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1.
J Clin Med ; 13(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38610896

RESUMO

Background: This research aimed to evaluate the association between the monthly consumption of fish (differentiated by type) and both gestational and neonatal outcomes. Methods: Women who were admitted for delivery in the last 6 months of 2023 were prospectively included and divided according to type of fish consumed (based on DHA and mercury content) and frequency of consumption. Neonatal outcomes included weight, length, head circumference, and 1st and 5th minute Apgar scores. Maternal outcomes were threats of abortion, preterm birth, gestational diabetes and hypertension, cesarean section, and differential body mass index (BMI). Results: Small-size oily fish with high DHA and low mercury content (type B fish) consumption was positively associated with neonatal weight and head circumference, and less weight gain in pregnancy. It was also significantly associated with lower incidences of gestational diabetes and hypertension, and cesarean section. Correlation between differential BMI and monthly consumption of fish resulted in statistical significance, especially in type B fish consumers. Conclusions: The consumption of type B fish was significantly associated with increased neonatal weight and head circumference and better maternal outcomes.

2.
Foods ; 12(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37628013

RESUMO

This study investigates consumer behavior and interest in "welfare-friendly" forms of pork production, considering the growing presence of animal welfare-focused breeding practices. The aim is to outline the typical profile of pork consumers and identify the key attributes influencing their purchasing decisions. A survey was conducted on a sample of 286 individuals after excluding those who only consumed beef and/or poultry or identified as vegetarians/vegans. Regression coefficients (b), 95% Confidence Intervals (95% C.I.), and p-values were reported for univariate and multivariate models. Statistical significance was determined at p < 0.05 (indicated in bold). The findings indicate that younger participants show greater sensitivity towards consuming meat raised using welfare-friendly methods, raising considerations about the age composition of the sample. The research's originality lies in evaluating consumer interest in pork raised with animal welfare-respecting techniques. The use of appropriate statistical tools, such as multivariate and multilayer models, allows effective solutions for multidimensional hypothesis testing problems in non-parametric permutation inference.

3.
Diagnostics (Basel) ; 13(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36980361

RESUMO

The presence of involuntary, non-functional jaw muscle activity (NFJMA) has not yet been assessed in patients with disorders of consciousness (DOC), although the presence of bruxism and other forms of movement disorders involving facial muscles is probably more frequent than believed. In this work, we evaluated twenty-two prolonged or chronic DOC patients with a long-lasting polygraphic recording to verify NFJMA occurrence and assess its neurophysiological patterns in this group of patients. A total of 5 out of 22 patients showed the presence of significant NFJMA with electromyographic patterns similar to what can be observed in non-DOC patients with bruxism, thus suggesting a disinhibition of masticatory motor nuclei from the cortical control. On the other hand, in two DOC patients, electromyographic patterns advised for the presence of myorhythmia, thus suggesting a brainstem/diencephalic involvement. Functional, non-invasive tools such as long-lasting polygraphic recordings should be extended to a larger sample of patients, since they are increasingly important in revealing disorders potentially severe and impacting the quality of life of DOC patients.

4.
Foods ; 12(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38231599

RESUMO

In Italy, the consumption of pork meat is increasing, despite consumers' attitudes being addressed toward a greater sensitivity about animal welfare and its link with safe food. Considering the relatively high animal welfare standards and the divergence in public interest in farm animal welfare and ethical issues, the objective of this study-in continuation of our previous paper relating to consumer behavior and preferences in welfare-friendly pork breeding-was to investigate habits of pork consumers regarding pig welfare, principally evaluating their willingness to pay (WTP) a higher price for pork obtained using raising techniques with an approach based on animal welfare. An ad hoc questionnaire-based survey was submitted to consumers (n = 404) in Messina province, Italy. Results suggest that 47% of consumers were willing to pay an additional price for pork from farms that apply specific animal welfare standards. Positive correlations were between WTP and farming techniques (p = 0.001), organic farming methods (p = 0.001), and farms in which animal welfare is taken care of and guaranteed (p < 0.001). These findings suggest that consumers intend to pay a higher price for pork, like other animal products obtained using animal-friendly raising techniques. The sensitivity to the animal welfare of a single human being may influence consumers' attitudes toward pork consumption.

