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Carlos Camacho‐Camacho Irma Rojas‐Oviedo Ariadna Garza‐Ortiz Rubén Alfredo Toscano Luis Sánchez‐Sánchez Jorge Cardenas Hugo López‐Muñoz 《应用有机金属化学》2016,30(4):199-207
The synthesis in one‐pot reactions and structural characterization of six new tri‐n‐butyltin(IV) derivatives of Schiff bases are reported. The compounds are derived from a condensation reaction between l ‐alanine, l ‐valine, l ‐isoleucine, l ‐methionine, l ‐phenylalanine or l ‐tryptophan and 3,5‐di‐tert‐butyl‐2‐hydroxybenzaldehyde. Characterization was completed using elemental analysis, infrared spectroscopy, mass spectrometry, one‐ and two‐dimensional solution NMR (1H, 13C and 119Sn) as well as solid‐state 119Sn NMR. In addition, the crystal structures of three of the compounds were confirmed using single‐crystal X‐ray diffraction. Although five‐coordinated and polymeric in the solid state, the tin compounds are four‐coordinated and monomeric in solution. The coordination environment around the triorganotin units comprises three carbon atoms and two oxygen atoms from two ligands in a trigonal bipyramidal geometry. The anti‐proliferative effect of these compounds on the cervical carcinoma cell lines HeLa, CaSki and ViBo was screened in vitro, the compounds showing cytotoxic activity against all three strains and null or low cytotoxic activity (necrotic) as well. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
53.
Alfredo Lorenzi 《Applicable analysis》2013,92(1):79-96
In this work we prove an existence and uniqueness theorem for solutions in 2(Rt) of second order elliptic equations with coefficients that are constant on the half-spaces R+n and R ?n 相似文献
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Felipe Wodtke Fernando R. Xavier Samuel R. Mendes Alfredo R.M. de Oliveira Rogério A. Gariani 《Tetrahedron letters》2017,58(3):231-234
A novel application of the highly stable niobium oxide phosphate (NbOPO4) as an efficient catalyst for the synthesis of β-enamino ketones under solvent-free conditions is described. This protocol, exhibits attractive yields, short reaction periods, lower loading of catalyst and high chemoselectivity. 相似文献
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Bianca Flavia Bonini Luca Bernardi Mauro Comes-Franchini Gabriella Dessole Mariafrancesca Fochi Alfredo Ricci 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1273-1277
Abstract Enantiomerically pure 2-hydroxyalkyl, 2-aminoalkyl and 2-iminoalkyl ferrocenyl p-tolylsulfides are easily prepared in good yields and with complete diastereocontrol from (S)-(2-p-tolylthio)ferrocencarboxyaldehyde. 2-Iminoalkyl ferrocenyl derivatives can be used as ligands in asymmetric catalysis and as starting materials for asymmetric Staudinger reaction. 相似文献
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Ioana Konz Beatriz Fernández M. Luisa Fernández Rosario Pereiro Héctor González Lydia Álvarez Miguel Coca-Prados Alfredo Sanz-Medel 《Analytical and bioanalytical chemistry》2013,405(10):3091-3096
Laser ablation coupled to inductively coupled plasma mass spectrometry has been developed for the elemental imaging of Mg, Fe and Cu distribution in histological tissue sections of fixed eyes, embedded in paraffin, from human donors (cadavers). This work presents the development of a novel internal standard correction methodology based on the deposition of a homogeneous thin gold film on the tissue surface and the use of the 197Au+ signal as internal standard. Sample preparation (tissue section thickness) and laser conditions were carefully optimized, and internal normalisation using 197Au+ was compared with 13C+ correction for imaging applications. 24Mg+, 56Fe+ and 63Cu+ distributions were investigated in histological sections of the anterior segment of the eye (including the iris, ciliary body, cornea and trabecular meshwork) and were shown to be heterogeneously distributed along those tissue structures. Reproducibility was assessed by imaging different human eye sections from the same donor and from ten different eyes from adult normal donors, which showed that similar spatial maps were obtained and therefore demonstrate the analytical potential of using 197Au+ as internal standard. The proposed analytical approach could offer a robust tool with great practical interest for clinical studies, e.g. to investigate trace element distribution of metals and their alterations in ocular diseases. Figure
Development of a new internal standard correction methodology for qualitative elemental imaging by LA-ICP-MS 相似文献