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1.
J Inorg Biochem ; 256: 112573, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38678913

RESUMO

This paper describes the synthesis, structural analysis, as well as the magnetic and spectroscopic characterizations of three new dicopper(II) complexes with dinucleating phenol-based ligands containing different thioether donor substituents: aromatic (1), aliphatic (2) or thiophene (3). Temperature-dependent magnetometry reveals the presence of antiferromagnetic coupling for 1 and 3 (J = -2.27 cm-1 and -5.01 cm-1, respectively, H = -2JS1S2) and ferromagnetic coupling for 2 (J = 5.72 cm-1). Broken symmetry DFT calculations attribute this behavior to a major contribution from the dz2 orbitals for 1 and 3, and from the dx2-y2 orbitals for 2, along with the p orbitals of the oxygens. The bioinspired catalytic activities of these complexes related to catechol oxidase were studied using 3,5-di-tert-butylcatechol as substrate. The order of catalytic rates for the substrate oxidation follows the trend 1 > 2 > 3 with kcat of (90.79 ± 2.90) × 10-3 for 1, (64.21 ± 0.99) × 10-3 for 2 and (14.20 ± 0.32) × 10-3 s-1 for 3. The complexes also cleave DNA through an oxidative mechanism with minor-groove preference, as indicated by experimental and molecular docking assays. Antimicrobial potential of these highly active complexes has shown that 3 inhibits both Staphylococcus aureus bacterium and Epidermophyton floccosum fungus. Notably, the complexes were found to be nontoxic to normal cells but exhibited cytotoxicity against epidermoid carcinoma cells, surpassing the activity of the metallodrug cisplatin. This research shows the multifaceted properties of these complexes, making them promising candidates for various applications in catalysis, nucleic acids research, and antimicrobial activities.


Assuntos
Antineoplásicos , Complexos de Coordenação , Oxirredução , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Ligantes , Sulfetos/química , Sulfetos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Platina/química , Platina/farmacologia , Linhagem Celular Tumoral
2.
J Inorg Biochem ; 241: 112121, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36696836

RESUMO

Five ternary copper(II) complexes, [Cu2(phen)2(L1)(ClO4)2] (1), [Cu2(phen)2(L1)(DMSO)2](PF6)2 (2), [Cu2(bpy)2(L1)(ClO4)2(H2O)2] (3), [Cu2(dmp)2(L1)(ClO4)2(H2O)2] (4), and [Cu(phen)(L2)]2(ClO4)2 (5), in which phen = 1,10-phenanthroline, bpy = 2,2'-bipyridine, dmp = 2,9-dimethyl-1,10-phenanthroline, H2L1 = 1,4-dihydroxyanthracene-9,10-dione and HL2 = 1-hydroxyanthracene-9,10-dione, DMSO = dimethylsulfoxide, were synthesized and fully characterized. Complex 2 was obtained through the substitution of perchlorate for DMSO. When two hydroxyquinone groups are present, L1 makes a bridge between two Cu(II) ions, which also bind two nitrogens of the respective diimine ligand. The compounds bind to calf thymus DNA and oxidatively cleave pUC19 DNA according to the following order of activity 1 > 4-5 > 3. Furthermore, complexes 1, 3, 4 and 5 inhibit topoisomerase-I activity and the growth of myelogenous leukemia cells with the IC50 values of 1.13, 10.60, 0.078, and 1.84 µmol L-1, respectively. Complexes 1 and 4 are the most active in cancer cells and in DNA cleavage.


Assuntos
Cobre , Compostos Heterocíclicos , Cobre/farmacologia , Ligantes , Dimetil Sulfóxido , Ligação Proteica , Cristalografia por Raios X
3.
J Inorg Biochem ; 239: 112087, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36508973

RESUMO

A new cis-dihalo copper(II) complex, [CuII(HLbz)(Cl)2].CH3CN (1), where HLbz = (S)-2-(((2-(2-(pyridin-2-yl)-2H-benzo[e][1,3]oxazin-3(4H)-yl)ethyl)amino)methyl)phenol), was isolated by reacting copper(II) chloride dihydrate and the H2L ligand (H2L = 2,2'-((2-(pyridin-2-yl)imidazolidine-1,3-diyl)bis(methylene))diphenol) in a MeOH/CH3CN (1:3 v/v) mixture. The complex formation occurred via the ligand modification during complexation, producing a unique structure containing 2H-benzo[e][1,3]oxazin, as observed from the single crystal X-ray structure determination. The complex was characterized by elemental analysis, potentiometric titration, spectroscopic techniques (UV-Vis, FT-IR) and conductance measurements. Complex 1 inhibits the growth of myelogenous leukemia cells with an IC50 of 17.3 µmol L-1.