5.
Neuropsychol Rehabil ; 28(8): 1295-1310, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28278590

RESUMO

Pain assessment in patients with disorders of consciousness (DoC) is a controversial issue for clinicians, who require tools and standardised procedures for testing nociception in non-communicative patients. The aims of the present study were, first, to analyse the psychometric properties of the Italian version of the Nociception Coma Scale and, second, to evaluate pressure pain thresholds in a group of patients with DoC. The authors conducted a multi-centre study on 40 healthy participants and 60 DoC patients enrolled from six hospitals in Italy. For each group an electronic algometer was used to apply all nociceptive pressure stimuli. Our results show that the Italian version of the NCS retains the good psychometric properties of the original version and is therefore suitable for standardised pain assessment in clinical practice. In our study, pressure pain thresholds measured in a group of patients in vegetative and minimally conscious state were relatively lower than pain threshold values found in a group of healthy participants. Such findings motivate additional investigation on possible pain sensitisation in patients with severe brain injury and multiple co-morbidities, and on application of tailored therapeutic approaches useful for pain management in patients unable verbally to communicate their feelings.


Assuntos
Transtornos da Consciência/diagnóstico , Transtornos da Consciência/fisiopatologia , Medição da Dor , Limiar da Dor , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Nociceptiva/diagnóstico , Dor Nociceptiva/fisiopatologia , Variações Dependentes do Observador , Pressão , Psicometria , Sensibilidade e Especificidade
6.
Dalton Trans ; (37): 7786-95, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19759954

RESUMO

The reactivity of platinum(II) complexes of the type [PtCl(O,O-acac)(L)] (1) and [Pt(O,O-acac)(gamma-acac)(L)] (2) (L = DMSO, a; DMS, b), with a range of hard and soft nucleophiles such as dimethylsulfide (DMS, b), triphenylphosphine, (PPh3, c), ethylene (eta2-C2H4, d), carbon monoxide (CO, e), pyridine (py, f), and guanosine (Guo, g) has been investigated. Interestingly, the complexes 1a and 1b undergo selective substitution of the chloro or sulfur ligand depending on the hard/soft character of the incoming nucleophile. The soft incoming ligand replaces the softer one and the hard ligand replaces the harder one, giving [PtCl(O,O'-acac)(L)] complexes (1b, 1c, 1d and 1e in the reaction of 1a with L = DMS, PPh3, eta2-C2H4, CO, respectively), and [Pt(O,O'-acac)(DMSO)(L')] (3f, 3g) and [Pt(O,O'-acac)(DMS)(L')] (4f, 4g) species in the reaction of 1a and 1b with L' = py and guo, respectively. In the cases of 2a and 2b complexes, where the pi-bonded acac (gamma-acac) replaces the chloro ligand, only in the presence of an incoming soft nucleophile substituting the soft sulfur ligand the reaction occurs. Equilibrium constants for the substitution reactions were measured by 1H NMR spectroscopy. Variable temperature 1H NMR spectroscopy studies, performed for the reaction of 1a and 2a complexes with DMS, revealed that the selective substitution of DMSO with DMS takes place in both cases, according to a second-order kinetic law. The calculated values of DeltaH++ and DeltaS++ are consistent with an associative mechanism. NMR spectroscopic characterization (1H, 13C, 195Pt, 31P) for the complexes and crystal structures of isolated complexes ([PtCl(O,O'-acac)(L)] (1) and [Pt(O,O'-acac)(gamma-acac)(L)] (2), L = DMSO, 1a and 2a; L = DMS, 1b and 2b; L = PPh3, 1c and 2c) are herein reported and discussed.


