Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 14 de 14
1.
Cir Cir ; 90(2): 256-261, 2022.
Article En | MEDLINE | ID: mdl-35350055

Hemorrhagic liver rupture is a rare and deadly complication. The pathogenesis is unknown. This situation forces the multidisciplinary team, the immediate termination of pregnancy, the treatment and management of the patient in an intensive care unit (ICU). We report the results of two patients with spontaneous rupture of the liver during pregnancy and HELLP (hemolysis, elevated liver enzymes, low platelet count) syndrome, asymptomatic, during cesarean section, with management in ICU, poor evolution without adequate response; one died and the other leaves hospital. Liver rupture requires high suspicion and timely, aggressive multidisciplinary management in all cases and surgical intervention in those who develop liver ruptura, to improve survival.


La hemorragia por ruptura hepática es una rara y letal complicación, de etiología desconocida. Obliga al equipo multidisciplinario a la interrupción del embarazo, al tratamiento agresivo y al manejo de la paciente en una unidad de cuidado intensivo (UCI). Se presentan dos pacientes con embarazo de término con ruptura de hematoma hepático subcapsular asociado a síndrome HELLP (hemolysis, elevated liver enzymes, low platelet count), asintomáticas, durante operación cesárea, con manejo en UCI, ambas con evolución tórpida; una fallece y la otra se egresa. La ruptura hepática requiere una alta sospecha y un manejo multidisciplinario oportuno, agresivo en todos los casos y de intervención quirúrgica en quienes desarrollen ruptura hepática, para mejorar la supervivencia.


HELLP Syndrome , Liver Diseases , Ranunculaceae , Cesarean Section/adverse effects , Female , HELLP Syndrome/surgery , HELLP Syndrome/therapy , Humans , Liver Diseases/surgery , Pregnancy , Rupture, Spontaneous
2.
Molecules ; 26(5)2021 Mar 05.
Article En | MEDLINE | ID: mdl-33807775

We describe the synthesis of fluorogenic arylureas and amides and their interaction with primary or secondary amines under air and light in organic-aqueous mixtures to give rise to a new class of persistent organic radicals, described on the basis of their electron paramagnetic resonance (EPR), as well as UV-vis, fluorescence, NMR, and quantum mechanics calculations, and their prospective use as multi-signal reporters in a smart label for fish freshness.


Amides/chemical synthesis , Amines/chemistry , Fish Products/analysis , Fluorescent Dyes/chemical synthesis , Food Analysis/methods , Amides/chemistry , Animals , Electron Spin Resonance Spectroscopy , Fluorescence , Fluorescent Dyes/chemistry , Free Radicals/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Perciformes
3.
Org Lett ; 21(15): 5803-5807, 2019 08 02.
Article En | MEDLINE | ID: mdl-31241968

We report the use of a tetraborylated perylenediimide as starting material for the preparation of a tetracorannulene-perylenediimide that is able to bind up to two fullerene-C60 molecules by host-guest molecular recognition with preference over C70. Titration with fullerene-C60 is followed by a dramatic shift of the aromatic signals in 1H NMR and an initial increase in the fluorescence of the system. By this simple mechanism, fluorogenic sensing of fullerene-C60 is easily accomplished by an unprecedented fluorescent turn-on mechanism.

4.
Chemistry ; 24(66): 17523-17537, 2018 Nov 27.
Article En | MEDLINE | ID: mdl-30176086

In this paper, the synthesis, comprehensive characterization and biological and photocatalytic properties of two series of neutral IrIII biscyclometalated complexes of general formula [Ir(C^N)2 (N^O)], where the N^O ligands are 2-(benzimidazolyl)phenolate-N,O (L1, series a) and 2-(benzothiazolyl)phenolate-N,O (L2, series b), and the C^N ligands are 2-(phenyl)pyridinate or its derivatives, are described,. Complexes of types a and b exhibit dissimilar photophysical and biological properties. In vitro cytotoxicity tests conclusively prove that derivatives of series a are harmless in the dark against SW480 cancer cells (colon adenocarcinoma), but express enhanced cytotoxicity versus the same cells after stimulation with UV or blue light. In contrast, complexes of type b show a very high cytotoxic activity in the dark, but low photosensitizing ability. Thus, the ancillary N^O ligand is the main factor in terms of cytotoxic activity both in the dark and upon irradiation. However, the C^N ligands play a key role regarding cellular uptake. In particular, the complex of formula [Ir(dfppy)2 (L1)] (dfppy=2-(4,6-difluorophenyl)pyridinate) [3 a] has been identified as both an efficient photosensitizer for 1 O2 generation and a potential agent for photodynamic therapy. These capabilities are probably related to a combination of its notable cellular internalization, remarkable photostability, high photoluminescence quantum yield, and long triplet excited-state lifetime. Both types of complexes exhibit notable catalytic activity in the photooxidation of thioanisole and S-containing aminoacids with full selectivity.


