0000000000082616
AUTHOR
Estefanía Delgado-pinar
Metal Complexes as Receptors
The role played by metal complexes as receptors of different substrates is discussed. For this purpose, several relevant examples of the work performed by different research groups have been briefly discussed. The metal complexes have been organized attending to the molecular topology of the ligands employed. The article ends with the description of metallocages in which at least one of the metal ions constituting the cage framework binds the guest through coordinative bonds.
One-pot preparation of surface modified boehmite nanoparticles with rare-earth cyclen complexes.
We report on the one-pot synthetic procedure of cyclen derivatives bearing three acetate groups attached on boehmite nanoparticles, the complexing capabilities of these inorganic–organic hybrid materials with rare earth cations, and the behaviour as contrast agents or fluorescence probes. Delgado Pinar, Estefania, Estefania.Delgado@uv.es ; Frias Martinez, Juan Carlos, Juan.Frias@uv.es ; Albelda Gimeno, Maria Teresa, Teresa.Albelda@uv.es ; Alarcon Navarro, Javier, Javier.Alarcon@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es
Preparation of Hg2+ selective fluorescent chemosensors based on surface modified core–shell aluminosilicate nanoparticles
A synthetic procedure for the preparation of functional structured inorganic–organic hybrid materials consisting of boehmite-silica core–shell nanoparticles and anthracene-containing amines covalently attached to the nanoparticles surface is reported. The system functionalised with the monoamine chain shows a very high sensing performance for Hg2+ detection in pure water reaching a detection limit of 0.2 ppb. Two additional advantages of these systems are their stability over a wide pH window and the feasibility to be recovered by a simple procedure.
Microstructural evolution of mullites produced from single-phase gels
The crystalline microstructure of mullites obtained by heating monophasic gels has been investigated. Gels with alumina to silica molar ratio of 3:2 (as in secondary mullite) and 2:1 (as in primary mullite) were prepared by gelling mixtures of aluminium nitrate and tetraethylorthosilicate. Phase transformations were induced by heating the gel precursors, with different final treatment temperatures between 1173 and 1873 K. The mullites formed as a result of thermal treatment were studied by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The crystalline structure (unit-cell parameters) and microstructure were determined from X-ray diffraction pa…
Triazolopyridines. Part 28. The ring–chain isomerization strategy: triazolopyridine- and triazoloquinoline–pyridine based fluorescence ligands
Abstract The ring–chain isomerization of [1,2,3]triazolo[1,5-a]pyridines or [1,2,3]triazolo[1,5-a] quinolines has been efficiently employed as a tool to provide tridentate fluorescent structures. Based on these scaffolds, a new family of highly fluorescent compounds has been synthesized and evaluated for the recognition of zinc or copper cations. In addition, the 1:1 Zn+2-L complex of a naphthalene triazolopyridine–pyridine derivative revealed high efficiency as sensor for anions providing large binding constants for nitrite and cyanide.
New polyamine drugs as more effective antichagas agents than benznidazole in both the acute and chronic phases.
Abstract Despite the continuous research effort that has been made in recent years to find ways to treat the potentially life threatening Chagas disease (CD), this remains the third most important infectious disease in Latin America. CD is an important public health problem affecting 6–7 million people. Since the need to search for new drugs for the treatment of DC persists, in this article we present a panel of new polyamines based on the tripodal structure of tris(2-aminomethyl)amine (tren) that can be prepared at low cost with high yields. Moreover, these polyamines present the characteristic of being water-soluble and resistant to the acidic pH values of stomach, which would allow their…
Correlation between the molecular structure and the kinetics of decomposition of azamacrocyclic copper(II) complexes
The formation of copper(II) complexes with symmetrical dinucleating macrocyclic ligands containing two either monomethylated (L1) or trimethylated (L2) diethylenetriamine (Medien or Me3dien) subunits linked by pyridine spacers has been studied by potentiometry. Potentiometric studies show that L1 has larger basicity than L2 as well as higher stability of its mono- and binuclear complexes. The crystal structures of L1·6HCl (1), [Cu2(L1)Cl2](CF3SO3)2 (2), [Cu2(L1)(OH)](ClO4)3·3H2O (3) and [Cu(L1)](ClO4)2 (4) show that L1 adopts different coordination modes when bound to copper(II). Whereas in 2, each copper(II) is bound to one Medien subunit and to one pyridine group, in 3 each metal center i…
Naphthalene-containing polyamines supported in nanosized boehmite particles
Boehmite nanoparticles with covalently linked polyamine chains functionalized with naphthalene fluorophores have been prepared and characterized. The characterization of the materials by elemental microanalysis, X-ray powder diffraction, MAS 29Si NMR and electron microscopy unambiguously prove that the covalent anchorage had occurred. Steady-state fluorescence emission studies show that the luminescent properties of the modified nanoparticles are sensitive to changes in concentration of hydrogen ions, metal ions and anionic nucleotides such as ATP. The behaviour of the attached materials in aqueous solution is parallel to the behaviour of the single fluorophoric polyamines. Comparisons are …
Grafted squaramide monoamine nanoparticles as simple systems for sulfate recognition in pure water.
