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1.
Luminescence ; 37(9): 1492-1503, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35817756

RESUMO

Powder samples of Li2 CaGeO4 , Ca2 GeO4 , and Ca5 Ge3 O11 doped by 0.5, 1, 2, 3, 4 and 5 at% Eu3+ relative to the Ca2+ , were prepared using a conventional solid-state synthesis technique. X-ray diffraction (XRD) analyses confirmed obtaining the pure phases at all dopant concentrations. In parallel, single crystals of the three compounds with the experimentally found optimal Eu3+ concentration were grown using a flux method. Structural investigation on the single crystals were done with a special attention to the form of the Ca-O polyhedron, the mean Ca-O distance, the Ca-Ca distance in the structure, the distortion degree of the polyhedron, as well as the Eu-Ca substitution site. The main spectral characteristics were analyzed and several relationships between the structural and spectra features were found. The optimal dopant concentration was 3 at% for Ca2 GeO4 and 4at% for Ca5 Ge3 O11 and Li2 CaGeO4 . Commission Internationale de l'éclairage coordinates of the samples showed emission colours in the red region close to the standard red coordinates and slightly influenced by the active ion concentration. The obtained results showed that europium-doped Li2 CaGeO4 , Ca2 GeO4 , and Ca5 Ge3 O11 could be used as red phosphors.


Assuntos
Európio , Luminescência , Cristalografia por Raios X , Európio/química , Lítio
2.
Pharmaceuticals (Basel) ; 14(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34959731

RESUMO

Here, we describe the synthesis, characterization, and biological activities of a series of 26 new styryl-2(3H)-benzothiazolone analogs of combretastatin-A4 (CA-4). The cytotoxic activities of these compounds were tested in several cell lines (EA.hy926, A549, BEAS-2B, MDA-MB-231, HT-29, MCF-7, and MCF-10A), and the relations between structure and cytotoxicity are discussed. From the series, compound (Z)-3-methyl-6-(3,4,5-trimethoxystyryl)-2(3H)-benzothiazolone (26Z) exhibits the most potent cytotoxic activity (IC50 0.13 ± 0.01 µM) against EA.hy926 cells. 26Z not only inhibits vasculogenesis but also disrupts pre-existing vasculature. 26Z is a microtubule-modulating agent and inhibits a spectrum of angiogenic events in EA.hy926 cells by interfering with endothelial cell invasion, migration, and proliferation. 26Z also shows anti-proliferative activity in CA-4 resistant cells with the following IC50 values: HT-29 (0.008 ± 0.001 µM), MDA-MB-231 (1.35 ± 0.42 µM), and MCF-7 (2.42 ± 0.48 µM). Cell-cycle phase-specific experiments show that 26Z treatment results in G2/M arrest and mitotic spindle multipolarity, suggesting that drug-induced centrosome amplification could promote cell death. Some 26Z-treated adherent cells undergo aberrant cytokinesis, resulting in aneuploidy that perhaps contributes to drug-induced cell death. These data indicate that spindle multipolarity induction by 26Z has an exciting chemotherapeutic potential that merits further investigation.

3.
Inorg Chem ; 60(7): 4563-4568, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33709692

RESUMO

Small-pore iron silicate MS-1 (Minho-Sofia, solid number 1) with a 3D porous system, an analogue of the rare mineral imandrite, has been synthesized and characterized. This material is the lowest framework density iron silicate, one of the most siliceous (Si/Fe = 6) iron silicates, the first iron cyclosilicate achieved at hydrothermal conditions, and the only synthetic iron-based member of the lovozerite mineral group.