Assuntos
Cobre , Fenóis , Cobre/química , Cristalografia por Raios X , Ligantes , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Inorg Biochem ; 237: 111993, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36108344

RESUMO

This work describes the synthesis, characterization and in vitro anticancer activity of two platinum(II) complexes of the type [Pt(L1)2(1,10-phen)] 1 and [Pt(L2)2(1,10-phen)] 2, where L1 = 5-heptyl-1,3,4-oxadiazole-2-(3H)-thione, L2 = 5-nonyl-1,3,4-oxadiazole-2-(3H)-thione and 1,10-phen = 1,10-phenanthroline. As to the structure of these complexes, the X-ray structural analysis of 1 indicates that the geometry around the platinum(II) ion is distorted square-planar, where two 5-alkyl-1,3,4-oxadiazol-2-thione derivatives coordinate a platinum(II) ion through the sulfur atom. A chelating bidentate phenanthroline molecule completes the coordination sphere. We tested these complexes in two breast cancer cell lines, namely, MCF-7 (a hormone responsive cancer cell) and MDA-MB-231 (triple negative breast cancer cell). In both cells, the most lipophilic platinum compound, complex 2, was more active than cisplatin, one of the most widely used anticancer drugs nowadays. DNA binding studies indicated that such complexes are able to bind to ct-DNA with Kb values of 104 M-1. According to data from dichroism circular and fluorescence spectroscopy, these complexes appear to bind to the DNA in a non-intercalative, probably via minor groove. Molecular docking followed by semiempirical simulations indicated that these complexes showed favorable interactions with the minor groove of the double helix of ct-DNA in an A-T rich region. Thereafter, flow cytometry analysis showed that complex 2 induced apoptosis and necrosis in MCF-7 cells.


Assuntos
Antineoplásicos , Complexos de Coordenação , Humanos , Fenantrolinas/farmacologia , Fenantrolinas/química , Platina/química , Tionas , Simulação de Acoplamento Molecular , Antineoplásicos/química , DNA/química , Complexos de Coordenação/química , Linhagem Celular Tumoral
5.
J Inorg Biochem ; 222: 111522, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34218087

RESUMO

Two new bismuth(III) complexes, [BiL1Cl2] (1) and [BiL2Cl2] (2), in which L1 is (2-hydroxy-4-6-di-tert-butylbenzyl-2-pyridylmethyl)amine and L2 is 2,4-diiodo-6-((pyridine-2-ylmethylamino)methyl)phenol, were synthesized and characterized by elemental and conductivity analyses, atomic absorption spectrometry, infrared and 1H NMR spectroscopies. The molecular structure of 1 reveals that the NN'O ligand forms a 1:1 complex with bismuth through coordination via the nitrogen of the aliphatic amine, the nitrogen of the pyridine ring and the oxygen of the phenolate. The coordination sphere is completed with two chloride anions in a distorted square pyramidal geometry. Bismuth exhibits the same coordination mode in compound 2. The cytotoxic activity of 1 and 2 was investigated in a chronic myelogenous leukemia cell line. The complexes are approximately three times more potent than the corresponding free ligands, with the IC50 values 0.30 and 0.38 µM for complex 1 and 2, respectively. To address the cellular mechanisms underlying cell demise, apoptosis was quantified by flow cytometry analysis. From 0.1 µM, both complexes induce apoptosis and there is a remarkable concentration-dependent increase in the population of cells in apoptosis. The complexes were also evaluated against Gram-positive and Gram-negative bacteria. Both inhibited the bacterial growth in a concentration-dependent way, with remarkable activity in some of the tested strains, for example, complex 2 was more active than its free ligand against all bacterial strains and approximately fourteen times more potent against S. dysenteriae and S. typhimurium.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Antibacterianos/síntese química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bismuto/química , Complexos de Coordenação/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Ligantes , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/síntese química , Fenóis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia
6.
J Inorg Biochem ; 219: 111392, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33752123

