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991.
Structural Modifications of cis‐Glycofused Benzopyran Compounds and Their Influence on the Binding to Amyloid‐β Peptide 下载免费PDF全文
Dr. Cristina Airoldi Dr. Giuseppe D'Orazio Dr. Barbara Richichi Dr. Cinzia Guzzi Dr. Veronica Baldoneschi Dr. Laura Colombo Dr. Mario Salmona Prof. Cristina Nativi Prof. Francesco Nicotra Prof. Barbara La Ferla 《化学:亚洲杂志》2016,11(2):299-309
A small library of glycofused tricyclic compounds with a central pyran ring chemically modified in the position para to the ring oxygen has been synthesised. The influence of the chemical modification on the structural conformation of the compounds and on their ability to bind Aβ peptide has been evaluated respectively using molecular mechanics (MM) and molecular dynamics (MD) simulations, and STD NMR spectroscopy. The introduction of particularly polar/charged groups leads to the loss of binding ability, without a significant change in the conformation, whilst other substitutions does not significantly affect either the structural conformation or the binding. 相似文献
992.
Silvia G. Prolongo M. Burón A. Salazar A. Ureña J. Rodríguez 《Journal of Thermal Analysis and Calorimetry》2007,87(1):269-276
Blends based on epoxy resins and a random copolymer, poly(styrene-co-allylalcohol)
(PS-co-PA) were studied, analysing the effect of epoxy nature. The epoxy cross-linking
reaction was carried out by homopolymerisation, using an imidazole as initiator,
and by addition of several amine hardeners. The imidazole acts as initiator
of anionic epoxy etherification and as catalyser of epoxy-hydroxyl reaction.
Important differences were observed on the network structure and phase behaviour
of blends depending on the nature of epoxy matrix. These cause that the blends
present different morphologies and different dynamic mechanical properties. 相似文献
993.
Marco Radi Vincenzo Bernardo Giulia Vignaroli Annalaura Brai Mariangela Biava Silvia Schenone Maurizio Botta 《Tetrahedron letters》2013
A versatile approach for the synthesis of 1,4-disubstituted pyrazolo[3,4-d]pyrimidines has been developed. Starting from commercially available allopurinol, TBAF mediated N1-functionalization and subsequent C4 nucleophilic substitution, under microwave assisted- or standard heating conditions, granted access to highly functionalized pyrazolo[3,4-d]pyrimidines of potential biological interest. 相似文献
994.
Dan Donescu Liana Fusulan Cristian Petcu Marilena Vasilescu Calin Deleanu Silvia Udrea 《Macromolecular Symposia》2002,179(1):315-330
The microemulsion system containing vinyl acetate (Vac), silane derivatives tetraethoxysilane (TEOS), methacryloxypropyltrimethoxysilane (MPTS), vinyltriethoxysilane (VTES), methyltriethoxysilane (MeTES), octyltriethoxysilane (OTES), nonylphenol etoxylated with 25 mol of ethylene oxyde (NPEO25) and water was studied. It was established that the probability of microemulsion formation increases with surfactant concentration. The microenviroment of the solubilization of the VAc and of silane derivatives in the aggregates of NPEO25 was affected by their polarity. Hybrid materials were obtained by sol-gel reaction of silane derivatives combined with free-radical polymerization of VAc. The change of the glass transition temperature and of thermal stability of the polymer chains in the presence of the inorganic one proved the formation of simultaneous polymer inorganic hybrids. 相似文献
995.
996.
997.
The Skill Vehicle Routing Problem (Skill VRP) considers vehicle routing under the assumption of skill requirements given on demand nodes. These requirements have to be met by the serving vehicles. No further constraints, like capacity or cost restrictions, are imposed. Skill VRP solutions may show a tendency to have a bad load balancing and resource utilization. In a majority of solutions only a subset of vehicles is active. Moreover, a considerable share of demand nodes is served by vehicles that have a skill higher than necessary. A reason for that solution behavior lies in the model itself. As no resource restrictions are imposed, the Skill VRP tends to produce TSP-like solutions. To obtain better balanced solutions, we introduce two new approaches. First we propose a minmax model that aims at minimizing the maximal vehicle tour length. Second we suggest a two-step method combining the minmax approach with a distance constrained model. Our experiments illustrate that these approaches lead to improvements in load balancing and resource utilization, but, with different impact on routing costs. 相似文献
998.
999.
Luca Giulio Cristina Padula Silvia Pescina Sara Nicoli Patrizia Santi 《Biomedical chromatography : BMC》2022,36(5):e5349
An innovative and sensitive HPLC–UV method for the extraction and quantification of methotrexate (MTX) in skin layers was developed and validated. Owing to the physico-chemical characteristics of the drug and the nature of the tissue, it was necessary to use folic acid (FA) as an internal standard for MTX quantification in the dermis. MTX (and FA) analysis was performed on a Phenomenex Jupiter C18 column, using a 50 mm sodium acetate buffer (pH 3.6) and methanol mixture (87:13, v/v) as mobile phase, pumped at 1 ml/min. The absorbance was monitored at 290 nm. The method was selective, linear in the range 0.11–8.49 μg/ml for extraction solvent and 0.05–8.94 μg/ml for pH 7.4 phosphate-buffered saline, precise and accurate, with lower limits of quantitation of 0.11 μg/ml (extraction solvent) and 0.05 μg/ml (pH 7.4 phosphate-buffered saline). The method developed is suitable for the quantification of MTX in skin layers at the end of in vitro permeation experiments; the overall mass balance was 96.5 ± 1.4%, in line with the requirements of the Organisation for Economic Co-operation and Development guideline for the testing of the chemicals (Skin absorption: in vitro method). 相似文献
1000.
Dr. Fariba Saadati Silvia Cammarone Prof. Dr. Marco A. Ciufolini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(48):e202200906
This paper describes a synthesis of ALC-0315 by a sequence that more than doubles the overall yield relative to the published one, and that employs much cleaner reactions, thereby facilitating purifications to a considerable extent 相似文献