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161.
Multitarget Drug Discovery for Alzheimer's Disease: Triazinones as BACE‐1 and GSK‐3β Inhibitors
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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
162.
Identification of Structure–Activity Relationships from Screening a Structurally Compact DNA‐Encoded Chemical Library
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Dr. Raphael M. Franzini Dr. Torun Ekblad Dr. Nan Zhong Moreno Wichert Willy Decurtins Angela Nauer Mauro Zimmermann Dr. Florent Samain Dr. Jörg Scheuermann Dr. Peter J. Brown Prof. Dr. Jonathan Hall Dr. Susanne Gräslund Prof. Dr. Herwig Schüler Prof. Dr. Dario Neri 《Angewandte Chemie (International ed. in English)》2015,54(13):3927-3931
Methods for the rapid and inexpensive discovery of hit compounds are essential for pharmaceutical research and DNA‐encoded chemical libraries represent promising tools for this purpose. We here report on the design and synthesis of DAL‐100K, a DNA‐encoded chemical library containing 103 200 structurally compact compounds. Affinity screening experiments and DNA‐sequencing analysis provided ligands with nanomolar affinities to several proteins, including prostate‐specific membrane antigen and tankyrase 1. Correlations of sequence counts with binding affinities and potencies of enzyme inhibition were observed and enabled the identification of structural features critical for activity. These results indicate that libraries of this type represent a useful source of small‐molecule binders for target proteins of pharmaceutical interest and information on structural features important for binding. 相似文献
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165.
Graphene Oxide Nanosheets Modified with Single‐Domain Antibodies for Rapid and Efficient Capture of Cells
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Dr. Christopher S. Theile Neelkanth M. Bardhan Dr. Priyank V. Kumar Joao N. Duarte Dr. Takeshi Maruyama Ali Rashidfarrokh Dr. Angela M. Belcher Dr. Hidde L. Ploegh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17178-17183
Peripheral blood can provide valuable information on an individual’s immune status. Cell‐based assays typically target leukocytes and their products. Characterization of leukocytes from whole blood requires their separation from the far more numerous red blood cells. 1 Current methods to classify leukocytes, such as recovery on antibody‐coated beads or fluorescence‐activated cell sorting require long sample preparation times and relatively large sample volumes. 2 A simple method that enables the characterization of cells from a small peripheral whole blood sample could overcome limitations of current analytical techniques. We describe the development of a simple graphene oxide surface coated with single‐domain antibody fragments. This format allows quick and efficient capture of distinct WBC subpopulations from small samples (~30 μL) of whole blood in a geometry that does not require any specialized equipment such as cell sorters or microfluidic devices. 相似文献
166.
Robbert van Putten Evgeny A. Uslamin Marcel Garbe Chong Liu Dr. Angela Gonzalez-de-Castro Dr. Martin Lutz Dr. Kathrin Junge Prof. Dr. Emiel J. M. Hensen Prof. Dr. Matthias Beller Dr. Laurent Lefort Prof. Dr. Evgeny A. Pidko 《Angewandte Chemie (International ed. in English)》2017,56(26):7531-7534
Catalytic hydrogenation of carboxylic acid esters is essential for the green production of pharmaceuticals, fragrances, and fine chemicals. Herein, we report the efficient hydrogenation of esters with manganese catalysts based on simple bidentate aminophosphine ligands. Monoligated Mn PN complexes are particularly active for the conversion of esters into the corresponding alcohols at Mn concentrations as low as 0.2 mol % in the presence of sub-stoichiometric amounts of KOtBu base. 相似文献
167.
We define a new statistic on the even hyperoctahedral groups which is a natural analogue of the odd length statistic recently defined and studied on Coxeter groups of types and . We compute the signed (by length) generating function of this statistic over the whole group and over its maximal and some other quotients and show that it always factors nicely. We also present some conjectures. 相似文献
168.
The aims of this note is to present a new model based on a new representation of the curvature energy in the indeterminate couple stress model and to discuss some related choices from the literature. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
169.
Sircar S Wu H Li J Lueking AD 《Langmuir : the ACS journal of surfaces and colloids》2011,27(23):14169-14179
The intriguing hysteretic adsorption-desorption behavior of certain microporous metal-organic frameworks (MMOFs) has received considerable attention and is often associated with a gate-opening (GO) effect. Here, the hysteretic adsorption of N(2) and Ar to Zn(2)(bpdc)(2)(bpee) (bpdc = 4,4'-biphenyldicarboxylate; bpee = 1,2-bipyridylethene) shows a pronounced effect of allowed experimental time at 77 and 87 K. When the time allowed is on the order of minutes for N(2) at 77 K, no adsorption is observed, whereas times in excess of 60 h is required to achieve appreciable adsorption up to a limiting total coverage. Given sufficient time, the total uptake for N(2) and Ar converged at similar reduced temperatures, but the adsorption of Ar was significantly more rapid than that of N(2), an observation that can be described by activated configurational diffusion. N(2) and Ar both exhibited discontinuous stepped adsorption isotherms with significant hysteresis, features that were dependent upon the allowed time. The uptake of H(2) at 77 K was greater than for both N(2) and Ar but showed no discontinuity in the isotherm, and hysteretic effects were much less pronounced. N(2) and Ar adsorption data can be described by an activated diffusion process, with characteristic times leading to activation energies of 6.7 and 12 kJ/mol. Fits of H(2) adsorption data led to activation energies in the range 2-7 kJ/mol at low coverage and nonactivated diffusion at higher coverage. An alternate concentration-dependent diffusion model is presented to describe the stepwise adsorption behavior, which is observed for N(2) and Ar but not for H(2). Equilibrium is approached very slowly for adsorption to molecularly sized pores at low temperature, and structural change (gate opening), although it may occur, is not required to explain the observations. 相似文献
170.
Giotta L Mastrogiacomo D Italiano F Milano F Agostiano A Nagy K Valli L Trotta M 《Langmuir : the ACS journal of surfaces and colloids》2011,27(7):3762-3773
The ability of microorganisms to adhere to abiotic surfaces and the potentialities of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy have been exploited to study protonation and heavy metal binding events onto bacterial surfaces. This work represents the first attempt to apply on bacteria the recently developed method known as perfusion-induced ATR-FTIR difference spectroscopy. Such a technique allows measurement of even slight changes in the infrared spectrum of the sample, deposited as a thin layer on an ATR crystal, while an aqueous solution is perfused over its surface. Solutions at different pH have been used for inducing protonation/deprotonation of functional groups lying on the surface of Rhodobacter sphaeroides cells, chosen as a model system. The interaction of Ni(2+) with surface protonable groups of this microorganism has been investigated with a double-difference approach exploiting competition between nickel cations and protons. Protonation-induced difference spectra of simple model compounds have been acquired to guide band assignment in bacterial spectra, thus allowing identification of major components involved in proton uptake and metal binding. The data collected reveal that carboxylate moieties on the bacterial surface of R. sphaeroides play a role in extracellular biosorption of Ni(2+), establishing with this ion relatively weak coordinative bonds. 相似文献