New simple systems formed by a chain containing a squaramide function and a quaternised amine group attached to boehmite or silica-coated boehmite nanoparticles are able to discriminate anions in pure water.
Pb2+complexes of small-cavity azamacrocyclic ligands: thermodynamic and kinetic studies
The synthesis, acid-base behavior and Pb2+ coordination chemistry of the new aza-scorpiand like ligand 5-[2-(N-2-fluorenyl)ethylamino]-2,5,8-triaza[9]-2,6-pyridinophane (L1) have been studied by potentiometry, NMR and spectrofluorimetric titrations, and the results are compared with those obtained for the related compounds L2, lacking the fluorenyl group, and L3, the macrocycle lacking the pendant arm. The crystal structures obtained for complexes [PbL1][PbL1Cl](NO3)Cl2·4H2O (1) and [PbL3](ClO4)2 (2) reveal that the metal ion is located over the plane defined by the nitrogen atoms of the macrocyclic core due to its inability to accommodate the large Pb2+ ion in the macrocyclic cavity. For L…
Linear, tripodal, macrocyclic: Ligand geometry and ORR activity of supported Pd(II) complexes
Abstract The novel ligand H3L designed to spontaneously adsorb onto MWCNT via electron-deficient pyrimidine residues and bind metal cations is used to prepare an oxygen reduction reaction (ORR) cathode catalyst based on supported Pd(II) complexes. Herein we report the synthesis of the ligand, its solution behaviour (protonation constants, binding constants for the test cation Cu(II), UV evidence of Cu(II) and Pd(II) complexes formation) and ORR performances together with XPS and STEM characterization. Tripodal nature of the H3L ligand frame it in-between previously studied macrocyclic and linear open chain ligands, allowing to draw meaningful comparisons.
In silico discovery of substituted pyrido[2,3-d]pyrimidines and pentamidine-like compounds with biological activity in myotonic dystrophy models
Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approach…
Heterocyclic Diamines with Leishmanicidal Activity.
Leishmaniasis is one of the world's most neglected diseases with a worldwide prevalence of 12 million people. There are no effective human vaccines for its prevention, and outdated drugs hamper treatment. Therefore, research aimed at developing new therapeutic tools to fight leishmaniasis remains a crucial goal today. With this purpose in mind, here, we present 10 new compounds made up by linking alkylated ethylenediamine units to pyridine or quinoline heterocycles with promising in vitro and in vivo efficacy against promastigote and amastigote forms of Leishmania infantum, Leishmania donovani, and Leishmania braziliensis species. Three compounds (2, 4, and 5) showed a selectivity index muc…
Lanthanide complexes as imaging agents anchored on nano-sized particles of boehmite
International audience; The synthesis of boehmite nanoparticles modified with lanthanides (Eu, Tb and Gd) is described. Their synthesis, characterization and in vitro assays with HeLa cells were performed. The nuclear magnetic relaxation dispersion (NMRD) profiles of the two chelating moieties were studied. Imaging data from laser scanning confocal fluorescence microscopy and flow cytometry revealed that the nanoscaffolds were taken up by the cells, distributed throughout the cytoplasm and showed no toxicity. This platform could represent an alternative to silica-based inert matrices as imaging vehicles.