4.
Bioorg Chem ; 85: 487-497, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30782563

RESUMO

A series of 60 nitrobenzonitrile analogues of the anti-viral agent MDL-860 were synthesized (50 of which are new) and evaluated for their activity against three types of enteroviruses (coxsackievirus B1, coxsackievirus B3 and poliovirus 1). Among them, six diaryl ethers (20e, 27e, 28e, 29e, 33e and 35e) demonstrated high in vitro activity (SI > 50) towards at least one of the tested viruses and very low cytotoxicity against human cells. Compound 27e possesses the broadest spectrum of activity towards all tested viruses in the same way as MDL-860 does. The most active derivatives (27e, 29e and 35e) against coxsackievirus B1 were tested in vivo in newborn mice experimentally infected with 20 MLD50 of coxsackievirus B1. Compound 29e showed promising in vivo activity (protection index 26% and 4 days lengthening of mean survival time). QSAR analysis of the substituent effects on the in vitro cytotoxicity (CC50) and anti-viral activity of the nitrobenzonitrile derivatives was carried out and adequate QSAR models for the anti-viral activity of the compounds against poliovirus 1 and coxsackievirus B1 were constructed.


Assuntos
Antivirais/farmacologia , Nitrilas/farmacologia , Poliovirus/efeitos dos fármacos , Antivirais/síntese química , Antivirais/química , Linhagem Celular , Cristalografia por Raios X , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrilas/síntese química , Nitrilas/química , Relação Quantitativa Estrutura-Atividade
5.
Bioorg Med Chem Lett ; 27(19): 4540-4543, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28870395

RESUMO

A series of twelve novel compounds, analogues of antiviral agent MDL-860 were synthesized and their antiviral activity was evaluated in vitro against enteroviruses poliovirus 1 (PV1), Coxsackieviruses B1 (CVB1) and Coxsackieviruses B3 (CVB3). Compounds 14, 24 and 25 manifested strong antiviral effects against CVB1 and PV1 (SI values of 405 and 118 for CVB1 and PV1 respectively). In contrast to the wide anti-enteroviral activity of MDL-860, these three compounds were inactive against CVB3. Compounds 14, 24 and 25 along with MDL-860 were tested in vivo in mice infected with CVB1. Marked protective effects of compounds 14 and 24 were established, PI values of 50% and 33.3%, respectively. In addition, almost all of the tested compounds manifested very low toxicity.


Assuntos
Antivirais/farmacologia , Infecções por Enterovirus/tratamento farmacológico , Enterovirus/efeitos dos fármacos , Nitrilas/farmacologia , Animais , Antivirais/síntese química , Antivirais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrilas/síntese química , Nitrilas/química , Relação Estrutura-Atividade
6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): o2152-3, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22091167

RESUMO

The carb-oxy-lic acid mol-ecule of the title compound, C(11)H(20)NO(5)P·0.25CH(2)Cl(2), exists as a zwitterion with the H atom of the phospho-nate group being transferred to the imine N atom. In the asymmetric unit, there are two crystallographically independent acid mol-ecules adopting the same absolute configuration and differing slightly in their geometrical parameters. In each mol-ecule, the imino and carboxyl groups are connected via an intra-molecular N-H⋯O hydrogen bond. Inter-molecular O-H⋯O and N-H⋯O hydrogen bonds induce the formation of layers parallel to the ab plane. The dichloro-methane solvent mol-ecule, with a site occupancy of 0.5, is located between the layers.

7.
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
8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1796, 2008 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-21201775

RESUMO

In the title compound, C(18)H(22)N(2)O(4), the dihedral angle between the pyrrolyl and quinolinyl fragments is 68.97 (2)°. Two non-classical intra-molecular C-H⋯O hydrogen bonds stabilize the mol-ecular geometry. In the crystal structure, mol-ecules form infinite chains via moderate inter-molecular N-H⋯O(CH(3)) hydrogen bonds.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): m1023, 2008 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21203015

RESUMO

The title compound, cis,fac-dichloridotetra-kis(dimethyl sulfoxide)-κ(3)S,κO-ruthenium(II), [RuCl(2)(C(2)H(6)OS)(4)], was obtained from newly synthesized ruthenium complexes of 3-amino-2-chloro-pyridine. The Ru atom has a distorted octa-hedral coordination with two cis-oriented chloride ligands and four dimethyl sulfoxide ligands. Three of the sulfoxide ligands are S-bonded in a fac configuration, while the fourth is O-bonded. The title compound represents a new, and fourth, polymorph of the complex. Two other monoclinic forms and an ortho-rhom-bic modification have been reported previously.

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