0000000001305053

AUTHOR

Pilar Navarro

Binuclear Cu2+ complex mediated discrimination between L-glutamate and L-aspartate in water.

L-Glutamate and L-aspartate selectivity is achieved by the action of two Cu2+ metal ions rightly disposed in a cyclophanetype macrocyclic framework; electrochemical sensing of glutamate has been achieved by adsorption of the copper complexes on graphite electrodes. Verdejo Viu, Begoña, Begona.Verdejo@uv.es ; Domenech Carbo, Antonio, Antonio.Domenech@uv.es ; Jimenez Garcia, Hermas Rafael, Hermas.Jimenez@uv.es ; Soriano Soto, Concepción, Concepcion.Soriano@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es

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The structure of ammonium pyrazolates in the solid state

The crystals obtained by mixing equimolar amounts of diethyl 1H-pyrazole-3,5-dicarboxylate and the primary amines phenethylamine and homoveratrylamine are ammonium pyrazolate salts as determined by 13C and 15N CPMAS NMR. Copyright © 2006 John Wiley & Sons, Ltd.

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Vegetable and Fruit Intakes Are Associated with hs-CRP Levels in Pre-Pubertal Girls

The influence of diet on inflammation in children remains unclear. We aimed to analyze the influence of diet on high-sensitivity C-reactive protein (hs-CRP) levels in a pre-pubertal population free of other influences that may affect hs-CRP levels. We determined hs-CRP levels in 571 six- to eight-year-old children using an hs-CRP ELISA kit. Information on food and nutrient intake was obtained through a food-frequency questionnaire. Overall dietary quality was assessed using the Healthy Eating Index (HEI). We found that girls in the highest tertile of hs-CRP levels had a higher intake of saturated fatty acid, and lower intakes of fiber and vitamin E and a lower HEI score when compared to tho…

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A new macrocyclic dipyrazolate salt of diazatetraester structure able to efficiently and selectively interact with psychotropic phenethylammonium salts

Abstract The equilibrium stability constants (Ks) of a series of ammonium pyrazolate complexes [L22−]2RN(R′)H2+ (7, R′=H and 8, R′=Me) formed from a new macrocyclic disodium dipyrazolate salt of diazatetraester structure 6[L22−] 2Na+ and ammonium salts [RNH3+X− or RN(Me)H2+X−] of psychotropic drugs and neurotransmitter catecholamines has been evaluated by electrochemical methods in DMSO solution. The resulting Ks values demonstrate that in general, the diazatetraester crown-derived dipyrazolate salt 6 exerts a stronger complexing effect over phenethylammonium ions than that of the dioxatetraester crown-derived disodium dipyrazolate salt 2 previously reported. Interestingly, complexes formed…

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Acid–base behaviour and binding to double stranded DNA/RNA of benzo[g]phthalazine-based ligands

The affinity and the binding mode of two benzo[g]phthalazine compounds, functionalized with one or two 2-(imidazole-4-yl)-ethylamine groups, to DNA and RNA models have been evaluated by means of UV-Vis, fluorescence and circular dichroism (CD) spectroscopies in combination with viscometry and molecular dynamics. Both organic molecules bind strongly to all nucleic acid models via the intercalation mode in the duplex structure, especially compound 1. Intriguingly, 1 exhibits different emission responses depending on the base composition of duplex DNA/RNAs, which points out the possibility of using it as a base selective nucleic acid probe. Moreover, the acid-base behaviour of both compounds h…

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Self-assembly of 3,5-bis(ethoxycarbonyl)pyrazolate anions and ammonium cations of β-phenylethylamine or homoveratrylamine into hetero-double-stranded helical structures

Hydrogen-bonded double-stranded hetero-helices are formed when reacting sodium 3,5-bis(ethoxycarbonyl)pyrazolate with beta-phenethylammonium or homoveratrylammonium chloride, in which one of the strands is defined by the ammonium cations and the other one by the pyrazolate anions.