Coordination Complexes/chemistry , Iridium/chemistry , Ligands , Photosensitizing Agents/chemical synthesis , Azoles/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Colonic Neoplasms/diagnostic imaging , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Crystallography, X-Ray , Drug Stability , Electrochemical Techniques , Humans , Hydroxybenzoates/chemistry , Light , Microscopy, Fluorescence , Molecular Conformation , Photochemotherapy , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Quantum Theory , Reactive Oxygen Species/metabolism , Spectrometry, Fluorescence
5.
Inorg Chem ; 57(3): 970-984, 2018 Feb 05.
Article En | MEDLINE | ID: mdl-29303596

Precursors of chelate pyridine-N-heterocyclic carbene (N^C:) ligands with methyl- or benzyl-substituted imidazolylidene fragments were synthesized. They were used to obtain 12 iridium bis-cyclometalated complexes of the type [Ir(C^N)2(N^C:)]+ (C^N = 2-(phenyl)pyridinato-C2,N, ppy, 2-(4,6-difluorophenyl)pyridinato-C2,N, dfppy). The ancillary N^C: ligands contain different structural modifications. The aim of the work was to analyze the effect that changes in the two types of ligands have on the photophysical and electrochemical properties and also on the behavior of these materials as photosensitizers. The X-ray crystal structures of five complexes were determined. The complexes emitted in the blue-green region. It was expected that the frontier orbitals and thus the photophysical and electrochemical properties would be controlled by the main C^N ligands, and it was demonstrated that the effect of the modifications in the N^C: ligand, especially the presence of a nitro group in the pyridine ring or the interruption of conjugation between the two rings, also affected these properties. The quenching with O2 and photostability studies were also performed. Density functional theory calculations were used to explain the behavior of some derivatives. The complexes and other previously reported compounds were employed as photosensitizers (PS) in preliminary studies on the production of H2 from water using [Co(bpy)3]Cl2 (bpy = 2,2'-bipyridine) as catalyst and triethanolamine (TEOA) as the sacrificial reductant. The absence of quenching of the PS with TEOA allowed us to propose an oxidative quenching mechanism.

6.
Chemistry ; 23(56): 13973-13979, 2017 Oct 09.
Article En | MEDLINE | ID: mdl-28731620

A fluorogenic perylenediimide-functionalized polyacrylate capable of generating color and fluorescence changes in the presence of triacetone triperoxide TATP), an improvised explosive used in terrorist attacks, under solvent-free, solid-state conditions has been developed. The material works by accumulating volatile TATP until it reaches a threshold; therefore, triggering colorimetric and fluorescent responses.

