate a class of weak solutions, the so-called very weak solutions, to stationary and nonstationary Navier–Stokes equations in a bounded domain
. This notion was introduced by Amann [3], [4] for the nonstationary case with nonhomogeneous boundary data leading to a very
large solution class of low regularity. Here we are mainly interested in the investigation of the “largest possible” class
of solutions u for the more general problem with arbitrary divergence k = div u, boundary data g = u|∂Ω and an external force f, as weak as possible, but maintaining uniqueness. In principle, we will follow Amann’s approach. 相似文献
34.
Summary We study a stationary, nonlinear, particle transport problem in slab geometry with general boundary conditions. The existence and uniqueness of the solution is proved by means of fixed point techniques, provided that the source term is sufficiently small.
Sommario Si studia un problema stazionario nonlineare di particelle in geometria piana con condizioni al contorno generali. L'esistenza e unicitá della soluzione è dimostrata con tecniche di punto fisso purchè il termine di sorgente sia sufficientemente piccolo.相似文献
35.
36.
We study the existence of strong solutions to the three-dimensional Navier-Stokes initial-boundary value problem in the domain, , exterior to a rigid body that rotates with constant angular velocity, . We show that when the initial data, u0, are prescribed in an appropriate functional class, a strong solution exists at least in some finite time interval. Moreover, the solution exists for all times, provided u0, in suitable norm, and the magnitude of do not exceed a certain constant depending only on the kinematic viscosity and on the regularity of . In this latter case, we also show that the velocity field converges to the velocity field of the corresponding steady-state solution. 相似文献
37.
Summary In this work, we are concerned with the stationary neutron transport Boltzmann equation (in its integral form) in a parallelepiped. Functional methods allow us to prove that the integral transport operator, which is defined in L2 space, has eigenvalues depending continuously and monotonically on geometrical and physical parameters. We show that the eigenfunctions are continuous with respect to set of the spatial variables and the optical parameters. Finally, we remark that the same results are valid if the study is carried out in the Banach space C.
Work performed under contract C.N.R. (Gruppo Nazionale per la Fisica Matematica). 相似文献
Sommario In questo lavoro consideriamo l'equazione stazionaria di Boltzmann (nella forma integrale) per neutroni monoenergetici nel caso di un sistema tridimensionale a forma di parallelepipedo. L'uso di alcuni metodi dell'analisi funzionale ci permette di provare che l'operatore integrale del trasporto, definito nello spazio L2, ha autovalori che dipendono continuamente dai parametri geometrici e fisici. Si prova che le autofunzioni sono continue rispetto all'insieme delle variabili spaziali e dei parametri ottici. Infine, si osserva che gli stessi risultati sono validi se l'operatore del trasporto agisce nello spazio di Banach C.
Work performed under contract C.N.R. (Gruppo Nazionale per la Fisica Matematica). 相似文献
38.
39.
Giovanni P. Crespi Andreas H. Hamel Carola Schrage 《Journal of Mathematical Analysis and Applications》2015
Extremal problems are studied involving an objective function with values in (order) complete lattices of sets generated by so-called set relations. Contrary to the popular paradigm in vector optimization, the solution concept for such problems, introduced by F. Heyde and A. Löhne, comprises the attainment of the infimum as well as a minimality property. The main result is a Minty type variational inequality for set optimization problems which provides a sufficient optimality condition under lower semicontinuity assumptions and a necessary condition under appropriate generalized convexity assumptions. The variational inequality is based on a new Dini directional derivative for set-valued functions which is defined in terms of a “lattice difference quotient.” A residual operation in a lattice of sets replaces the inverse addition in linear spaces. Relationships to families of scalar problems are pointed out and used for proofs. The appearance of improper scalarizations poses a major difficulty which is dealt with by extending known scalar results such as Diewert's theorem to improper functions. 相似文献
40.
The probability distribution for the effective Majorana mass as a function of the lightest neutrino mass in the standard three neutrino scheme is computed via a random sampling from the distributions of the involved mixing angles and squared mass differences. A flat distribution in the \([0,2\pi ]\) range for the Majorana phases is assumed, and the dependence of small values of the effective mass on the Majorana phases is highlighted. The study is then extended with the addition of the cosmological bound on the sum of the neutrino masses. Finally, the prospects for \(0\nu \beta \beta \) decay search with \(^{76}\)Ge, \(^{130}\)Te and \(^{136}\)Xe are discussed, as well as those for the measurement of the electron neutrino mass. 相似文献