Assuntos
Dureza , Cetonas/química , Compostos Organoplatínicos/química , Monóxido de Carbono/química , Cristalografia por Raios X , Etilenos/química , Guanosina/química , Cinética , Ligantes , Espectroscopia de Ressonância Magnética , Compostos Organofosforados/química , Piridinas/química , Especificidade por Substrato , Sulfetos/química , Termodinâmica
7.
Dalton Trans ; (19): 3766-73, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19417942

RESUMO

Two ruthenium(III) complexes structurally similar to the anticancer compound NAMI were prepared: Na[RuCl4(DMSO)(L1)] ( 1) and Na[RuCl4(DMSO)(L2)] ( 2), where L1 and L2 are differently functionalised triazole-thiadiazine ligands. To facilitate the crystallisation of the complex anions, Na+ was substituted with the [bis(triphenylphosphoranylidene)ammonium] cation (PPN+), allowing the X-ray characterisation of PPN[RuCl4(DMSO)(L1)].2H2O ( 1a.2H2O) and PPN[RuCl4(DMSO)(L2)].3H2O ( 2a.3H2O), respectively. The two compounds undergo stepwise hydrolytic processes, as assessed by means of UV-vis and 1H NMR spectroscopy. The first hydrolytic step consists of the replacement of a chloride anion with a water molecule, with a half-life of 50 min ( 1) and 110 min ( 2), while the subsequent hydrolytic steps are more complicated to describe since more than one product is generated at the same time. The redox potential of the Ru(III)/Ru(II) couple (0.31 V for 1 and 0.28 V for 2) suggests that these complexes can be reduced in the intracellular environment, in agreement with the activation by reduction mechanism proposed for NAMI and NAMI-A. 1 and 2 were tested on a human cancer cell line derived from a fibrosarcoma (HT1080), and on non-cancerous primary human fibroblasts (HF), where they showed a modest inhibitory effect.

8.
Inorg Chem ; 47(6): 2223-32, 2008 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-18269219

RESUMO

The heteroscorpionate N, N', S, S' donor ligands 4-methoxy-3,5-dimethyl-2-(3-(methylthio)-1-(3-(2-(methylthio)phenyl)-1H-pyrazol-1-yl)propyl)pyridine (L(a)) and 4-methoxy-3,5-dimethyl-2-(2-(methylthio)-1-(3-(2-(methylthio)phenyl)-1H-pyrazol-1-yl)ethyl)pyridine (L(b)) were prepared. The Cu(I) complexes [Cu(L(a))]2(BF4)2 (a2(BF4)2) and [Cu(L(b))]2(BF4)2 (b2(BF4)2) were synthesized and characterized by X-ray crystallography. Both compounds exhibit a dinuclear structure, presenting each Cu(I) center in a distorted N, N', S, S' tetrahedral environment. On the basis of nuclear magnetic resonance (NMR) and ESI-mass data, the presence of a mononuclear complex in equilibrium with the dimer was hypothesized for both complexes. The dimerization constants of the processes, 2a(+) = a2(2+) and 2b(+) = b2(2+) , were obtained by (1)H NMR dilution experiments (fast-exchange regime) in CD 3CN: log K(a2(2+)) = 3.55(6) and log K(b2(2+)) = 3.23(5) at 300 K. Thermodynamic parameters were determined by a van't Hoff analysis (280-310 K temperature range): DeltaH(0)(a2(2+)) = -12(1) kJ mol (-1), DeltaH(0)(b2(2+)) = -10(1) kJ mol(-1), DeltaS(0)(a2(2+)) = +27(4) kJ mol (-1), and DeltaS(0)(b2(2+)) = +28(4) kJ mol (-1). Pulsed gradient spin-echo (PGSE) NMR experiments provided the weighted-average hydrodynamic volume (VH) of the species present in CD 3CN solution at different copper concentrations (CCu). Nonlinear interpolation of VH as a function of C Cu for a dimer-monomer equilibrium led to the hydrodynamic volumes of both monomers (VH(0)(M)) and dimers (VH(0)(D)): VH(0)(a(+)) = 620(40) A(3), VH(0)(b(+)) = 550(10) A(3), VH(0)(a2(2+)) = 950(20) A(3), and VH(0)(b2(2+)) = 900(10) A(3). Cyclic voltammetry experiments performed in CH3CN and CH2Cl2 showed a quasi-reversible to irreversible behavior of the Cu(I)/Cu(II) redox couple for both complexes.

