Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Med Chem ; 46(6): 1992-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21474217

RESUMO

Novel molecular complexes of 1,10-phenanthroline (phen) and 5-amino-1,10-phenanthroline (5-NH2-phen) [(5-NH2-phen)2(phen) (H2O)3 (1), (phen)2(imidazole) (H+) (BF4-) (2), (phen)2(benzimidazole) (H+) (BF4-) (3), (5-NH2-phen)4(H2O)3 (4), and (phen)3 (indole) (H+) (BF4-) (5)] were synthesized via self-assembly processes and their in vitro anticancer activity was investigated. The structures of the compounds were confirmed by UV, FTIR, CIMS(CH4) and elemental analysis. The crystal structure of 2 was determined by X-ray diffraction. Cytotoxicity of the substances was measured using the cultivated human tumour cell lines HepG2, HEp-2, and 8-MB-GA. The tested substances showed different activity depending on the cell line and amount used. Substances 2 and 3 were not toxic to the non-tumour cells (Lep-3), but significantly toxic to all tumour ones. This is not the case with compounds 4 and 5, which are non-toxic towards carcinogenic cell lines, but even stimulate both HepG2 and HEp-2.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Fenantrolinas/química , Fenantrolinas/síntese química , Fenantrolinas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Conformação Molecular , Estereoisomerismo , Relação Estrutura-Atividade
2.
Artigo em Inglês | MEDLINE | ID: mdl-19931483

RESUMO

The novel 3-phenylpyridinium hydrogensquarate (1) has been synthesized and its structure and properties are elucidated spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy, TGA, DSC, DTA and ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectrum. 3-Phenylpyridinium hydrogensquarate, crystallizes in the space group P-1 and the ions in the unit cell are joined into layers by intermolecular NH...O=C((Sq)) bonds with bond lengths of 2.625 and 2.626 A, respectively. Hydrogentartarates form dimers by strong O=COH...OCO interactions (2.499 A).


Assuntos
Compostos de Piridínio/química , Análise Espectral/métodos , Cristalização , Desenho de Fármacos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Compostos de Piridínio/síntese química , Espectrofotometria Infravermelho , Difração de Raios X
3.
Biometals ; 23(1): 59-70, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19768636

RESUMO

Alkaline-earth metal complexes of the monoanionic form of the polyether ionophore monensin A were isolated for the first time in solid state and were structurally characterized using various spectroscopic methods (IR, NMR, FAB-MS). The stoichiometric reaction of monensic acid (MonH) with M(2+) (M = Mg, Ca) in the presence of an organic base leads to the formation of mononuclear complexes of composition [M(Mon)(2)(H(2)O)(2)]. The structures of magnesium (1) and calcium (2) monensin complexes in the solid state were established by single crystal X-ray crystallography. The complexes crystallize as [Mg(Mon)(2)(H(2)O)(2)]x5MeCN (1) and [Ca(Mon)(2)(H(2)O)(2)]xH(2)Ox5MeCN (2) in the monoclinic P21 space group. The alkaline-earth metal ion is placed in a distorted octahedral environment, defined by two monensin anions acting as bidentate ligands in the equatorial plane of the complex as well as by two water molecules occupying the axial positions of the inner coordination sphere. The bactericidal activity of 1 and 2 was evaluated against aerobic Gram-positive microorganisms applying the double layer agar hole diffusion method.


