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211.
212.
Direct On‐Surface Patterning of a Crystalline Laminar Covalent Organic Framework Synthesized at Room Temperature
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Alejandro de la Peña Ruigómez David Rodríguez‐San‐Miguel Dr. Kyriakos C. Stylianou Dr. Massimiliano Cavallini Dr. Denis Gentili Dr. Fabiola Liscio Prof. Silvia Milita Dr. Otello Maria Roscioni Dr. Maria Luisa Ruiz‐González Carlos Carbonell Prof. Daniel Maspoch Dr. Rubén Mas‐Ballesté Dr. José Luis Segura Dr. Félix Zamora 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10666-10670
We report herein an efficient, fast, and simple synthesis of an imine‐based covalent organic framework (COF) at room temperature (hereafter, RT‐COF‐1 ). RT‐COF‐1 shows a layered hexagonal structure exhibiting channels, is robust, and is porous to N2 and CO2. The room‐temperature synthesis has enabled us to fabricate and position low‐cost micro‐ and submicropatterns of RT‐COF‐1 on several surfaces, including solid SiO2 substrates and flexible acetate paper, by using lithographically controlled wetting and conventional ink‐jet printing. 相似文献
213.
Asymmetric Synthesis of Fluorinated Isoindolinones through Palladium‐Catalyzed Carbonylative Amination of Enantioenriched Benzylic Carbamates
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Dr. Pablo Barrio Ignacio Ibáñez Lidia Herrera Dr. Raquel Román Dr. Silvia Catalán Prof. Dr. Santos Fustero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11579-11584
The asymmetric synthesis of fluorinated isoindolinones has been achieved by a palladium‐catalyzed aminocarbonylation reaction of the corresponding α‐fluoroalkyl o‐iodobenzylamines. A base‐mediated anti β‐hydride elimination process was suggested to explain the partial erosion of the optical purity observed in some cases. This mechanistic rationale enabled the minimization of this partial racemization by fine‐tuning the pKa of the base. 相似文献
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Taucher SC 《Community genetics》2004,7(2-3):121-125
Demographic changes in Chile have positioned congenital malformations as a major cause of infant morbidity and mortality. At the same time, medical genetics has become increasingly important in relation to the diagnosis and management of individuals with birth defects and hereditary conditions as well as in the study of pathological pregnancies and reproductive problems. In addition, recent advances in genomic research are expanding the relevance of medical genetics to medicine as a whole. This article reviews the clinical genetic resources currently available in Chile; the teaching of genetics in undergraduate, graduate, and continued medical education; some relevant interventions that have taken place in our country, e.g. the expansion of the newborn screening program and the initiation of a folic acid fortification program, and recent efforts to enhance population access to clinical genetics services. 相似文献
216.
A regular perturbation analytical‐numerical method for the evolution of precancerous lesions caused by the human papillomavirus
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Silvia Jerez Luz Maria Gonzalez Francisco J. Solis 《Numerical Methods for Partial Differential Equations》2015,31(3):847-855
A numerical method is developed to analyze the behavior of the evolution of the lesions at the cervical cells caused by the human papillomavirus. The model to be solved consists in a one‐dimensional nonlinear advection–diffusion‐reaction equation. Such equation is approximated by a consistent explicit difference scheme which is based on regular perturbation theory. A constructive procedure for the numerical scheme is given and finally an illustrative example of the evolution of a mild dysplasia is included. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 31: 847–855, 2015 相似文献
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Lennartz MC Baumert M Karthäuser S Albrecht M Waser R 《Langmuir : the ACS journal of surfaces and colloids》2011,27(16):10312-10318
One of the challenges in molecular electronics is to design molecules which can be used as functional units in electronic devices. The subject of our investigations is an asymmetrical molecule, dihydroxy(4-thiomorpholinomethyl)benzoic acid (TMBA), whose structural and electronic properties are characterized. The self-assembly behavior of TMBA on Au(111) surfaces resulting in highly ordered monolayers is obtained using scanning tunneling microscopy (STM). Furthermore, investigations on the electronic properties of the combined metal/molecule system reveal an orbital mediated tunneling process and tunneling decay constants for the carboxylic and thiomorpholino group. Thus, a diode-like character of TMBA is shown to be caused by intrinsic electronic properties of different molecular moieties. 相似文献
219.
La Ferla B Airoldi C Zona C Orsato A Cardona F Merlo S Sironi E D'Orazio G Nicotra F 《Natural product reports》2011,28(3):630-648
Cancer is one of the major causes of death worldwide. As a consequence, many different therapeutic approaches, including the use of glycosides as anticancer agents, have been developed. Various glycosylated natural products exhibit high activity against a variety of microbes and human tumors. In this review we classify glycosides according to the nature of their aglycone (non-saccharidic) part. Among them, we describe anthracyclines, aureolic acids, enediyne antibiotics, macrolide and glycopeptides presenting different strengths and mechanisms of action against human cancers. In some cases, the glycosidic residue is crucial for their activity, such as in anthracycline, aureolic acid and enediyne antibiotics; in other cases, Nature has exploited glycosylation to improve solubility or pharmacokinetic properties, as in the glycopeptides. In this review we focus our attention on natural glycoconjugates with anticancer properties. The structure of several of the carbohydrate moieties found in these conjugates and their role are described. The structure–activity relationship of some of these compounds, together with the structural features of their interaction with the biological targets, are also reported. Taken together, all this information is useful for the design of new potential anti-tumor drugs. 相似文献
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