7.
Dalton Trans ; 45(35): 13888-98, 2016 Sep 21.
Article En | MEDLINE | ID: mdl-27523928

(1)H NMR spectroscopy at 400 MHz in toluene-d8 of evaporated mixtures of lithium ethoxide and titanium(iv) isopropoxide in ethanol, used to prepare the spinel Li4Ti5O12 by the sol-gel method, may help clarify why the atomic ratio 5Li : 5Ti and not 4Li : 5Ti is the right choice to obtain the pure phase when performing hydrolysis at room temperature. The mixtures xLiOEt/yTi(OPr(i))4 in ethanol undergo alcohol exchange at room temperature, and the evaporated residues contain double lithium-titanium ethoxide [LiTi3(OEt)13] rather than simple mixtures of single metal alkoxides; this is of great relevance to truly understanding the chemistry and structural changes in the sol-gel process. Detailed inspection of the (1)H and (13)C VT NMR spectra of mixtures with different Li/Ti atomic ratios unequivocally shows the formation of [LiTi3(OEt)13] in a solution at low temperature. The methylene signals of free lithium ethoxide and Li[Ti3(OEt)13] coalesce at 20 °C when the atomic ratio is 5 : 5; however, the same coalescence is only observed above 60 °C when the atomic ratio is 4 : 5. We suggest that the highest chemical equivalence observed by (1)H NMR spectroscopy achieved through chemical exchange of ethoxide groups involves the highest microscopic structural homogeneity of the sol precursor and will lead to the best gel after hydrolysis. Variable temperature (1)H NMR spectra at 400 MHz of variable molar ratios of LiOEt/Ti(OPr(i))4 are discussed to understand the structural features of the sol precursor. While the precursor with the atomic ratio 5Li : 5Ti shows no signal of free LiOEt at 20 °C, both 4Li : 5Ti and 7Li : 5Ti show free LiOEt at 20 °C in their (1)H NMR spectra, indicating that the molar ratio 5Li : 5Ti gives the maximum rate of chemical exchange. DFT calculations have been performed to support the structure of the anion [Ti3(OEt)13](-) at room temperature.

8.
J Org Chem ; 80(1): 30-9, 2015 Jan 02.
Article En | MEDLINE | ID: mdl-25414966

The reaction of N-(2-phthalimidoethyl)-N-alkylisopropylamines and S2Cl2 gave 4-N-(2-phthalimidoethyl)-N-alkylamino-5-chloro-1,2-dithiol-3-thiones that quantitatively cycloadded to dimethyl or diethyl acetylenedicarboxylate to give stable thioacid chlorides, which in turn reacted with one equivalent of aniline or a thiole to give thioanilides or a dithioester. Several compounds of this series showed atropisomers that were studied by a combination of dynamic NMR, simulation of the signals, conformational analysis by DFT methods, and single crystal X-ray diffraction, showing a good correlation between the theoretical calculations, the experimental values of energies, and the preferred conformations in the solid state. The steric hindering of the crowded substitution at the central amine group was found to be the reason for the presence of permanent atropisomers in this series of compounds and the cause of a unique disposition of the thioxo group at close-to-right angles with respect to the plane defined by the 1,3-dithiole ring in the dithiafulvene derivatives, thus breaking the sulfur-sulfur hypervalent bond that is always found in this kind of compounds.


Sulfur/chemistry , Thioamides/chemistry , Molecular Structure , Quantum Theory , Rotation , Thioamides/chemical synthesis
9.
J Org Chem ; 79(5): 2213-25, 2014 Mar 07.
Article En | MEDLINE | ID: mdl-24511994

The scandium triflate-catalyzed cycloaddition reaction of polycyclic 1,2-dithiolethiones to maleimides is described. The reaction constitutes an easy approach to linear as well as branched oligomeric cis-fused dihydro[1,3]dithiolo[4,5-c]pyrrole-4,6-dione rings interconnected by 3,5-diylidenethiomorpholine-2,6-dithione or ylidene-6-thioxo[1,2]dithiolo[3,4-b][1,4]thiazin-3-one groups. The presence of highly colored, highly polarized push-pull α,ß-unsaturated thione groups in their structures make these compounds sensitive to the presence of mercury(II) cation in organic or mixed organic/aqueous solvents.

10.
Chem Asian J ; 8(6): 1271-8, 2013 Jun.
Article En | MEDLINE | ID: mdl-23495242

We report new indene derivatives that are good fluorogenic probes for the cyanide anion, one of which is a highly selective and sensitive fluorogenic probe for the fluorescent detection--as well as reliable quantification--of the cyanide anion in water or buffer, with a 10(3)-fold increase of fluorescence and low detection limit. It is therefore useful for the quantification of natural cyanide from aqueous extracts of green almond seeds, thus proving that the system is suitable for fast detection and quantification of cyanide from natural sources.


Cyanides/analysis , Fluorescent Dyes/chemical synthesis , Indenes/chemical synthesis , Drinking Water/chemistry , Fluorescent Dyes/chemistry , Indenes/chemistry , Limit of Detection , Models, Molecular , Molecular Structure , Prunus/chemistry , Seeds/chemistry
11.
Chem Commun (Camb) ; 47(11): 3183-5, 2011 Mar 21.
Article En | MEDLINE | ID: mdl-21279204

A fluorescent probe for ω-aminoacids behaves as a molecular ruler, changing the yellow fluorescent emission into blue as a function of the distance between the terminal ammonium and the carboxylate groups, permitting the quantitative detection of ω-aminoacids, their metabolites and related drugs, such as pregabalin or gabapentin, from pharmaceutical formulations.


