Synthesis, characterization, X-ray structure and in vitro anti mycobacterial and antitumoral activities of Ru(II) phosphine/diimine complexes containing the "SpymMe(2)" ligand, SpymMe(2)=4,6-dimethyl-2-mercaptopyrimidine

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ruthenium(II) phosphine/diimine/picolinate complexes: Inorganic compounds as agents against tuberculosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mono- and dinuclear palladium(II) compounds containing N,S donor ligands - Synthesis, characterization and thermal behavior

Synthesis, spectroscopic characterization and thermal analysis of the compounds [Pd-2(dmba)(2)(mu-NCO)(mu-2-qnS)] (1), [Pd-2(dmba)(2)(mu-NCO)(mu-8-qnS)] (2), [Pd(2-qnS)(2)] (3) and [Pd(8-qn(S))2] (4) (dmba=N,N-dimethylbenzylamine; 2-qnS=2-quinolinethiolate; 8-qnS=8-quinolinethiolate) are described. The thermal decomposition of these compounds occurs in four consecutive steps and the final decomposition products were identified as Pd(0) by X-ray powder diffraction. The thermal stability order of the complexes is 4 > 3 > 1 > 2.

Synthesis, X-ray structure and antimycobacterial activity of silver complexes with alpha-hydroxycarboxylic acids

In this paper, synthesis, characterization and antimycobacterial properties of a new water-soluble complex identified as silver-mandelate are described. Elemental and thermal analyses are consistent with the formula [Ag(C6H5C(OH)COO)](n). The polymeric structure was determined by single X-ray diffraction and the two-dimensional structure is based on the bis(carboxylate-O,O') dimer [Ag-O, 2.237(3), 2.222(3) angstrom]. The structure is extended along both the b and c axes through two oxygen atoms of a bidentate alpha-hydroxyl-carboxylate residue [Ag-OH(hydroxyl), 2.477(3) angstrom; Ag-O(carboxylate), 2.502(3) angstrom; O-Ag-O, 63.94(9)degrees]. A strong d(10)-d(10) interaction was observed between two silver atoms. The Ag...Ag distance is 2.8307(15) angstrom. The NMR C-13 spectrum in D2O shows that coordination of the ligand to Ag(l) occurs through the carboxylate group in solution. Potentiometric titration shows that only species with a molar metaHigand ratio of 2:2 are formed in aqueous solution. The mandelate complex and the silver-glycolate, silver-malate and silver-hydrogen-tartarate complexes were tested against three types of mycobacteria, Mycobacterium avium, Mycobacterium tuberculosis and Mycobacterium kansasii, and their minimal inhibitory concentration (MIC) values were determined. The results show that the four complexes are potential candidates for antiseptic or disinfectant drugs for discharged secretions of patients affected with tuberculosis. (c) 2006 Published by Elsevier B.V.

Crystal structure, DNA binding studies, nucleolytic property and topoisomerase I inhibition of zinc complex with 1,10-phenanthroline and 3-methyl-picolinic acid

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bis[(4-methylphenyl)ethynyl] telluride

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Thermal studies on solid 1,4-bis(3-carboxy-3-oxo-prop-1-enyl) benzene of lighter trivalent lanthanides

Solid-state compounds of general formula Ln(2)L(3)center dot nH(2)O, where L represents 1,4-bis(3-carboxy-3-oxo-prop-1-enyl)benzene and Ln = La, Ce, Pr, Nd, Sm, were synthesized. Complexometric titrations with EDTA, thermogravimetry (TG), differential thermal analysis (DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, elemental analysis and infrared spectroscopy have been employed to characterize and to study the thermal behavior of these compounds in dynamic air atmosphere. The results led to information about the composition, dehydration, crystallinity, and thermal decomposition of the synthesized compounds.

Nanoparticles of octakis [3-(3-amino-1,2,4-triazole)propyl] octasilsesquioxane as ligands for Cu(II), Ni(II), Cd(II), Zn(II), and Fe(III) in aqueous solution

Nanoparticles of octakis[3-(3-amino-1,2,4-triazole)propyl]octasilsesquioxane (ATZ-SSQ) were tested as ligands, for transition-metal ions in aqueous solution with a special attention to sorption isotherms, ligand-metal interaction, and determination of metal ions in natural waters. The adsorption potential of the material ATZ-SSQ was compared with related [3(3-amino-1,2,4-triazole)propyl]silica gel (ATZ-SG). The adsorption was performed using a batchwise process and both organofunctionalized surfaces showed the ability to adsorb the metal ions from aqueous solution. The Langmuir model was used to simulate the sorption isotherms. The results suggest that the sorption of these metals on ATZ-SSQ and ATZ-SG occurs mainly by surface complexation. The equilibrium condition is reached at time lower than 3 min for ATZ-SSQ, while for ATZ-SG is only reached at time of 25 min. The maximum metal ion uptake values for ATZ-SSQ were higher than the corresponding values achieved with the ATZ-SG. In order to obtain more information on the ligand-metal interaction of the complexes on the surface of the ATZ-SSQ nanomaterial, ESR study with various degrees of copper loadings was carried out. The ATZ-SSQ was tested for the determination (in flow using a column technique) of the metal ions present in natural waters. (C) 2007 Elsevier B.V. All rights reserved.

A novel nanostructured composite formed by interaction of copper octa(3-aminopropyl)octasilsesquioxane with azide ligands: Preparation, characterization and a voltammetric application

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

KIR genes and their human leukocyte antigen ligands in the progression to cirrhosis in patients with chronic hepatitis C

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Hemodynamics and bispectral index (BIS) of dogs anesthetized with midazolam and ketamine associated with medetomidine or dexmedetomidine and submitted to ovariohysterectomy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Noradrenaline and mixed alpha(2)-adrenoceptor/imidazoline-receptor ligands: effects on sodium intake

The effect of noradrenaline, and mixed ligands to alpha(2)-adrenoceptors (alpha(2)-AR) and imidazoline receptors (IR), injected intracerebroventricularly (i.c.v.), on sodium intake of sodium depleted rats, was tested against idazoxan, a mixed antagonist ligand to alpha(2)-AR and IR. The inhibition of sodium intake induced by noradrenaline (80 nmol) was completely reversed by idazoxan (160 and 320 nmol) injected i.c.v. The inhibition of sodium intake induced by mixed ligands to alpha(2)-AR and IR, UK14,304, guanabenz and moxonidine, was antagonized from 50 to 60% by idazoxan i.c.v. The results demonstrate that noradrenaline, a non-ligand for IR, acts on alpha(2)-AR inhibiting sodium intake. The possibility that either alpha(2)-AR or IR mediate the effect of mixed agonists on sodium intake remains an open question. (C) 1999 Elsevier B.V. B.V. All rights reserved.

Structure of human PNP complexed with ligands

Purine nucleoside phosphorylase (PNP) is a key enzyme in the purine-salvage pathway, which allows cells to utilize preformed bases and nucleosides in order to synthesize nucleotides. PNP is specific for purine nucleosides in the beta-configuration and exhibits a strong preference for purines containing a 6-keto group and ribosyl-containing nucleosides relative to the corresponding analogues. PNP was crystallized in complex with ligands and data collection was performed using synchrotron radiation. This work reports the structure of human PNP in complex with guanosine (at 2.80 angstrom resolution), 3' deoxyguanosine (at 2.86 angstrom resolution) and 8-azaguanine (at 2.85 angstrom resolution). These structures were compared with the PNP-guanine, PNP-inosine and PNP-immucillin-H complexes solved previously.

Determining the structural basis for specificity of ligands using crystallographic screening

Crystallographic screening has been used to identify new inhibitors for potential target for drug development. Here, we describe the application of the crystallographic screening to assess the structural basis of specificity of ligands against a protein target. The method is efficient and results in detailed crystallographic information. The utility of the method is demonstrated in the study of the structural basis for specificity of ligands for human purine nucleoside phosphorylase (PNP). Purine nucleoside phosphorylase catalyzes the phosphorolysis of the N-ribosidic bonds of purine nucleosides and deoxynucleosides. This enzyme is a target for inhibitor development aiming at T-cell immune response modulation and has been submitted to extensive structure-based drug design. This methodology may help in the future development of a new generation of PNP inhibitors.

Phase behavior of the orange essential oil/sodium bis(2-ethylhexyl)sulfosuccinate/water system

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)