Assuntos
Bacillus/efeitos dos fármacos , Furanos/química , Metais Alcalinoterrosos/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Ácidos Pentanoicos/química , Sarcina/efeitos dos fármacos , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Bacillus/citologia , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Furanos/síntese química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Ácidos Pentanoicos/síntese química , Sarcina/citologia , Espectrofotometria Infravermelho
4.
J Inorg Biochem ; 103(10): 1419-24, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19748125

RESUMO

The preparation and structural characterization of a new copper(II) complex of the polyether ionophorous antibiotic sodium monensin A (MonNa) are described. Sodium monensin A binds Cu(II) to produce a heterometallic complex of composition [Cu(MonNa)(2)Cl(2)].H(2)O, 1. The crystallographic data of 1 show that the complex crystallizes in monoclinic space group C2 with Cu(II) ion adopting a distorted square-planar geometry. Copper(II) coordinates two anionic sodium monensin ligands and two chloride anions producing a neutral compound. The sodium ion remains in the inner cavity of the ligand retaining its sixfold coordination with oxygen atoms. Replacement of crystallization water by acetonitrile is observed in the crystal structure of the complex 1. Copper(I) salt of the methyl ester of MonNa, 2, was identified by X-ray crystallography as a side product of the reaction of MonNa with Cu(II). Compound 2, [Me-MonNa][H-MonNa][CuCl(2)]Cl, crystallizes in monoclinic space group C2 with the same coordination pattern of the sodium cation but contains a chlorocuprate(I) counter [CuCl(2)](-), which is linear and not coordinated by sodium monensin A. The antibacterial and antioxidant properties as two independent activities of 1 were studied. Compound 1 is effective against aerobic Gram(+)-microorganisms Bacillus subtilis, Bacillus mycoides and Sarcina lutea. Complex 1 shows SOD-like activity comparable with that of the copper(II) ion.


Assuntos
Antibacterianos/química , Cobre/química , Monensin/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Cobre/farmacologia , Cristalografia por Raios X , Bactérias Gram-Positivas/crescimento & desenvolvimento , Estrutura Molecular , Monensin/farmacologia
5.
Amino Acids ; 36(1): 29-33, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18188664

RESUMO

Tyrammonium 4-nitrophthalate has been synthesized and its structural and spectroscopic properties elucidated by single-crystal X-ray diffraction, solid-state polarized IR-spectroscopy of oriented colloids in a nematic host, HPLC with tandem mass spectrometry (HPLC ESI-MSMS), and TGV and DSC methods. The compound crystallizes in the monoclinic P2(1)/c space group and its structure consists of a 3D network of molecules joined by intermolecular interactions with the participation of cations, anions and two solvent molecules. The tyrammonium cation adopts a T trans configuration with corresponding angles of phi (1) = 76.0(4) degrees, phi (2 )= 54.8(1) degrees and phi (3) = 63.4(1) degrees, respectively. In the 4-nitrophthalate anion, the COO(-) and COOH groups are turned off the plane of the benzene ring at angles of tau (1) = 88.1(5) degrees and tau (2)= 22.1(7) degrees, respectively.


Assuntos
Ácidos Ftálicos/química , Compostos de Amônio Quaternário/química , Tirosina/análogos & derivados , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Espectrofotometria Infravermelho , Tirosina/química
6.
Amino Acids ; 37(4): 693-701, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18953632

RESUMO

The hydrogensquarate [LeuNH(2)] (HSq) of L-leucinamide has been synthesized and its structure has been determined by single crystal X-ray diffraction. A three dimensional network is formed by hydrogen bonds with participation of the O=C-NH(2) function, the hydrogensquarate ion and the N(+)H(3) group [NH(2)...O=C((Sq)) (2.840 and 2.749 A), ((Sq))OH...O=C(NH(2)) (2.618 A), NH(3) (+)...O=C((Sq)) (3.246, 2.804 and 2.823 A)], respectively. A theoretical approximation of the electronic structure was carried out by means of ab initio UMP2 and MP2 level of theory at the 6-311++G** basis set. The IR-spectroscopic assignment in the solid-phase was obtained by linear-polarized IR-spectroscopy of oriented samples as colloid suspensions in a nematic host and application of the reducing-difference procedure for the interpretation of polarized IR-spectra.