Amino Acids/chemistry , Fluorescent Dyes/chemistry , Carboxylic Acids/chemistry , Catalysis , Coordination Complexes/chemistry , Quaternary Ammonium Compounds/chemistry
12.
Chem Asian J ; 5(7): 1692-9, 2010 Jul 05.
Article En | MEDLINE | ID: mdl-20533432

The synthesis of some new polysulfur-nitrogen heterocycles by cycloaddition of an ynamine to bisdithiolothiazine ketothiones or dithiones is described and the interconversion between regioisomers is studied by DFT calculations, showing that the double bond isomerizes at room temperature. This series is a new selective and sensitive chromogenic probe for the naked-eye detection of mercury(II) cation and cyanide anion in buffered (HEPES 0.05 M, pH 7.14) water/acetonitrile 1:1 mixture, with sub-micromolar sensitivity, and constitutes the first example of a new class of colorimetric chemical probes for Hg(2+) and CN(-).

13.
Inorg Chem ; 46(2): 568-77, 2007 Jan 22.
Article En | MEDLINE | ID: mdl-17279837

The complexes [MCl(2)(kappa2-N approximately N')] (N approximately N' = 2-C(5)H(4)N-CH2-NHAr; Ar = 4-MeC(6)H(4), a; 2,6-Me(2)C(6)H(3), b; 4-MeOC(6)H(4), c; 4-CF(3)C(6)H(4), d; M = Pd, 1a-d; Pt, 2a-d) have been prepared and fully stereochemically characterized both in the solid state and in solution. Their behavior in DMSO-d6 solution is dependent on the substituents of the aryl group and on the metal. Complexes of palladium with substituents at the para position (1a, 1c, 1d) display a dynamic 1H NMR pattern when the solutions are heated. An enantiomeric exchange Slambda/Rdelta is suggested to explain such behavior. On the basis of the calculated negative DeltaS values, an associative mechanism involving the solvent is proposed. Under the same conditions, analogous complexes of platinum (2a, 2c, 2d) proved to be unstable, and release of the N approximately N' ligand was observed. Complexes 1b and 2b show temperature-variable 1H NMR spectra without any evidence accounting for enantiomeric exchange or decoordination. DFT calculations on models of 1a and 1b show that diastereomeric exchange Sdelta/Slambda is a process where the complex with the higher sterical hindrance, 1b, has a lower energy barrier.

14.
Inorg Chem ; 45(6): 2483-93, 2006 Mar 20.
Article En | MEDLINE | ID: mdl-16529469

Coordination of N,N' bidentate ligands aryl-pyridin-2-ylmethyl-amine ArNH-CH2-2-C5H4N 1 (Ar = 4-CH3-C6H4, 1a; 4-CH3O-C6H4, 1b; 2,6-(CH3)2-C6H3, 1c; 4-CF3-C6H4, 1d) to the moieties [Ru(bipy)2]2+, [Ru(eta5-C5H5)L]+ (L = CH3CN, CO), or [Ru(eta6-arene)Cl]2+ (arene = benzene, p-cymene) occurs under diastereoselective or diastereospecific conditions. Detailed stereochemical analysis of the new complexes is included. The coordination of these secondary amine ligands activates their oxidation to imines by molecular oxygen in a base-catalyzed reaction and hydrogen peroxide was detected as byproduct. The amine-to-imine oxidation was also observed under the experimental conditions of cyclic voltammetry measurements. Deprotonation of the coordinated amine ligands afforded isolatable amido complexes only for the ligand (1-methyl-1-pyridin-2-yl-ethyl)-p-tolyl-amine, 1e, which doesn't contain hydrogen atoms in a beta position relative to the N-H bond. The structures of [Ru(2,2'-bipyridine)2(1b)](PF6)2, 2b; [Ru(2,2'-bipyridine)(2)(1c)](PF6)2, 2c; trans-[RuCl2(COD)(1a)], 3; and [RuCl2(eta6-C6H6)(1a)]PF6, 4a, have been confirmed by X-ray diffraction studies.

...