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A water molecule in the interior of a 1H-pyrazole Cu2+ metallocage

Water has a great tendency to associate through hydrogen bonding with water molecules or other hydrogen bond donor or acceptor groups. Here the case of a water molecule encapsulated in the interior of a metallocage receptor is presented. The association of four copper(II) ions and two aza-macrocyclic receptors in which two 1H-pyrazole units are connected by cadaverine diamines leads to the inclusion of a water molecule into the cage, as proved by X-ray analysis and infrared spectroscopy. The included water molecule shows no hydrogen bonding with any component of the cage presenting only a weak hydrogen bond with an oxygen atom of a perchlorate counter-anion. The IR stretching vibrations pre…

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Electrochemical determination of the stability of complexes formed by proton-ionizable ligands of 3,5-disubstituted 1H-pyrazole with phenethylamine

The application of two extreme models for diffusion in two-component systems to electrochemically determine equilibrium constants is discussed. The application of cyclic voltammetric, diferential pulse and rotating-disc electrode voltammetric data to elucidate the stoichiometry and formation constant of complex species by applying a generalization of the molar-ratio method is described. Molar-ratio experiments permit the distinction between the limiting diffusive regimes. The values of the equilibrium stability constants for complexation of phenethylamine and phenethylammonium ions by a 26-membered dioxotetraester crown of 3,5-disubstituted 1H-pyrazole as free ligand 1[L] and as dipyrazolat…

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Electrochemistry of copper complexes with macrocyclic polyamines containing pyrazole units.

The voltammetric behaviour of bi- and mono-nuclear complexes formed in solution by Cu(2+) with three polyazacyclophanes containing pyrazole units in aqueous solution is described. Cyclic and square wave voltammetric responses at glassy carbon electrodes indicate that the reduction of copper-macrocycle complexes in solution takes place in two successive one-electron per Cu transfer processes coupled with preorganization and protonation reactions that mimic the behaviour of superoxide dismutase. The electrochemistry of ternary Cu(2+)-receptor-dopamine complexes exhibits significant differences with respect to the protection of the neurotransmitter from post-electron transfer cyclization react…

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Dopamine interaction with a polyamine cryptand of 1H-pyrazole in the absence and in the presence of Cu(II) ions. Crystal structure of [Cu2(H21L](ClO4)3·2H2O

The crystal structure of the binuclear Cu2+ complex [Cu2(H21L)](ClO4)3·2H2O of the cryptand L = 1,4,7,8,11,14,17,20,21,24,29,32,33,36-tetradecaazapentacyclo[12.12.12.1^(6,9).1^(19,22),1,^31,34]hentetraconta-6,9(41),19(40), 21,31,34(39)-hexaene is presented; evidence for the formation in solution of binary L–dopamine and ternary Cu2+–L– dopamine complexes is presented. Escarti Alemany, Francisco, Francisco.Escarti@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es ; Latorre Saborit, Julio, Julio.Latorre@uv.es

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Dopamine interaction with a polyamine cryptand of 1H-pyrazole in the absence and in the presence of Cu(ii) ions. Crystal structure of [Cu2(H−1L](ClO4)3·2H2O

The crystal structure of the binuclear Cu2+ complex [Cu2(H−1L)](ClO4)3 ·2H2O of the cryptand L = 1,4,7,8,11,14,17,20,21,24,29,32,33,36-tetradecaazapentacyclo[12.12.12.1 6,9.119,22,1,31,34]hentetraconta-6,9(41), 19(40), 21,31,34(39)-hexaene is presented; evidence for the formation in solution of binary L–dopamine and ternary Cu2+–L–dopamine complexes is presented.

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CuIIand ZnIICoordination Chemistry of Pyrazole‐Containing Polyamine Receptors − Influence of the Hydrocarbon Side Chain Length on the Metal Coordination

The synthesis of a new macrocyclic receptor (L 4 ) containing two 3,5-dimethylpyrazole units connected by dipropylenetriamine bridges is reported for the first time; pH-metric titrations indicate that L 4 shows six protonation steps in the pH range 2-11. In the absence of metal ions, the pyrazole moieties are not involved in acid-base processes in this pH range. Addition of Cu I I and Zn I I results in deprotonation of the pyrazole moieties which act as bis(monodentate) η 1 :η 1 ligands. This induced deprotonation occurs at higher pH values than in the complexes of the analogous ligand containing diethylenetriamine bridges (L 1 ). The crystal structures of [Cu 2 (H - 2 L 4 )](ClO 4 ) 2 and …

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In vitro and in vivo trypanosomicidal activity of pyrazole-containing macrocyclic and macrobicyclic polyamines: their action on acute and chronic phases of Chagas disease.