Assuntos
Ciclobutanos/síntese química , Leucina/análogos & derivados , Cristalização , Ciclobutanos/química , Ligação de Hidrogênio , Leucina/síntese química , Leucina/química , Estrutura Molecular , Difração de Raios X
7.
Artigo em Inglês | MEDLINE | ID: mdl-19101193

RESUMO

We report the synthesis, spectroscopic and structural elucidation of two prolinamide derivatives of squaric acid, i.e. prolinamide ester amide of squaric acid ethyl ester (1) and prolinamide diamide of squaric acid dihydrate (2). Both compounds crystallize in non-centrosymmetric space groups, monoclinic P2(1) (1) and orthorhombic P2(1)2(1)2(1) (2), respectively. For first time in the literature the crystal structure of homodiamide of amino acid amide of squaric acid is reported. The data for heterodiamides is also absent. Supramolecular zig-zag chains by hydrogen bonds of H(2)N-C=O ..., HNH (3.020 A) and HNH ..., OC((S(q))) (2.972 A) types with the participation of amide and squaric acid (S(q)) fragments, -CO=NH(2) and O=C((S(q))) are refined in (1). A helix supramolecular structure is formed in (2) by moderate intermolecular HNH ... O=C(NH(2)) hydrogen bond with length of 2.947A. The two crystallographical non-equivalent water molecules stabilized the helix by interactions of types HOH...OC((Sq)) (2.917A), HOH...O=C(NH(2)) (2.899A), H(2)O...NH(2)(C=O) (2.972A), respectively. Optical and magnetic properties are investigated with a view to explain the correlation structure-properties of the newly synthesized molecules.


Assuntos
Ciclobutanos/química , Diamida/química , Ésteres/química , Prolina/análogos & derivados , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Cristalografia , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Peso Molecular , Prolina/química , Conformação Proteica , Estrutura Secundária de Proteína , Espectrofotometria Infravermelho , Espectrometria de Massas em Tandem , Termogravimetria , Água/química , Difração de Raios X
8.
Amino Acids ; 36(2): 195-201, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18317871

RESUMO

Synthesis, isolation, spectroscopic and structural elucidation of tyrosinamide hydrogensquarate monohydrate (I) is reported on the basis of quantum chemical DFT calculations, vibrational analysis and experimental linear-polarized IR-spectroscopy in solid state. These data are compared with those obtained using single crystal X-ray diffraction, which show that the molecules of (I) in the unit cell formed 3D network through moderate intermolecular (Tyr)OH...O = C(Sq) (2.727 A), O=C-NH2...OH(Tyr) (2.991 A), O=C-NH2...OH(Sq) (2.988 A), O=C-NH2...O=C-NH2 (3.068 A), N+H3...O=C(Sq) (2.737, 2.953, 2.954 A), OH2...O=C(Sq) (2.839 A) and (Sq)OH...OH2 (2.607 A) hydrogen bonds. The relationship between the structure and spectroscopic properties is studied.


Assuntos
Tirosina/análogos & derivados , Cristalização , Cristalografia por Raios X , Estrutura Molecular , Espectrofotometria Infravermelho , Tirosina/síntese química , Tirosina/química
9.
Amino Acids ; 36(2): 185-93, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18317872

RESUMO

The synthesis, isolation, spectroscopic and structural elucidation of sympathomimetic amine, tyramine dihydrogenphosphate are of interest due to its biological activity and the establishing correlation between spectroscopic properties and structure. The complex approach for investigation included single crystal X-ray diffraction, new technique in linear-polarized IR-spectroscopy in solid state and quantum chemical calculations with a view to predict the electronic structure and vibrational data of interacting species in entitled compound, the correlation structure-spectroscopic properties as well as the influence of intermolecular interaction on IR-characteristic bands are carried out.