9.
Inorg Chem ; 46(24): 10143-52, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-17973478

RESUMO

The N,N',S-donor ligand 4-methoxy-3,5-dimethyl-2-((3-(2-(methylthio)phenyl)-1H-pyrazol-1-yl)methyl)pyridine (L) was prepared from 2-(chloromethyl)-4-methoxy-3,5-dimethylpyridine hydrochloride and 3-(2-(methylthio)phenyl)-1H-pyrazole. The Cu(I) complexes [Cu2(L)2CH3CN][Cu(L)CH3CN](BF4)3 (1), [Cu(L)PPh3]BF4 (2), and [Cu6(L)2(C6F5S)6] (3) were prepared and characterized by X-ray crystallography (PPh3=triphenylphosphine, C6F5S-=pentafluorothiophenolate). The unit cell of compound 1 consists of cocrystallized mononuclear and dinuclear entities in which all of the copper atoms exhibit distorted tetrahedral coordination. Compound 2 is monomeric with L bound in the kappa3-N,N',S mode and a PPh3 molecule that completes the coordination environment. Compound 2 presents a fluxional behavior in CDCl3 solution due to the boat inversion of the six-membered N,N' chelate ring (DeltaH=+43.6(3) kJ mol(-1), DeltaS=-16(1) J mol(-1) K(-1)). Crystallization of 3 in acetonitrile leads to a polynuclear structure that contains a CH3CN molecule coordinated to one of the copper atoms: [Cu6(L)2(C6F5S)6CH3CN] (3a). The core of 3a partially resembles a {Cu4S6} adamantane-like moiety, the only difference being that the Cu-NCCH3 interaction leads to the opening of the cluster by disrupting a Cu-Cu interaction. Part of this assembly is found in the yeast metallothionein copper(I)-cysteinate core whose crystal structure has recently been reported. Two additional [Cu(L)]+ peripheral moieties interact with the cluster by means of bridging thiolates. ESI-mass spectrometry, conductivity measurements, and 1H/19F pulsed gradient spin echo (PGSE) NMR experiments suggest that 3a dissociates in acetonitrile solution: 3a+CH3CN-->[Cu4(C6F5S)6]2-+2[Cu(L)CH3CN]+. The stability of the cluster with respect to the hypothetical mononuclear species, [Cu(L)(C6F5S)], is confirmed by DFT calculations (B3LYP), which illustrate the exergonic character of the reaction: 6[Cu(L')(C6H5S)]-->[Cu6(L')2(C6H5S)6]+4L' (DeltaG298=-58.6 kJ mol(-1), where L' and C6H5S- are simplified models for L and C6F5S-, respectively). The energetics pertinent to the ionic dissociation of the cluster in acetonitrile is computed using the polarizable continuum model (PCM) approach.


Assuntos
Cobre/química , Metalotioneína/química , Compostos Organometálicos/síntese química , Cristalografia por Raios X , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Compostos Organometálicos/química
10.
Inorg Chem ; 46(8): 3367-77, 2007 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-17367129

RESUMO

The N,N',O-heteroscorpionate ligand 1-(4-methoxy-3,5-dimethyl-pyridin-2-yl)-2-methyl-1-pyrazol-1-yl-propan-2-ol (LOH) was prepared in two high-yield steps. Complexes [M(LOH)2][MCl4] (M2+ = Cu2+ and Zn2+) and [M(LOH)2]Cl2 (M2+ = Ni2+ and Cu2+) were prepared and characterized by X-ray crystallography. The speciation in solution (methanol:water 95:5) of the M2+/LOH systems was investigated by means of spectrophotometric (Ni2+ and Cu2+) and 1H NMR (Zn2+) titrations. The beta1 and beta2 global formation constants for the [M(LOH)]2+ and [M(LOH)2]2+ species were obtained and are in agreement with the Irving-Williams series: Ni2+< Cu2+> Zn2+. The Zn2+/LOH system was studied by means of quantitative 1H-1H EXSY spectroscopy (300 K, mixing time = 0.2-0.8 s), which allows the description of the equilibria occurring between five octahedral [Zn(LOH)2]2+ structural isomers and tetrahedral [Zn(LOH)Cl]Cl species. Exchange constants kijex and associated rate constants kij suggest that two types of interconversion occur: octahedral-octahedral (faster) and octahedral-tetrahedral (slower). DFT calculations (B3LYP/6-311+G(d)) were employed to evaluate the relative stability of the [Zn(LOH)2]2+ isomers, which are comparable for the five complexes with a maximum energy difference of 6.3 kJ/mol.

