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41.
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The synthesis of a benzooxazol-5-yl acetic acid derivative (9) with strong heparanase and angiogenesis inhibitory activity, and thus possible commercial interest, is described in detail. 相似文献
43.
Emanuela Fabiola Craparo Girolamo Teresi Maria Chiara Ognibene Maria Pia Casaletto Maria Luisa Bondì Gennara Cavallaro 《Journal of nanoparticle research》2010,12(7):2629-2644
In this article, the synthesis of two amphiphilic polyaspartamide copolymers, useful to obtain polymeric nanoparticles without
using surfactants or stabilizing agents, is described. These copolymers were obtained starting from α,β-poly-(N-2-hydroxyethyl)-dl-aspartamide (PHEA) by following a novel synthetic strategy. In particular, PHEA and its pegylated derivative (PHEA-PEG2000) were functionalized with poly(lactic acid) (PLA) through 1,1′-carbonyldiimidazole (CDI) activation to obtain PHEA–PLA and
PHEA-PEG2000–PLA graft copolymers, respectively. These copolymers were properly purified and characterized by 1H-NMR, FT-IR, and Size Exclusion Chromatography (SEC) analyses, which confirmed that derivatization reactions occurred. Nanoparticles
were obtained from PHEA–PLA and PHEA-PEG2000–PLA graft copolymers by using the high pressure homogenization-solvent evaporation method, avoiding the use of surfactants
or stabilizing agents. Polymeric nanoparticles were characterized by dimensional analysis, before and after freeze-drying
process, and Scanning Electron Microscopy (SEM). Zeta potential measurements and X-ray Photoelectron Spectroscopy (XPS) analysis
demonstrated the presence of PEG and/or PHEA onto the PHEA-PEG2000–PLA and PHEA–PLA nanoparticle surface, respectively. 相似文献
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Luca Nicolotti Chiara CorderoCecilia Cagliero Erica LibertoBarbara Sgorbini Patrizia RubioloCarlo Bicchi 《Analytica chimica acta》2013
The study proposes an investigation strategy that simultaneously provides detailed profiling and quantitative fingerprinting of food volatiles, through a “comprehensive” analytical platform that includes sample preparation by Headspace Solid Phase Microextraction (HS-SPME), separation by two-dimensional comprehensive gas chromatography coupled with mass spectrometry detection (GC × GC–MS) and data processing using advanced fingerprinting approaches. 相似文献
47.
The coupling reaction of allylic halides with diffferent organometallic reagents has been widely utilized for synthetic purpose.1 Unfortunately, with the exception of primary halides which give mostly α attack and of hindered substrates which prefer γ attack, the lack of regioselectivity is a great handicap for the generalization of the method. 相似文献
48.
Jean M. J. Tronchet Fabienne De Villedon De Naide Alessandra Ricca Istvan Komaromi Françise Barbalat-Rey Michel Geoffroy 《Journal of carbohydrate chemistry》2013,32(4-5):537-556
Abstract A series of 3-(N-arylmethyl-N-hydroxyamino)-l,2-O-cyclopentylidene-3-deoxy-5-O-toluoyl-α-D-riboses has been prepared. The blocking groups used were chosen to allow an easy nucleosidation of these compounds to spin labelled analogs of natural nucleosides. The conformational behavior of the N-arylmethyl-N-hydroxyamino group has been studied using 3/CH NMR coupling data and molecular mechanics computations. Upon spontaneous oxidation, these hydroxylamines led to the corresponding aminoxyl free radicals which were submitted to EPR spectroscopy and quantum mechanical computations at a semiempirical level (PM3). 相似文献
49.
M. Eugenia Pérez‐Ojeda Dr. Beatriz Trastoy Álvaro Rol Dr. María D. Chiara Prof. Dr. Inmaculada García‐Moreno Dr. Jose Luis Chiara 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6630-6640
A general procedure for the assembly of hetero‐bifunctional cubic silsesquioxanes with diverse functionality and a perfectly controlled distribution of functional groups on the inorganic framework has been developed. The method is based on a two‐step sequence of mono‐ and hepta‐functionalization through the ligand‐accelerated copper(I)‐catalyzed azide–alkyne cycloaddition of a readily available octaazido cubic silsesquioxane. The stoichiometry of the reactants and the law of binomial distribution essentially determine the selectivity of the key monofunctionalization reaction when a copper catalyst with strong donor ligands is used. The methodology has been applied to the preparation of a set of bifunctional nano‐building‐blocks with orthogonal reactivity for the controlled assembly of precisely defined hybrid nanomaterials and a fluorescent multivalent probe for application in targeted cell‐imaging. The inorganic cage provides an improved photostability to the covalently attached dye as well as a convenient framework for the 3D multivalent display of the pendant epitopes. Thus, fluorescent bioprobes based on well‐defined cubic silsesquioxanes offer interesting advantages over more conventional fully organic analogues and ill‐defined hybrid nanoparticles and promise to become powerful tools for the study of cell biology and for biomedical applications. 相似文献
50.
Multiresidue determination of UV filters in water samples by solid‐phase extraction and liquid chromatography with tandem mass spectrometry analysis 下载免费PDF全文
Anna Laura Capriotti Chiara Cavaliere Susy Piovesana Roberto Samperi Serena Stampachiacchiere Salvatore Ventura Aldo Laganà 《Journal of separation science》2014,37(20):2882-2891
UV filters, contained in sunscreens and other cosmetic products, as well as in some plastics and industrial products, are nowadays considered contaminants of emerging concern because their widespread and increasing use has lead to their presence in the environment. Furthermore, some UV filters are suspected to have endocrine disruption activity. In the present work, we developed an analytical method based on liquid chromatography with tandem mass spectrometry for the determination of UV filters in tap and lake waters. Sixteen UV filters were extracted from water samples by solid‐phase extraction employing graphitized carbon black as adsorbent material. Handling 200 mL of water sample, satisfactory recoveries were obtained for almost all the analytes. The limits of detection and quantification of the method were comparable to those reported in other works, and ranged between 0.7–3.5 and 1.9–11.8 ng/L, respectively; however in our case the number of investigated compounds was larger. The major encountered problem in method development was to identify the background contamination sources and reduce their contribution. UV filters were not detected in tap water samples, whereas the analyses conducted on samples collected from three different lakes showed that the swimming areas are most subject to UV filter contamination. 相似文献