<strong>Synthesis and Platinum (II) Complexes of Different Polyazacyclophane Receptors</strong>
During the last years, research on coordination chemistry of platinum has aroused great interest due to their potential biological applications. Herein, we report the interaction of PtCI42- with different polyazacyclophanes containing a pyridine unit as aromatic spacer. Formation of complexes has been studied by 1H and 195Pt NMR spectroscopy. Analysis of the recorded spectra of D2O solutions containing L and PtCl42- in a 1:1 molar ratio at acidic pH shows the evolution with time of the 1H and 195Pt signals. Different crystal structures have been solved by X-ray diffraction analysis. At acidic pHs, the metal ion is coordinated by the central amino group of the macrocyclic cavity and three ch…
Molecular Switching, Logics, and Memories
The concepts of molecular switch, molecular logics and memories are intimately related. In this work a review of these three topics is given. While the main examples concern the field of inorganic chemistry, in a few cases organic systems are presented to better illustrate the concepts. The basic notions of the logics gates usually used by the nowadays computers is presented and the modus operandi to transpose these concepts to the molecular level is discussed. Examples of switches driven by external stimuli such as light-induced, metal-ion, redox, photobistable, and complexation–decomplexation are described in this chapter. The extension of switches working in solution to solid devices are…
Oligonucleotide-Hybridization Fiber-Optic Biosensor using a Narrow Bandwidth Long Period Grating
Nanometric narrowband Long Period Gratings (LPG) are investigated for the implementation of improved fiber optic biosensors. The reduction of more than one order of magnitude in the linewidth of the LPG with respect standard LPG at 1500 nm, leads to the improvement of the resolution of the sensor. By selecting the proper fabrication parameters (high numerical aperture, relatively high order mode and large length), LPGs with a 3-dB bandwidth of 1.5 nm were fabricated. The sensitivity of the LPG as a refractometer was calculated, and experimentally characterized in detail. In particular, the LP0,17 and LP0,18 resonances were investigated, in order to select the most suitable one for the bioex…
CCDC 1964484: Experimental Crystal Structure Determination
Related Article: Nadine Leygue, Chantal Galaup, Alberto Lopera, Estefanía Delgado-Pinar, René M. Williams, Heinz Gornitzka, Jurriaan M. Zwier, Enrique García-España, Laurent Lamarque, Claude Picard|2020|Inorg.Chem.|59|1496|doi:10.1021/acs.inorgchem.9b03345
CCDC 1009322: Experimental Crystal Structure Determination
Related Article: Laura Acosta-Rueda, Estefanía Delgado-Pinar, Javier Pitarch-Jarque, Alexis Rodríguez, Salvador Blasco, Jorge González, Manuel G. Basallote, Enrique García-España|2015|Dalton Trans.|44|8255|doi:10.1039/C5DT00408J
CCDC 1009323: Experimental Crystal Structure Determination
Related Article: Laura Acosta-Rueda, Estefanía Delgado-Pinar, Javier Pitarch-Jarque, Alexis Rodríguez, Salvador Blasco, Jorge González, Manuel G. Basallote, Enrique García-España|2015|Dalton Trans.|44|8255|doi:10.1039/C5DT00408J
CCDC 1009325: Experimental Crystal Structure Determination
Related Article: Laura Acosta-Rueda, Estefanía Delgado-Pinar, Javier Pitarch-Jarque, Alexis Rodríguez, Salvador Blasco, Jorge González, Manuel G. Basallote, Enrique García-España|2015|Dalton Trans.|44|8255|doi:10.1039/C5DT00408J