The in vitro and in vivo anti- Trypanosoma cruzi activity of the pyrazole-containing macrobicyclic polyamine 1 and N-methyl- and N-benzyl-substituted monocyclic polyamines 2 and 3 was studied. Activity against both the acute and chronic phases of Chagas disease was considered. The compounds were more active against the parasite and less toxic against Vero cells than the reference drug benznidazole, but 1 and 2 were especially effective, where cryptand 1 was the most active, particularly in the chronic phase. The activity results found for these compounds were complemented and discussed by considering their inhibitory effect on the iron superoxide dismutase enzyme of the parasite, the nature…

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Cu2+-Induced formation of cage-like compounds containing pyrazole macrocycles

The crystal structure of the complex [Cu4(H22L)2(H2O)2- (ClO4)2](ClO4)2·2H2O where L is a new pyrazole ligand containing 1,5-diaminopentane spacers represents a new form of obtaining metal ion-induced inorganic–organic cages. Escarti Alemany, Francisco, franesa@alumni.uv.es ; Latorre Saborit, Julio, Julio.Latorre@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es

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Zn(II)-coordination and fluorescence studies of a new polyazamacrocycle incorporating 1H-pyrazole and naphthalene units.

The synthesis and Zn(2+) coordination properties of a new macrocycle (L1) obtained by dipodal (2 + 2) condensation of the polyamine 3-(naphthalen-2-ylmethyl)pentane-1,5-diamine with 1H-pyrazole-3,5-dicarbaldehyde are reported. pH-metric studies show that L1 bears five measurable protonation steps in the 2.0-11.0 pH range. Fluorescence emission studies indicate that the removal of the first proton from the H(5)L1(5+) species leads to a significant decrease in the emission due to a photoinduced electron transfer process. Addition of Zn(2+) promotes a boat-like conformation that approaches both fluorophores and facilitates the formation of an excimer which reaches its highest emission for a 1 …

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Simple dialkyl pyrazole-3,5-dicarboxylates show in vitro and in vivo activity against disease-causing trypanosomatids.

SUMMARYThe synthesis and antiprotozoal activity of some simple dialkyl pyrazole-3,5-dicarboxylates (compounds 2–6) and their sodium salts (pyrazolates) (compounds 7–9) against Trypanosoma cruzi, Leishmania infantum and Leishmania braziliensis are reported. In most cases the studied compounds showed, especially against the clinically significant amastigote forms, in vitro activities higher than those of the reference drugs (benznidazole for T. cruzi and glucantime for Leishmania spp.); furthermore, the low non-specific cytotoxicities against Vero cells and macrophages shown by these compounds led to good selectivity indexes, which are 8–72 times higher for T. cruzi amastigotes and 15–113 tim…

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Electrocatalysis of the oxidation of methylenedioxyamphetamines at electrodes modified with cerium-doped zirconias

The catalytic effect of monoclinic and tetragonal cerium-doped zirconias (m-CexZr1−xO2 and t-CexZr1−xO2, 0<x<0.10, respectively), prepared from gel precursors, on the oxidation of methylenedioxyamphetamine (MDA) and methylenedioxymetamphetamine (MDMA) at pH 7.0 has been studied. Upon attachment of synthetic specimens to polymer film electrodes, an oxidation peak near to +1.05 V vs AgCl/Ag appears that is unaffected by chloride ions and common interfering compounds, namely, dopamine, norepinephrine and ascorbic acid. The catalytic effect appears to be strongly influenced by crystallinity of specimens and coordination of cerium, increasing from the amorphous starting material to t-CexZr1−xO2 …

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From isolated 1H-pyrazole cryptand anion receptors to hybrid inorganic-organic 1D helical polymeric anion receptors

We report a novel 1-D helical coordination polymer formed by protonated polyamine 1H-pyrazole cryptands interconnected by Cu2+ metal ions that are able to encapsulate anionic species behaving as a multianion receptor. Switching from a monomeric receptor to a polymeric receptor is activated by metal ions and pH.