11.
J Med Chem ; 50(8): 1916-24, 2007 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-17373781

RESUMO

The thioamido function of [CuCl2(1H)]Cl (2) (1=4-amino-1,4-dihydro-3-(2-pyridyl)-5-thioxo-1,2,4-triazole), a cytotoxic copper complex, was converted into thioether moieties, leading to the synthesis of [CuCl2(3)]2 (4) and [CuCl2(5)] (6) (3=6-methyl-3-pyridin-2-yl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine; 5=4-amino-5-ethylthio-3-(2-pyridyl)-1,2,4-triazole). These complexes were structurally characterized, and their stability constants, along with their biological activity, were determined. 4 and 6 were slightly less stable and significantly less active than 2. However, as 2, both complexes induced nonapoptotic vacuolar cell death. Copper uptake, investigated in both 2-sensitive and -insensitive cell types, was markedly higher in sensitive cells where it was associated with an increase in oxidized glutathione. These data suggest that the thioamido function enhances the cytotoxicity of copper complexes in cancer cells promoting the accumulation of the metal and its interaction with cell thiols.


Assuntos
Antineoplásicos/síntese química , Quelantes/química , Cobre , Compostos Organometálicos/síntese química , Triazóis/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia
12.
Inorg Chem ; 45(8): 3456-66, 2006 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-16602807

RESUMO

Complexes [PPh3Cu(Tr(Mes,Me))] (1), [PPh3Cu(Tr(Me,o-Py))] (2), and [PPh3Cu(Br(Mes)pz(o-Py))] (3) (Tr(Mes,Me) = hydrotris[1,4-dihydro-3-methyl-4-mesityl-5-thioxo-1,2,4-triazolyl]borate; Tr(Me,o-Py) = hydrotris[1,4-dihydro-4-methyl-3-(2-pyridyl)-5-thioxo-1,2,4-triazolyl]borate; Br(Mes)pz(o-Py) = hydro[bis(thioxotriazolyl)-3-(2-pyridyl)pyrazolyl]borate; PPh3 = triphenylphosphine) were synthesized by the reaction of dinuclear complexes [Cu(Tr(Mes,Me))]2, [Cu(Tr(Me,o-Py))]2, [Cu(Br(Mes)pz(o-Py))]2, and PPh3. 1-3 were characterized by 1H, 13C, and 31P NMR spectroscopy and ESI-mass spectrometry. Crystal structure analyses were performed for 1 and 2. Both complexes crystallize in the triclinic P space group with the metal in a slightly distorted tetrahedral geometry (S3P coordination) bound by a kappa3-S3 ligand and a PPh3 molecule. The solution molecular structures were investigated by means of variable-temperature (210-310 K, CDCl3, 1-2; 200-310 K, CD2Cl2, 3) and NOESY NMR spectroscopy. The solution structures of 1-2 are in accordance with the X-ray structures, and the complexes do not exhibit fluxional behavior. On the other hand, 3 is subject to an equilibrium between two species with a coalescing temperature of approximately 260 K. DFT geometry optimizations suggest that the major species of 3 consists of the Br(Mes)pz(o-Py) ligand bound to Cu(I) in the kappa3-S2H fashion with two C=S groups and a [Cu...H-B] interaction. A PPh3 completes the copper coordination (S2HP coordination). The complex [TuCu(Tr(Mes,Me))] (4) (Tu = thiourea) was crystallized using an excess of Tu with respect to [Cu(Tr(Me,2-Py))]2 (approximately a 6:1 ratio). The metal adopts a distorted tetrahedral geometry with an overall S3H coordination determined by the bound kappa3-S2H ligand (two C=S groups and a [B-H...Cu] interaction) and by a Tu. The reactivity of dinuclear complexes [Cu(Tr(Mes,Me))]2, [Cu(Tr(Me,o-Py))]2, and [Cu(Br(Mes)pz(o-Py))]2 with monodentate ligands was investigated by means of NMR titrations with PPh3, Tu. and pyridine (Py), and formation constants for the adducts [DCu(L)] (D = monodentate donor, L = tripodal ligand) were determined.