RESUMO

Herein, we report the synthesis and characterization of the first two AlIII(µ-OH)MII (M = Zn (1) and Cu (2)) complexes with the unsymmetrical ligand H2L{2-[[(2-hydroxybenzyl)(2-pyridylmethyl)]aminomethyl]-6-bis(pyridylmethyl)aminomethyl}-4-methylphenol. The complexes were characterized through elemental analysis, X-ray crystallography, IR spectroscopy, mass spectrometry and potentiometric titration. In addition, complex 2 was characterized by electronic spectroscopy. Kinetics studies on the hydrolysis of the model substrate bis(2,4-dinitrophenyl)phosphate by 1 and 2 show Michaelis-Menten behavior, with 1 being slightly more active (8.31%) than 2 (at pH 7.0). The antimicrobial effect of the compounds was studied using four bacterial strains (Staphylococcus aureus, Pseudomonas aeuruginosa, Shigella sonnei and Shigella dysenteriae) and for both complexes the inhibition of bacterial growth was superior to that caused by sulfapyridine, but inferior to that of tetracycline. The dark cytotoxicity and photocytotoxicity (under UV-A light) of the complexes in a chronic myelogenous leukemia cell line were investigated. Complexes 1 and 2 exhibited significant cytotoxic activity against K562 cells, which undergoes a 2-fold increase on applying 5 min of irradiation with UV-A light. Complex 2 was more effective and a good correlation between cytotoxicity and intracellular concentration was observed, the intracellular copper concentration required to inhibit 50% of cell growth being 3.5 × 10-15 mol cell-1.


Assuntos
Alumínio/farmacologia , Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Monoéster Fosfórico Hidrolases/metabolismo , Zinco/farmacologia , Alumínio/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Cobre/química , Cristalografia por Raios X/métodos , Humanos , Hidrólise , Células K562 , Cinética , Ligantes , Espectrometria de Massas/métodos , Zinco/química
7.
Molecules ; 24(11)2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31181667

RESUMO

Two new complexes of Ru(II) with mixed ligands were prepared: [Ru(bpy)2smp](PF6) (1) and [Ru(phen)2smp](PF6) (2), in which smp = sulfamethoxypyridazine; bpy = 2,2'-bipyridine; phen = 1,10-phenanthroline. The complexes have been characterized by elemental and conductivity analyses; infrared, NMR, and electrospray ionization mass spectroscopies; and X-ray diffraction of single crystal. Structural analyses reveal a distorted octahedral geometry around Ru(II) that is bound to two bpy (in 1) or two phen (in 2) via their two heterocyclic nitrogens and to two nitrogen atoms from sulfamethoxypyridazine-one of the methoxypyridazine ring and the sulfonamidic nitrogen, which is deprotonated. Both complexes inhibit the growth of chronic myelogenous leukemia cells. The interaction of the complexes with bovine serum albumin and DNA is described. DNA footprinting using an oligonucleotide as substrate showed the complexes' preference for thymine base rich sites. It is worth notifying that the complexes interact with the Src homology SH3 domain of the Abl tyrosine kinase protein. Abl protein is involved in signal transduction and implicated in the development of chronic myelogenous leukemia. Nuclear magnetic resonance (NMR) studies of the interaction of complex 2 with the Abl-SH3 domain showed that the most affected residues were T79, G97, W99, and Y115.


Assuntos
Antineoplásicos/síntese química , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Compostos Organometálicos/síntese química , Rutênio/química , Sulfametoxipiridazina/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Dicroísmo Circular , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Estrutura Molecular , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Proteínas Proto-Oncogênicas c-abl/química , Proteínas Proto-Oncogênicas c-abl/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Difração de Raios X , Domínios de Homologia de src
8.
J Inorg Biochem ; 172: 138-146, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28463762