CCDC 1827335: Experimental Crystal Structure Determination
Related Article: Álvaro Martínez-Camarena, Andrea Liberato, Estefanía Delgado-Pinar, Andrés G. Algarra, Javier Pitarch-Jarque, José M. Llinares, M. Ángeles Mañez, Antonio Domenech-Carbó, Manuel G. Basallote, Enrique García-España|2018|Inorg.Chem.|57|10961|doi:10.1021/acs.inorgchem.8b01492
CCDC 2192965: Experimental Crystal Structure Determination
Related Article: Valeria Dantignana, M. Carmen Pérez-Segura, Pau Besalú-Sala, Estefanía Delgado-Pinar, Álvaro Martínez-Camarena, Joan Serrano-Plana, Andrea Álvarez-Núñez, Carmen E. Castillo, Enrique García-España, Josep M. Luis, Manuel G. Basallote, Miquel Costas, Anna Company|2023|Angew.Chem.,Int.Ed.|62||doi:10.1002/anie.202211361
CCDC 2192964: Experimental Crystal Structure Determination
Related Article: Valeria Dantignana, M. Carmen Pérez-Segura, Pau Besalú-Sala, Estefanía Delgado-Pinar, Álvaro Martínez-Camarena, Joan Serrano-Plana, Andrea Álvarez-Núñez, Carmen E. Castillo, Enrique García-España, Josep M. Luis, Manuel G. Basallote, Miquel Costas, Anna Company|2023|Angew.Chem.,Int.Ed.|62||doi:10.1002/anie.202211361
CCDC 1827337: Experimental Crystal Structure Determination
Related Article: Álvaro Martínez-Camarena, Andrea Liberato, Estefanía Delgado-Pinar, Andrés G. Algarra, Javier Pitarch-Jarque, José M. Llinares, M. Ángeles Mañez, Antonio Domenech-Carbó, Manuel G. Basallote, Enrique García-España|2018|Inorg.Chem.|57|10961|doi:10.1021/acs.inorgchem.8b01492
CCDC 1840192: Experimental Crystal Structure Determination
Related Article: Ruixi Fan, Joan Serrano-Plana, Williamson N. Oloo, Apparao Draksharapu, Estefanía Delgado-Pinar, Anna Company, Vlad Martin-Diaconescu, Margarida Borrell, Julio Lloret-Fillol, Enrique García-España, Yisong Guo, Emile L. Bominaar, Lawrence Que Junior, Miquel Costas, Eckard Münck|2018|J.Am.Chem.Soc.|140|3916|doi:10.1021/jacs.7b11400
CCDC 2192963: Experimental Crystal Structure Determination
Related Article: Valeria Dantignana, M. Carmen Pérez-Segura, Pau Besalú-Sala, Estefanía Delgado-Pinar, Álvaro Martínez-Camarena, Joan Serrano-Plana, Andrea Álvarez-Núñez, Carmen E. Castillo, Enrique García-España, Josep M. Luis, Manuel G. Basallote, Miquel Costas, Anna Company|2023|Angew.Chem.,Int.Ed.|62||doi:10.1002/anie.202211361
CCDC 1009324: Experimental Crystal Structure Determination
Related Article: Laura Acosta-Rueda, Estefanía Delgado-Pinar, Javier Pitarch-Jarque, Alexis Rodríguez, Salvador Blasco, Jorge González, Manuel G. Basallote, Enrique García-España|2015|Dalton Trans.|44|8255|doi:10.1039/C5DT00408J
CCDC 1827336: Experimental Crystal Structure Determination
Related Article: Álvaro Martínez-Camarena, Andrea Liberato, Estefanía Delgado-Pinar, Andrés G. Algarra, Javier Pitarch-Jarque, José M. Llinares, M. Ángeles Mañez, Antonio Domenech-Carbó, Manuel G. Basallote, Enrique García-España|2018|Inorg.Chem.|57|10961|doi:10.1021/acs.inorgchem.8b01492
CCDC 2192962: Experimental Crystal Structure Determination
Related Article: Valeria Dantignana, M. Carmen Pérez-Segura, Pau Besalú-Sala, Estefanía Delgado-Pinar, Álvaro Martínez-Camarena, Joan Serrano-Plana, Andrea Álvarez-Núñez, Carmen E. Castillo, Enrique García-España, Josep M. Luis, Manuel G. Basallote, Miquel Costas, Anna Company|2023|Angew.Chem.,Int.Ed.|62||doi:10.1002/anie.202211361