Assuntos
Cobre/química , Compostos Organometálicos/química , Compostos Organofosforados/química , Piridinas/química , Tioureia/química , Complexo I de Transporte de Elétrons/química , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Titulometria
13.
J Am Chem Soc ; 128(3): 866-76, 2006 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-16417377

RESUMO

Reaction of RNHC(S)PPh2NPPh2C(S)NR (HRSNS; R = Me, Et) with M(I) (M = Cu, Ag, Au) salts afforded zwitterionic complexes of the general formula [M(RSNS)] (M = Cu, Ag, Au). The ligand was found in the solid state in S,S-kappa2 and S,N,S-kappa3 coordination fashions. [Cu(RSNS)] and [Ag(RSNS)] can be used as metalloligand building blocks for the assembly of pentanuclear multizwitterionic Cu5, Cu3Ag2 and Ag5 core clusters of the general formula [M'2{M(RSNS)}3]2+ (M = Cu, M' = Cu, Ag; M = M' = Ag) upon reaction with suitable M' salts. The crystal structures of the most significant compounds are reported herein. Compound [Ag2{Ag(RSNS)}2(OTf)2] was also isolated and structurally characterized, representing a model for the intermediate species of the aforementioned assembly.

14.
J Inorg Biochem ; 99(8): 1573-84, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15953645

RESUMO

The aim of the present study was the synthesis, the determination of formation constants, and the evaluation of the antiproliferative activity of two copper(II) complexes formed with triazole-type ligands. The synthesis of the unsymmetrical triazole ligand 4-amino-3-aminomethyl-5-methyl-1,2,4-triazole (L1), and its copper(II) complex is reported. The ligand was prepared by functionalization of the carboxylate function of tert-butyloxycarbonyl (BOC) protected glycine O-methyl ester. All intermediates and final products were isolated and characterized with IR, 1H NMR, and elemental analysis. X-ray structures of the ligand as a sulfate salt ((H2L1)2SO4.H2O) and the copper(II) complex [CuCl2(L1)(2)] are described. The ligand forms a (N,N) bidentate chelate with the amino group and one triazole nitrogen atom. The tetragonally distorted octahedral coordination of Cu(II) results from two axially coordinated chloride ions. Protonation constants for L1 and speciation of the Cu(II)/L1 system were determined in 0.1 M aqueous KCl solution at 25 degrees C. Complexes formed in solution were also characterized by visible spectrophotometry. Ligand substitution competition between L1 and glycine has also been studied using potentiometric titrations. Antiproliferative activities of ([CuCl2(L1)2]) and [CuCl2(H2L2)]Cl, where HL2 is the 5-thioxo analog of L1, against human tumor cell lines HT1080 and HT29 as well as normal human fibroblasts (HF) are presented along with the antiproliferative activities of L1, CuCl2, and cisplatin. Activity of these two complexes are discussed and compared with the activity of analogous compounds reported in the literature which contain pyridyl groups in place of the aminomethyl group. In particular, it is suggested that a lypophilic residue such as a pyridyl group is important for antiproliferative activity of this class of compounds.