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>3 + 1 = 6 + 2> In Cu(ii) coordination chemistry of 1H-pyrazole aza cryptands

A polyazamacrocycle formed from two tris(2-aminoethyl)amine units connected by 1H-pyrazole units shows unique hexanuclear Cu(ii) complexes by combination of two binuclear Cu(ii) cryptand complexes through pyrazolate moieties belonging to both cryptands. The formation of these dimeric entities has been proven both in solution by potentiometric studies and mass spectroscopy and in the solid state by X-ray diffraction of crystals of three different batches of formulae [Cu6(H-3L)2(H2O)2](TsO)6·22H2O (2), [Cu6(H-3L)2(NO3)2](NO3)4·2H2O (3) and [Cu6(H-3L)2Cl2]Cl4·(C4H5N3O2)2·14.35H2O (4). The hexanuclear unit in 2 and 4 can be viewed like three magnetically independent binuclear complexes with J =…

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Synthesis and cytotoxic activity of a new potential DNA bisintercalator: 1,4-Bis{3-[N-(4-chlorobenzo[g]phthalazin-1-yl)aminopropyl]}piperazine

The synthesis of new 1,4-bisalkylamino (2-4) and 1-alkylamino-4-chloro (5-6) substituted benzo[g]phthalazines is reported. Compounds 2-4 and 6 were prepared both in the free and heteroaromatic ring protonated forms. Bifunctional 6 contains the 1,4-bisaminopropylpiperazine chain as a linker between the two heteroaromatic units, whereas 5 is its monofunctional analogue. The in vitro antitumour activity of the synthesized compounds has been tested against human colon, breast and lung carcinoma cells, and also against human glioblastoma cells. Results obtained show that all of them are active in all cases, but bifunctional 6·2HCl is remarkably effective against the four cell lines tested, exhib…

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Effective complexation of psychotropic phenethylammonium salts from a disodium dipyrazolate salt of macrocyclic structure

The equilibrium stability constants (Ks) of ammonium pyrazolate complexes [L2−]2RN(R′)H2+ (3, R′ = H and 4, R′ = Me) formed from a macrocyclic disodium dipyrazolate salt 2[L2−] 2Na+ and ammonium salts (RNH3+X− or RN(Me)H2+X−) of psychotropic drugs and neurotransmitter catecholamines have been evaluated by electrochemical methods in DMSO solution. The resulting Ks values demonstrate that, except for (±)-amphetamine, the complexes formed by lipophilic primary [mescaline, (+)-amphetamine, (±)-p-methoxyamphetamine (PMA), (±)-3,4-methylenedioxyamphetamine (MDA)] and secondary [(±)-methamphetamine, (+)-methamphetamine and (±)-3,4-methylenedioxymethamphetamine (MDMA ‘ecstasy’)] phenethylamines are…

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In vitro leishmanicidal activity of pyrazole-containing polyamine macrocycles which inhibit the Fe-SOD enzyme of Leishmania infantum and Leishmania braziliensis species

The in vitro leishmanicidal activity and cytotoxicity of pyrazole-containing macrocyclic polyamines 1-4 was assayed on Leishmania infantum and Leishmania braziliensis species. Compounds 1-4 were more active and less toxic than glucantime and both infection rates and ultrastructural alterations confirmed that 1 and 2 were highly leishmanicidal and induced extensive parasite cell damage. Modifications in the excretion products of parasites treated with 1-3 were also consistent with substantial cytoplasm alterations. Compound 2 was highlighted as a potent inhibitor of Fe-SOD in both species, whereas its effect on human CuZn-SOD was poor. Molecular modelling suggested that 2 could deactivate Fe…

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Selective electrochemical discrimination between dopamine and phenethylamine-derived psychotropic drugs using electrodes modified with an acyclic receptor containing two terminal 3-alkoxy-5-nitroindazole rings.