RESUMO

Five new copper(II) complexes of the type [Cu(NO)(NN)(ClO4)2], in which NO=4-fluorophenoxyacetic acid hydrazide (4-FH) or 4-nitrobenzoic hydrazide (4-NH) and NN=1,10-phenanthroline (phen), 4-4'-dimethoxy-2-2'-bipyridine (dmb) or 2,2-bipyridine (bipy) were synthesized and characterized using various spectroscopic methods. The X-ray structural analysis of one representative compound indicates that the geometry around the copper ion is distorted octahedron, in which the ion is coordinated to hydrazide via the terminal nitrogen and the carbonyl oxygen, and to heterocyclic bases via their two nitrogen atoms. Two perchlorate anions occupy the apical positions, completing the coordination sphere. The cytotoxic activity of compounds was investigated in three tumor cell lines (K562, MDA-MB-231 and MCF-7). Concerning K562 cell line, the complexes with 1,10-phenanthroline exhibit high cytotoxic activity and are more active than carboplatin, free ligands and [Cu(phen)2]2+. Considering the cytotoxicity results, further investigations for the compounds [Cu(4-FH)(phen)(ClO4)2] I and [Cu(4-NH)(phen)(ClO4)2]∙H2O III were performed. Flow cytometric analysis revealed that these complexes induce apoptotic cell death in MDA-MB-231 cell line and bind to DNA with K values of 4.38×104 and 2.62×104, respectively. These compounds were also evaluated against wild type Mycobacterium tuberculosis (ATCC 27294) and exhibited antimycobacterial activity, displayed MIC values lower than those of the corresponding free ligands.


Assuntos
Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Cobre/química , Compostos Heterocíclicos/química , Hidrazinas/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Complexos de Coordenação/química , Cristalografia por Raios X , Feminino , Humanos , Concentração Inibidora 50 , Células K562 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium/efeitos dos fármacos
9.
J Inorg Biochem ; 132: 67-76, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24144484

RESUMO

Four new ternary complexes of copper(II) were synthesized and characterized: [Cu(hyd)(bpy)(acn)(ClO4)](ClO4)] (1), [Cu(hyd)(phen)(acn)(ClO4)](ClO4)] (2), [Cu(Shyd)(bpy)(acn)(ClO4)](ClO4)] (3) and [Cu(Shyd)(phen)(acn)(ClO4)](ClO4)] (4), in which acn=acetonitrile; hyd=2-furoic acid hydrazide, bpy=2,2-bipyridine; phen=1,10-phenanthroline and Shyd=2-thiophenecarboxylic acid hydrazide. The cytotoxic activity of the complexes in a chronic myelogenous leukemia cell line was investigated. All complexes are able to enter cells and inhibit cellular growth in a concentration-dependent manner, with an activity higher than that of the corresponding free ligands. The substitution of Shyd for hyd increases the activity, while the substitution of bpy for phen renders the complex less active. Therefore, the most potent complex is 4 with an IC50 value of 1.5±0.2µM. The intracellular copper concentration needed to inhibit 50% of cell growth is approximately 7×10(-15)mol/cell. It is worth notifying that a correlation between cytotoxic activity, DNA binding affinity and DNA cleavage was found: 1<3<2<4.


Assuntos
Complexos de Coordenação , Cobre/química , Cobre/toxicidade , DNA/química , Compostos Heterocíclicos , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Cristalografia por Raios X , Inibidores do Crescimento/síntese química , Inibidores do Crescimento/química , Inibidores do Crescimento/toxicidade , Compostos Heterocíclicos/química , Compostos Heterocíclicos/toxicidade , Humanos , Ligação de Hidrogênio , Concentração Inibidora 50 , Células K562 , Ligantes , Modelos Moleculares , Nitrogênio/química
10.
Molecules ; 18(2): 1464-76, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23348999

RESUMO

A new complex of Bi(III) and sulfapyridine was synthesized and characterized by elemental analysis, atomic absorption spectrometry, conductivity analysis, electrospray ionization mass spectrometry (ESI-MS), infrared spectroscopy, and single crystal X-ray diffraction methods. The antimicrobial and the cytotoxic activities of the compound were investigated. Elemental and conductivity analyses are in accordance to the formulation [BiCl3(C11H11N3O2S)3]. The structure of the complex reveals a distorted octahedral geometry around the bismuth atom, which is bound to three sulfonamidic nitrogens from sulfapyridine, acting as a monodentate ligand, and to three chloride ions. The presence of the compound in solution was confirmed by ESI-MS studies. The complex is 3 times more potent than the ligand against Salmonella typhimurium, 4 times against Staphylococcus aureus, Shigella dysenteriae, and Shigella sonnei and 8 times more potent against Pseudomonas aeruginosa and Escherichia coli. The compound inhibits the growth of chronic myelogenous leukemia cells with an IC50 value of 44 µM whereas the free ligand has no effect up to 100 µM.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bismuto/química , Bismuto/farmacologia , Sulfapiridina/química , Sulfapiridina/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Células K562 , Testes de Sensibilidade Microbiana , Conformação Molecular
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