Assuntos
Lactonas/química , Lactonas/farmacologia , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Triazóis/química , Triazóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cloretos/química , Cristalografia por Raios X , Glicina/química , Humanos , Concentração de Íons de Hidrogênio , Lactonas/síntese química , Estrutura Molecular , Compostos Organometálicos/síntese química , Solubilidade , Triazóis/síntese química
15.
Inorg Chem ; 44(12): 4333-45, 2005 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-15934764

RESUMO

Dinuclear Cu(I) complexes with bifunctionalized homoscorpionate ligands, hydrotris(thioxotriazolyl)borato [Li(Tr(Me,o)(-)(Py)) (1) and Li(Tr(Mes,Me)) (2)], and the heteroscorpionate ligand hydro[bis(thioxotriazolyl)-3-(2-pyridyl)pyrazolyl]borato [K(Br(Mes)pz(o)(-)(Py))] (3) were synthesized and crystallographically characterized. The complexes [Cu(Tr(Mes,Me))](2) (4) and [Cu(Tr(Me,o)(-)(Py))](2) (5) exhibit a similar coordination geometry where every metal is surrounded by three thioxo groups in a trigonal arrangement. The presence of a [B-H...Cu] three-center-two-electron interaction in both compounds causes the overall coordination to become tetrahedrally distorted (S(3)H coordination for each metal). The complex [Cu(Br(Mes)pz(o)(-)(Py))](2) (6) presents a trigonal geometry in which the metals interact with two thioxo groups and a bridging pyrazolyl nitrogen atom. A weak contact with a pyridine nitrogen atom completes the coordination of the metals (S(2)N,N' coordination for each metal). [Cu(Tr(Mes,Me))](2), [Cu(Tr(Me,o)(-)(Py))](2), and [Cu(Br(Mes)pz(o)(-)(Py))](2) exhibit fluxional behavior in solution as evidenced by variable-temperature NMR spectroscopy, and for 5 and 6 two species in equilibrium [in the ratio 2/1 for 5 (CDCl(3)) and 3/2 for 6 (CD(2)Cl(2))] are distinguishable in the (1)H NMR spectra at 270 K. 2D-NOESY spectra recorded at 270 K assisted in the attribution of solution molecular geometries for each isomer of 5 and 6. The free energy of activation (DeltaG()(Tc)) was determined for both equilibria from the evaluation of the coalescence temperature. DFT calculations were performed to describe plausible molecular geometry for the minor isomer of 5 and 6 and to propose a possible mechanism of interconversion between major and minor isomers. Cyclic voltammograms were recorded in CH(2)Cl(2) (3 and 6) or CH(2)Cl(2)/CH(3)CN (1/1, v/v) (2, 4, and 5) solutions using 0.1 M TBAHFP or TBAOTf as supporting electrolytes. [Cu(Tr(Mes,Me))](2), [Cu(Tr(Me,o)(-)(Py))](2), and [Cu(Br(Mes)pz(o)(-)(Py))](2) exhibit a quasi-reversible Cu(I)/Cu(II) redox behavior with E(pa) = +719 mV and E(pc) = +538 mV for 4, E(pa) = +636 mV and E(pc) = -316 mV for 5, and E(pa) = +418 mV and E(pc) = -319 mV for 6.

16.
Inorg Chem ; 42(6): 2109-14, 2003 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-12639148

RESUMO

Preparations of copper(I) and bismuth(III) complexes of hydrotris(4-ethyl-3-methyl-5-thioxo-1,2,4-triazolyl)borate (Tr(Et,Me)) are described. These complexes have been characterized by means of spectroscopy and microanalysis. Molecular structures of [Cu(Tr(Et,Me))](2) x 2.5CH(3)CN x 0.5H(2)O (3a) and [Bi(Tr(Et,Me))(2)]NO(3) x 2CHCl(3) (4a) have been determined by single-crystal X-ray diffraction. In the centrosymmetric dimeric copper(I) complex, Tr(Et,Me) acts in the k(3)S,S',H:kS' ' coordination mode. The metal is found in a distorted trigonal geometry as the ligand exhibits an "S(3)-inverted" conformation at the boron center so that a weak [B-H.Cu] agostic interaction renders the overall coordination of the (3 + 1) type. On the other hand, in the bismuth complex, Tr(Et,Me) presents the k(3)S,S',S' ' coordination mode and the "S(3)-normal" conformation. The metal is found in a regular octahedral geometry bound by six thioxo groups of two ligands. Species distributions in solution have been studied using electrospray ionization mass spectrometry upon dissolution of 3a and 4a crystals in acetonitrile. Monomeric and polynuclear copper(I) complexes with different M:L ratios are present in solution, while for 4a only the monomeric species is present.