Electrochemical discrimination between dopamine and psychotropic drugs which have in common a skeletal structure of phenethylamine, can be obtained using acyclic receptors L(1) and L(2), containing two terminal 3-alkoxy-5-nitroindazole rings. Upon attachment to graphite electrodes, L(1) and L(2) exhibit a well-defined, essentially reversible solid state electrochemistry in contact with aqueous media, based on electrolyte-assisted reduction processes involving successive cation and anion insertion/binding. As a result, a distinctive, essentially Nernstian electrochemical response is obtained for phenethylammonium ions of methamphetamine (METH), p-methoxyamphetamine (PMA), amphetamine (AMPH),…

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Hydrogen-bond-mediated self-assembly of 26-membered diaza tetraester crowns of 3,5-disubstituted 1 h -pyrazole. Dimerization study in the solid state and in CDCl3 solution

By using an improved synthetic method reported earlier, the cyclic stannoxanes obtained from RN-diethanolamine (R = Me, Bu) and dibutyltin oxide have been reacted with 1H-pyrazole-3,5-dicarbonyl dichloride to afford 26-membered diaza tetraester crowns (1, R = Me; 3, R = Bu) and 39-membered triaza hexaester crowns (2, R = Me; 4, R = Bu). The new structures were identified from their analytical and spectroscopic (1H and 13C NMR, FAB-MS, and/or ESI-MS) data. Both diaza tetraester crowns (1 and 3), containing two 1H-pyrazole units, self-assemble into dimeric species through the formation of four hydrogen bonds involving the two NH pyrazole groups and the two tertiary amine groups of both crowns…

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CCDC 1468808: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Salvador Blasco, Pilar Navarro, Roberto Tejero, José Miguel Junquera-Hernández, Vicente Pérez-Mondéjar, Enrique García-España|2016|New J.Chem.|40|5670|doi:10.1039/C5NJ03234B

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CCDC 892312: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Salvador Blasco, Pilar Navarro, Roberto Tejero, José Miguel Junquera-Hernández, Vicente Pérez-Mondéjar, Enrique García-España|2016|New J.Chem.|40|5670|doi:10.1039/C5NJ03234B

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CCDC 983275: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Laura García-España, José M. Llinares, FangFang Pan, Kari Rissanen, Pilar Navarro, Enrique García-España|2015|Dalton Trans.|44|7761|doi:10.1039/C5DT00763A

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CCDC 1030676: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Laura García-España, José M. Llinares, FangFang Pan, Kari Rissanen, Pilar Navarro, Enrique García-España|2015|Dalton Trans.|44|7761|doi:10.1039/C5DT00763A

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CCDC 1468807: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Salvador Blasco, Pilar Navarro, Roberto Tejero, José Miguel Junquera-Hernández, Vicente Pérez-Mondéjar, Enrique García-España|2016|New J.Chem.|40|5670|doi:10.1039/C5NJ03234B

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CCDC 983272: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Francesc Lloret, Jesús Ferrando-Soria, Pilar Navarro, Alberto Lopera, Enrique García-España|2015|Dalton Trans.|44|3378|doi:10.1039/C4DT03650F

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CCDC 983271: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Francesc Lloret, Jesús Ferrando-Soria, Pilar Navarro, Alberto Lopera, Enrique García-España|2015|Dalton Trans.|44|3378|doi:10.1039/C4DT03650F

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CCDC 892315: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Salvador Blasco, Pilar Navarro, Roberto Tejero, José Miguel Junquera-Hernández, Vicente Pérez-Mondéjar, Enrique García-España|2016|New J.Chem.|40|5670|doi:10.1039/C5NJ03234B

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CCDC 983274: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Francesc Lloret, Jesús Ferrando-Soria, Pilar Navarro, Alberto Lopera, Enrique García-España|2015|Dalton Trans.|44|3378|doi:10.1039/C4DT03650F

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CCDC 983273: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Francesc Lloret, Jesús Ferrando-Soria, Pilar Navarro, Alberto Lopera, Enrique García-España|2015|Dalton Trans.|44|3378|doi:10.1039/C4DT03650F

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CCDC 892316: Experimental Crystal Structure Determination

Related Article: Javier Pitarch-Jarque, Raquel Belda, Salvador Blasco, Pilar Navarro, Roberto Tejero, José Miguel Junquera-Hernández, Vicente Pérez-Mondéjar, Enrique García-España|2016|New J.Chem.|40|5670|doi:10.1039/C5NJ03234B

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