Assuntos
Simpatomiméticos/química , Tiramina/química , Cristalização , Cristalografia por Raios X , Modelos Químicos , Estrutura Molecular , Espectrofotometria Infravermelho , Simpatomiméticos/síntese química , Tiramina/síntese química
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(2): 695-702, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18343192

RESUMO

A distortion of the aromatic character and stabilization of the imino-form as a result of the protonation of 4-dimethylaminopyridine was established by IR-, UV- and 1H NMR-spectral analysis of 4-diaminopyridinium hydrogensquarate. Quantum chemical calculations were carried out at MP2 and B3LYP levels of theory and a 6-311++G** basis set with a view to determining the changes in geometrical parameters and IR-spectroscopic characteristics resulting from Npy protonation. Linear-dichroic IR-spectroscopy coupled with the orientation techniques of solid samples as liquid crystal suspensions and melted solid polycrystalline films was applied for the identification of the IR-bands, characteristic for the structural fragments of the neutral and imino-form of the pyridine derivative. The spectral results were compared with the structure, obtained by a single crystal X-ray analysis. The salt contains dimmers of hydrogensquarate anions and Npy protonated cations of which the former are stabilized by strong intermolecular OH...O interactions (2.552 angstroms and 143.1(2) degrees). The 4-diaminopyridinium cation interacts with the anion through moderate NH...O bonds (2.729 angstroms and 165.0(0) degrees ). Individual cations are pi-pi stacked with their neighbors at a distance of 3.406 angstroms.


Assuntos
4-Aminopiridina/análogos & derivados , Ciclobutanos/química , Hidrogênio/química , 4-Aminopiridina/química , Cristalização , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Espectrofotometria , Vibração
11.
J Phys Chem A ; 112(13): 2899-905, 2008 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-18281965

RESUMO

The novel hydrogensquarate salt of 4-cyanopyridine was synthesized, and its structure and properties were elucidated in detail spectroscopically, thermally, and structurally, using single-crystal X-ray diffraction, linear-polarized solid-state IR spectroscopy, UV spectroscopy, TGA, DSC, DTA, and positive and negative ESI MS as well as 1H and 13C NMR methods. Quantum chemical methods were used to calculate the electronic structure, vibrational data, and electronic spectra. 4-Cyanopyridinium hydrogensquarate monohydrate crystallizes in the space group P and exhibits a layered structure with molecules linked by intermolecular NH...O(HSq-) (2.651 A) and HOH...O(HSq-) (2.792 and 2.563 A) hydrogen bonds with participation of cations, anions, and the solvent molecule. The formation of stable layers of the type (2HSq-.2H2O)n and the observation of a red color in the solid state is discussed. The optical and magnetic properties were elucidated in comparison to the data for neutral 4-cyanopyridine as well as its four known salts.

12.
J Inorg Biochem ; 102(1): 26-32, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17692921

RESUMO

Mononuclear neutral manganese(II) and cobalt(II) complexes with the antibiotic Sodium Monensin A (Mon-Na, 1b) were synthesized and characterized. The crystal structures of M(Mon-Na)2Cl2.H2O (M=Mn, 2; M=Co, 3) were determined by X-ray crystallography. The complexes crystallize in monoclinic space group C2 with a tetrahedrally coordinated transition metal attached to oxygen atoms of deprotonated carboxyl groups of two Sodium Monensin molecules and two chloride ions. The sodium ion remains in the cavity of the ligand and cannot be replaced by Mn(II) or Co(II). The complexes were additionally characterized by different spectroscopic techniques (UV-Visible, EPR, FAB-MS). A preferable octahedral environment around the transition metal centers is observed in polar solvents while the complexes retain their tetrahedral structure in non-polar media. The antimicrobial activity of 1b, 2 and 3 was tested against Gram(+) and Gram(-) bacteria.