17.
Inorg Chem ; 42(5): 1769-78, 2003 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-12611552

RESUMO

Reacting the heterocycle 5-thioxo-1,4-dihydro-4-ethyl-3-methyl-1,2,4-triazole (thioxotriazoline) with sodium tetrahydroborate in the molar ratio of approximately 2:1 at 130 degrees C provides the new ligand dihydrobis(thioxotriazolinyl)borato, [Bt(Et,Me)](-), as its sodium salt. The neutral complexes of this anionic ligand with zinc(II), bismuth(III), and nickel(II) have been synthesized and characterized by X-ray crystallography. In every complex, the ligand is coordinated to the metal in the S(2) mode, generating eight-membered chelate rings. The bismuth and nickel complexes exhibit two M.H-B interactions responsible for the dodecahedral and octahedral geometries, respectively. For the zinc complex, the trigonal-bipyramidal coordination is achieved with an apical Zn.H-B interaction. The crystal structures for the three complexes are described, and ab initio calculations on Bi(III), Ni(II), and Zn(II) compounds have been performed in order to assess the nature of the M.H-B interaction and its role for the definition of the molecular geometries.

18.
J Inorg Biochem ; 92(2): 95-104, 2002 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-12459154

RESUMO

Preparations of copper(II) and palladium(II) complexes of 4-amino-5-methylthio-3-(2-pyridyl)-1,2,4-triazole (L(1)) and the copper(II) complex of 1,4-dihydro-4-amino-3-(2-pyridyl)-5-thioxo-1,2,4-triazole (HL) are described. These complexes have been characterized by means of spectroscopy and microanalysis. Molecular structures of HL (1), [CuCl(2)(H(2)L)]Cl.2H(2)O (2a), cis-[CuCl(2)(L(1))] (3), and cis-[PdCl(2)(L(1))] (4) have been determined by single-crystal X-ray diffraction. The HL ligand acts as a N,S bidentate through the thioxo moiety and the exo-amino group whilst the ligand L(1) forms N,N coordination complexes through the pyridine and triazole nitrogen atoms. Speciation in solution of the systems Cu/HL and Cu/L(1) have been determined by means of potentiometry and spectrophotometry as well as for the Cu/L(1)/A (HA=glycine) system in order to determine species present at physiological pH. Antiproliferative activity of these complexes and their ligands was evaluated, using the AlamarBlue Assay, on normal human fibroblasts (HF) and human fibrosarcoma tumor (HT1080) cells. The copper compounds cis-[CuCl(2)(H(2)L)]Cl and cis-[CuCl(2)(L(1))] exerted significant antiproliferative activity of both normal and neoplastic cells; although dose-response experiments revealed that the HT1080 cell line was more sensitive to the tested drugs than normal fibroblasts.


Assuntos
Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Cobre/química , Cristalografia por Raios X , Humanos , Estrutura Molecular , Compostos Organometálicos/farmacologia , Paládio/química , Soluções , Triazóis/síntese química , Triazóis/química , Triazóis/farmacologia
20.
Angew Chem Int Ed Engl ; 40(13): 2495-2497, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29712297

RESUMO

Doubly bridged di(silyl-η-amido)cyclopentadienyltitanium and -zirconium complexes and their related cations as the [(PhCH2 )B(C6 F5 )3 ]- salts have been isolated (see structure of the Ti derivative). The neutral benzylzirconium complex was a very efficient catalyst in the presence of methylaluminoxane for producing high molecular weight polyethylene and ethylene-1-hexene copolymers.

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