Assuntos
Cobalto/química , Manganês/química , Monensin/síntese química , Monensin/farmacologia , Bacillus cereus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Cristalização , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Monensin/química , Salmonella enteritidis/efeitos dos fármacos , Sarcina/efeitos dos fármacos , Espectrofotometria Infravermelho
13.
J Phys Chem A ; 111(40): 10084-9, 2007 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-17867657

RESUMO

2-amino-4-nitroaniline crystallizes in a noncentrosymmetric space group, which gives it significant potential for second-order nonlinear optical properties (NLO) in the bulk. Crystallographic and linear-polarized IR-spectrocopic data in the solid state unambiguously confirm a quinoide-like structure in the ground state in contrast to UV and theoretical data, which indicate an aromatic one for the excited state. UV-vis spectral elucidations in solutions with different polarities indicate a significant charge-transfer band with shifts of up to 100 nm, corresponding to a large value for the molecular first hyperpolarizability. Calculations of the UV- and IR-spectroscopic properties confirm the stabilization of the quinoide-like structure in the ground state, as well as the theoretically predicted NLO properties at the molecular level and provide a value of beta(tot), which is some 3.6 times higher than the analogous parameter for p-nitroaniline, a classical compound with experimentally confirmed NLO properties.

14.
Acta Crystallogr C ; 62(Pt 5): o299-300, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16679609

RESUMO

Cations and anions of the title compound {systematic name: 1-[4-(aminocarbonyl)butyl]guanidinium bis(hydrogensquarate)}, C6H17N5O2+.2C4HO4(-), are connected into a three-dimensional network by intermolecular N-H...O hydrogen bonds between the L-argininamidium ammonium, amide and guanidinium functions and the hydrogensquarate carbonyl O atoms. The independent hydrogensquarate monoanions are linked into dimers by pairs of O-H...O' hydrogen bonds.


Assuntos
Arginina/análogos & derivados , Ciclobutanos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
15.
Inorg Chem ; 44(6): 2081-8, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15762736

RESUMO

Reaction of chloranilic acid (H2ca) with [Os(bpy)2 Br2] (bpy = 2,2'-bipyridine) affords a dinuclear complex of type [{Os(bpy)2}2 (ca)]2+, isolated as the perchlorate salt. A similar reaction of H2ca with [Os(PPh3)2 (pap)Br2] (pap = 2-(phenylazo)pyridine) affords a dinuclear complex of type [{Os(PPh3)2 (pap)}2 (ca)]2+ (isolated as the perchlorate salt) and a mononuclear complex of type [Os(PPh3)2 (pap)(ca)]. Reaction of H2ca with [Os(PPh3)2(CO)2(HCOO)2] gives a dinuclear complex of type [{Os(PPh3)2(CO)2}2 (r-ca)], where r-ca is the two electron reduced form of the chloranilate ligand. The structures of the [{Os(PPh3)2 (pap)}2 (ca)](ClO4)2, [Os(PPh3)2 (pap)(ca)], and [{Os(PPh3)2(CO)2}2 (r-ca)] complexes have been determined by X-ray crystallography. In the [{Os(bpy)2}2 (ca)]2+ and [{Os(PPh3)2 (pap)}2 (ca)]2+ complexes, the chloranilate dianion is serving as a tetradentate bridging ligand. In the [Os(PPh3)2 (pap)(ca)] complex, the chloranilate dianion is serving as a bidentate chelating ligand. In the [{Os(PPh3)2(CO)2}2 (r-ca)] complex, the reduced form of the chloranilate ligand (r-ca(4-)) is serving as a tetradentate bridging ligand. All the four complexes are diamagnetic and show intense metal-to-ligand charge-transfer transitions in the visible region. The [Os(PPh3)2 (pap)(ca)] complex shows an Os(II)-Os(III) oxidation, followed by an Os(III)-Os(IV) oxidation on the positive side of a standard calomel electrode. The three dinuclear complexes show two successive oxidations on the positive side of SCE. The mixed-valent Os(II)-Os(III) species have been generated in the case of the two chloranilate-bridged complexes by coulometric oxidation of the homovalent Os(II)-Os(II) species. The mixed-valent Os(II)-Os(III) species show intense intervalence charge-transfer transitions in the near-IR region.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA