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1.
Nat Commun ; 12(1): 4966, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404784

RESUMO

Although chirality is an ever-present characteristic in biology and some artificial molecules, controlling the chirality and demystifying the chirality origin of complex assemblies remain challenging. Herein, we report two homochiral Ag14 nanoclusters with inherent chirality originated from identical rotation of six square faces on a Ag8 cube driven by intra-cluster π···π stacking interaction between pntp- (Hpntp = p-nitrothiophenol) ligands. The spontaneous resolution of the racemic (SD/rac-Ag14a) to homochiral nanoclusters (SD/L-Ag14 and SD/R-Ag14) can be realized by re-crystallizing SD/rac-Ag14a in acetonitrile, which promotes the homochiral crystallization in solid state by forming C-H···O/N hydrogen bonds with nitro oxygen atoms in pntp- or aromatic hydrogen atoms in dpph (dpph = 1,6-bis(diphenylphosphino)hexane) on Ag14 nanocluster. This work not only provides strategic guidance for the syntheses of chiral silver nanoclusters in an all-achiral environment, but also deciphers the origin of chirality at molecular level by identifying the special effects of intra- and inter-cluster supramolecular interactions.


Assuntos
Cristalização , Compostos Organometálicos/química , Fenômenos Físicos , Prata/química , Acetonitrilas/química , Cristalografia por Raios X , Hexanos , Hidrogênio , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Oxigênio , Rotação
2.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445489

RESUMO

An original synthetic route was developed for the preparation of previously unknown unsaturated polyaromatic macrolactones containing a 1Z,5Z-diene moiety in 48-71% yields and with >98% stereoselectivity. The method is based on intermolecular cyclocondensation of aromatic dicarboxylic acids with α,ω-alka-nZ,(n+4)Z-dienediols (1,12-dodeca-4Z,8Z-dienediol, 1,14-tetradeca-5Z,9Z-dienediol, 1,18-octadeca-7Z,11Z-dienediol) mediated by N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC)/4-dimethylaminopyridine (DMAP). The unsaturated diols were prepared by successive homo-cyclomagnesiation of tetrahydropyran ethers of O-containing 1,2-dienes with EtMgBr in the presence of Mg metal and the Cp2TiCl2 catalyst (10 mol.%) and subsequent treatment with 0.1 equiv. of para-toluenesulfonic acid of pyran ethers formed after the acid hydrolysis of magnesacyclopentanes. The resulting cyclophanes exhibited high cytotoxic activity in vitro against Jurkat, K562, U937, and HL60 cancer lines. Additionally, the synthesized products were studied for their effect on mitochondria, ability to induce apoptosis, and influence on the cell cycle using modern flow cytometry methods.


Assuntos
Antineoplásicos/síntese química , Éteres Cíclicos/síntese química , Compostos Organometálicos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reação de Cicloadição , Éteres Cíclicos/química , Éteres Cíclicos/farmacologia , Citometria de Fluxo , Células HL-60 , Humanos , Células Jurkat , Células K562 , Estrutura Molecular
3.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445497

RESUMO

Membrane proteins responsible for transporting magnetic resonance (MR) and fluorescent contrast agents are of particular importance because they are potential reporter proteins in noninvasive molecular imaging. Gadobenate dimeglumine (Gd-BOPTA), a liver-specific MR contrast agent, has been used globally for more than 10 years. However, the corresponding molecular transportation mechanism has not been validated. We previously reported that the organic anion transporting polypeptide (OATP) 1B3 has an uptake capability for both MR agents (Gd-EOB-DTPA) and indocyanine green (ICG), a clinically available near-infrared (NIR) fluorescent dye. This study further evaluated OATP1B1, another polypeptide of the OATP family, to determine its reporter capability. In the OATP1B1 transfected 293T transient expression model, both Gd-BOPTA and Gd-EOB-DTPA uptake were confirmed through 1.5 T MR imaging. In the constant OAPT1B1 and OATP1B3 expression model in the HT-1080 cell line, both HT-1080-OAPT1B1 and HT-1080-OATP1B3 were observed to ingest Gd-BOPTA and Gd-EOB-DTPA. Lastly, we validated the ICG uptake capability of both OATP1B1 and OATP1B3. OAPT1B3 exhibited a superior ICG uptake capability to that of OAPT1B1. We conclude that OATP1B1 is a potential reporter for dual MR and NIR fluorescent molecular imaging, especially in conjunction with Gd-BOPTA.


Assuntos
Gadolínio DTPA/química , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Meglumina/análogos & derivados , Imagem Óptica/métodos , Compostos Organometálicos/química , Genes Reporter , Células HEK293 , Humanos , Transportador 1 de Ânion Orgânico Específico do Fígado/química , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Imageamento por Ressonância Magnética , Meglumina/química , Imagem Molecular , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/química , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/genética , Membro 1B3 da Família de Transportadores de Ânion Orgânico Carreador de Soluto/metabolismo
4.
Viruses ; 13(8)2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34452480

RESUMO

We compared the electrostatic properties of the spike proteins (S-proteins) of three coronaviruses, SARS-CoV, MERS-CoV, and SARS-CoV-2, and their interactions with photosensitizers (PSs), octacationic octakis(cholinyl)zinc phthalocyanine (Zn-PcChol8+) and monocationic methylene blue (MB). We found a major common PS binding site at the connection of the S-protein stalk and head. The molecules of Zn-PcChol8+ and MB also form electrostatic encounter complexes with large area of negative electrostatic potential at the head of the S-protein of SARS-CoV-2, between fusion protein and heptad repeat 1 domain. The top of the SARS-CoV spike head demonstrates a notable area of electrostatic contacts with Zn-PcChol8+ and MB that corresponds to the N-terminal domain. The S-protein protomers of SARS-CoV-2 in "open" and "closed" conformations demonstrate different ability to attract PS molecules. In contrast with Zn-PcChol8+, MB possesses the ability to penetrate inside the pocket formed as a result of SARS-CoV-2 receptor binding domain transition into the "open" state. The existence of binding site for cationic PSs common to the S-proteins of SARS-CoV, SARS-CoV-2, and MERS-CoV creates prospects for the wide use of this type of PSs to combat the spread of coronaviruses.


Assuntos
Indóis/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/química , Compostos Organometálicos/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Sítios de Ligação , Indóis/química , Azul de Metileno/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Compostos Organometálicos/química , Conformação Proteica , Domínios Proteicos , Subunidades Proteicas/química , Vírus da SARS/química , SARS-CoV-2/química , Glicoproteína da Espícula de Coronavírus/química , Eletricidade Estática
5.
ACS Appl Mater Interfaces ; 13(33): 39042-39054, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34375073

RESUMO

In developing a cluster-nanocarrier design, as a magnetic resonance imaging contrast agent, we have investigated the enhanced relaxivity of a manganese and iron-oxo cluster grafted within a porous polystyrene nanobead with increased relaxivity due to a higher surface area. The synthesis of the cluster-nanocarrier for the cluster Mn8Fe4O12(O2CC6H4CH═CH2)16(H2O)4, cross-linked with polystyrene (the nanocarrier), under miniemulsion conditions is described. By including a branched hydrophobe, iso-octane, the resulting nanobeads are porous and ∼70 nm in diameter. The increased surface area of the nanobeads compared to nonporous nanobeads leads to an enhancement in relaxivity; r1 increases from 3.8 to 5.2 ± 0.1 mM-1 s-1, and r2 increases from 11.9 to 50.1 ± 4.8 mM-1 s-1, at 9.4 teslas, strengthening the potential for T1 and T2 imaging. Several metrics were used to assess stability, and the porosity produced no reduction in metal stability. Synchrotron X-ray fluorescence microscopy was used to demonstrate that the nanobeads remain intact in vivo. In depth, physicochemical characteristics were determined, including extensive pharmacokinetics, in vivo imaging, and systemic biodistribution analysis.


Assuntos
Materiais Biocompatíveis/química , Meios de Contraste/química , Ferro/química , Manganês/química , Nanopartículas/química , Compostos Organometálicos/química , Poliestirenos/química , Animais , Materiais Biocompatíveis/farmacocinética , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/farmacocinética , Reagentes para Ligações Cruzadas/química , Humanos , Imageamento por Ressonância Magnética , Camundongos Endogâmicos BALB C , Imagem Multimodal , Porosidade , Espectrometria por Raios X , Distribuição Tecidual
6.
Int J Mol Sci ; 22(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206862

RESUMO

We report an ultra-high vacuum low-temperature scanning tunneling microscopy (STM) study of the C60 monolayer grown on Cd(0001). Individual C60 molecules adsorbed on Cd(0001) may exhibit a bright or dim contrast in STM images. When deposited at low temperatures close to 100 K, C60 thin films present a curved structure to release strain due to dominant molecule-substrate interactions. Moreover, edge dislocation appears when two different wavy structures encounter each other, which has seldomly been observed in molecular self-assembly. When growth temperature rose, we found two forms of symmetric kagome lattice superstructures, 2 × 2 and 4 × 4, at room temperature (RT) and 310 K, respectively. The results provide new insight into the growth behavior of C60 films.


Assuntos
Microscopia de Tunelamento/métodos , Compostos Organometálicos/química , Cristalização , Polimerização , Estresse Mecânico , Temperatura , Vácuo
7.
Int J Mol Sci ; 22(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205199

RESUMO

Lead detection for biological environments, aqueous resources, and medicinal compounds, rely mainly on either utilizing bulky lab equipment such as ICP-OES or ready-made sensors, which are based on colorimetry with some limitations including selectivity and low interference. Remote, rapid and efficient detection of heavy metals in aqueous solutions at ppm and sub-ppm levels have faced significant challenges that requires novel compounds with such ability. Here, a UiO-66(Zr) metal-organic framework (MOF) functionalized with SO3H group (SO3H-UiO-66(Zr)) is deposited on the end-face of an optical fiber to detect lead cations (Pb2+) in water at 25.2, 43.5 and 64.0 ppm levels. The SO3H-UiO-66(Zr) system provides a Fabry-Perot sensor by which the lead ions are detected rapidly (milliseconds) at 25.2 ppm aqueous solution reflecting in the wavelength shifts in interference spectrum. The proposed removal mechanism is based on the adsorption of [Pb(OH2)6]2+ in water on SO3H-UiO-66(Zr) due to a strong affinity between functionalized MOF and lead. This is the first work that advances a multi-purpose optical fiber-coated functional MOF as an on-site remote chemical sensor for rapid detection of lead cations at extremely low concentrations in an aqueous system.


Assuntos
Chumbo/isolamento & purificação , Metais Pesados/isolamento & purificação , Compostos Organometálicos/química , Ácidos Ftálicos/química , Poluentes Químicos da Água/isolamento & purificação , Humanos , Chumbo/química , Estruturas Metalorgânicas/química , Metais Pesados/química , Fibras Ópticas , Água/química , Poluentes Químicos da Água/química , Zircônio/química
8.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207182

RESUMO

Globally, cancer is the second (to cardiovascular diseases) leading cause of death. Regardless of various efforts (i.e., finance, research, and workforce) to advance novel cancer theranostics (diagnosis and therapy), there have been few successful attempts towards ongoing clinical treatment options as a result of the complications posed by cancerous tumors. In recent years, the application of magnetic nanomedicine as theranostic devices has garnered enormous attention in cancer treatment research. Magnetic nanoparticles (MNPs) are capable of tuning the magnetic field in their environment, which positively impacts theranostic applications in nanomedicine significantly. MNPs are utilized as contrasting agents for cancer diagnosis, molecular imaging, hyperfusion region visualization, and T cell-based radiotherapy because of their interesting features of small size, high reactive surface area, target ability to cells, and functionalization capability. Radiolabelling of NPs is a powerful diagnostic approach in nuclear medicine imaging and therapy. The use of luminescent radioactive rhenium(I), 188/186Re, tricarbonyl complexes functionalised with magnetite Fe3O4 NPs in nanomedicine has improved the diagnosis and therapy of cancer tumors. This is because the combination of Re(I) with MNPs can improve low distribution and cell penetration into deeper tissues.


Assuntos
Nanopartículas de Magnetita/química , Neoplasias/diagnóstico , Rênio/química , Nanomedicina Teranóstica/métodos , Animais , Humanos , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Compostos Organometálicos/química
9.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209889

RESUMO

Excessive misuse of antibiotics and antimicrobials has led to a spread of microorganisms resistant to most currently used agents. The resulting global threats has driven the search for new materials with optimal antimicrobial activity and their application in various areas of our lives. In our research, we focused on the formation of composite materials produced by the dispersion of titanium(IV)-oxo complexes (TOCs) in poly(ε-caprolactone) (PCL) matrix, which exhibit optimal antimicrobial activity. TOCs, of the general formula [Ti4O2(OiBu)10(O2CR')2] (R' = PhNH2 (1), C13H9 (2)) were synthesized as a result of the direct reaction of titanium(IV) isobutoxide and 4-aminobenzoic acid or 9-fluorenecarboxylic acid. The microcrystalline powders of (1) and (2), whose structures were confirmed by infrared (IR) and Raman spectroscopy, were dispersed in PCL matrixes. In this way, the composites PCL + nTOCs (n = 5 and 20 wt.%) were produced. The structure and physicochemical properties were determined on the basis of Raman microscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), electron paramagnetic resonance spectroscopy (EPR), and UV-Vis diffuse reflectance spectroscopy (DRS). The degree of TOCs distribution in the polymer matrix was monitored by scanning electron microscopy (SEM). The addition of TOCs micro grains into the PCL matrix only slightly changed the thermal and mechanical properties of the composite compared to the pure PCL. Among the investigated PCL + TOCs systems, promising antibacterial properties were confirmed for samples of PCL + n(2) (n = 5, 20 wt.%) composites, which simultaneously revealed the best photocatalytic activity in the visible range.


Assuntos
Anti-Infecciosos/síntese química , Compostos Organometálicos/síntese química , Poliésteres/química , Titânio/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Catálise , Microscopia Eletrônica de Varredura , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Processos Fotoquímicos , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Difração de Raios X
10.
Nat Commun ; 12(1): 4310, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262026

RESUMO

Patients with primary and bone metastatic breast cancer have significantly reduced survival and life quality. Due to the poor drug delivery efficiency of anti-metastasis therapy and the limited response rate of immunotherapy for breast cancer, effective treatment remains a formidable challenge. In this work, engineered macrophages (Oxa(IV)@ZnPc@M) carrying nanomedicine containing oxaliplatin prodrug and photosensitizer are designed as near-infrared (NIR) light-activated drug vectors, aiming to achieve enhanced chemo/photo/immunotherapy of primary and bone metastatic tumors. Oxa(IV)@ZnPc@M exhibits an anti-tumor M1 phenotype polarization and can efficiently home to primary and bone metastatic tumors. Additionally, therapeutics inside Oxa(IV)@ZnPc@M undergo NIR triggered release, which can kill primary tumors via combined chemo-photodynamic therapy and induce immunogenic cell death simultaneously. Oxa(IV)@ZnPc@M combined with anti-PD-L1 can eliminate primary and bone metastatic tumors, activate tumor-specific antitumor immune response, and improve overall survival with limited systemic toxicity. Therefore, this all-in-one macrophage provides a treatment platform for effective therapy of primary and bone metastatic tumors.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Macrófagos/transplante , Fotoquimioterapia/métodos , Animais , Apoptose/efeitos dos fármacos , Antígeno B7-H1/antagonistas & inibidores , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/secundário , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Portadores de Fármacos/química , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Morte Celular Imunogênica/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Indóis/administração & dosagem , Indóis/química , Indóis/farmacologia , Raios Infravermelhos , Macrófagos/química , Nanomedicina , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Oxaliplatina/administração & dosagem , Oxaliplatina/química , Oxaliplatina/farmacologia , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Pró-Fármacos/farmacologia
11.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201878

RESUMO

Composites of metal-organic frameworks and carbon materials have been suggested to be effective materials for the decomposition of chemical warfare agents. In this study, we synthesized UiO-66-NH2/zeolite-templated carbon (ZTC) composites for the adsorption and decomposition of the nerve agents sarin and soman. UiO-66-NH2/ZTC composites with good dispersion were prepared via a solvothermal method. Characterization studies showed that the composites had higher specific surface areas than pristine UiO-66-NH2, with broad pore size distributions centered at 1-2 nm. Owing to their porous nature, the UiO-66-NH2/ZTC composites could adsorb more water at 80% relative humidity. Among the UiO-66-NH2/ZTC composites, U0.8Z0.2 showed the best degradation performance. Characterization and gas adsorption studies revealed that beta-ZTC in U0.8Z0.2 provided additional adsorption and degradation sites for nerve agents. Among the investigated materials, including the pristine materials, U0.8Z0.2 also exhibited the best protection performance against the nerve agents. These results demonstrate that U0.8Z0.2 has the optimal composition for exploiting the degradation performance of pristine UiO-66-NH2 and the adsorption performance of pristine beta-ZTC.


Assuntos
Carbono/química , Estruturas Metalorgânicas/química , Agentes Neurotóxicos/química , Compostos Organometálicos/química , Ácidos Ftálicos/química , Zeolitas/química , Adsorção , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/ultraestrutura , Microscopia Eletrônica de Varredura , Porosidade , Sarina/química , Soman/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X
12.
Inorg Chem ; 60(15): 11081-11089, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34242020

RESUMO

A CuI-TbIII heterometallic MOF, namely 1·DMF, was obtained via a coordination assembly process of isonicotinic acid with CuI and TbIII. 1·DMF can be switched to 1·MeOH in methanol with a luminescent emission response. Meanwhile, 1·MeOH exhibits a reversible single-crystal transformation to 1·DMF after immersion in DMF. Both MOFs have superior physicochemical stability. The 1·DMF-based biosensor has a remarkable sensing performance toward penicillin.


Assuntos
Cobre/química , Luminescência , Compostos Organometálicos/química , Penicilinas/análise , Térbio/química , Teoria da Densidade Funcional , Modelos Moleculares , Conformação Molecular , Penicilinas/química
13.
Photochem Photobiol Sci ; 20(7): 939-953, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34255302

RESUMO

A novel tricationic Zn(II)phthalocyanine derivative, (NCH3)3ZnPc3+, was synthesized by ring expansion reaction of boron(III) [2,9(10),16(17)-trinitrosubphthalocyaninato]chloride. First, the reaction of this subphthalocyanine with 2,3-naphthalenedicarbonitrile and Zn(CH3COO)2 catalyzed by 8-diazabicyclo[5.4.0]undec-7-ene was used to obtain the A3B-type nitrophthalocyanine. After reduction of nitro groups with Na2S and exhaustive methylation of amino groups, (NCH3)3ZnPc3+ was formed in good yields. In addition, the tetracationic analog (NCH3)4ZnPc4+ was synthesized to compare their properties. The absorption and fluorescence spectra showed the Q-bands and the red emission, respectively, which are characteristic of the Zn(II)phthalocyanine derivatives in N,N-dimethylformamide. Furthermore, photodynamic activity sensitized by these compounds was studied in the presence of different molecular probes to sense the formation of reactive oxygen species. (NCH3)3ZnPc3+ efficiently produced singlet molecular oxygen and also it sensitized the formation of superoxide anion radical in the presence of NADH, while the photodynamic activity of (NCH3)4ZnPc4+ was very poor, possibly due to the partial formation of aggregates. Furthermore, the decomposition of L-tryptophan induced by (NCH3)3ZnPc3+ was mainly mediated by a type II mechanism. Antimicrobial photodynamic inactivation sensitized by these phthalocyanines was evaluated in Staphylococcus aureus, Escherichia coli, and Candida albicans, as representative microbial cells. In cell suspensions, (NCH3)3ZnPc3+ was rapidly bound to microbial cells, showing bioimages with red fluorescence emission. After 5 min of irradiation with visible light, (NCH3)3ZnPc3+ was able to completely eliminate S. aureus, E. coli and C. albicans, using 1.0, 2.5 and 5.0 µM phthalocyanine, respectively. In contrast, a low photoinactivation activity was found with (NCH3)4ZnPc4+ as a photosensitizer. Therefore, the amphiphilic tricationic phthalocyanine (NCH3)3ZnPc3+ is a promising photosensitizing structure for application as a broad-spectrum antimicrobial phototherapeutic agent.


Assuntos
Anti-Infecciosos/farmacologia , Indóis/farmacologia , Compostos Organometálicos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Tensoativos/farmacologia , Anti-Infecciosos/química , Candida albicans/efeitos dos fármacos , Cátions/química , Cátions/farmacologia , Escherichia coli/efeitos dos fármacos , Indóis/química , Testes de Sensibilidade Microbiana , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/química
14.
Inorg Chem ; 60(14): 10105-10108, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34232023

RESUMO

An organometallic complex that mimics an amino acid, also known as an amino acid isostere, can be synthesized from a functionalized bipyridine ligand and a fac-[Re(CO)3]+ center. The reaction of an achiral ligand and metal results in a racemic mixture of chiral-at-metal complexes. These metal species have amine and carboxy termini, a side chain type unit that can be varied, as well as the chiral metal that is analogous to the α carbon of an amino acid. The racemic mixtures can be separated into enantiomers by chiral chromatography, and the metal complexes can be incorporated into peptides by using solid-phase peptide synthesis.


Assuntos
Aminoácidos/química , Compostos Organometálicos/química , Ligantes , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
15.
J Photochem Photobiol B ; 222: 112256, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34330080

RESUMO

Photobiomodulation (PBM) is a promising medical treatment modality in the area of photodynamic therapy (PDT). In this study, we investigated the effect of combined therapy in a 3D microenvironment using aluminum chloride phthalocyanines (AlClPc) as the photosensitizing agent. Normal human fibroblast-containing collagen biomatrix was prepared and treated with an oil-in-water (o/a) AlClPc-loaded nanoemulsion (from 0.5 to 3.0 µM) and irradiated at a range of fluences (from 0.1 to 3.0 J/cm2) using a continuous-wave light-emitting diode (LED) irradiation system (660 nm). PBM at 1.2 J/cm2 and AlClPc/NE at 0.5 µM modified the fibroblast signaling response under 3D conditions, promoting collagen synthesis, ROS production, MMP-9 secretion, proliferation of the actin network, and facile myofibroblastic differentiation. PBM alone (at 1.2 J/cm2 and 0.3 J/cm2) had no significant effect on any of these parameters. The combined therapy affected myofibroblastic differentiation, inflammatory response, and extracellular matrix pliability, and should thus be examined further in subsequent studies considering that no side effects of PBM have been reported. Even though significant progress has been made in the field of phototherapy in recent years, it is necessary to further elucidate the detailed mechanisms underlying its effects already shown in 2D conditions to increase the acceptance of this beneficial and non-invasive therapeutic approach.


Assuntos
Cloreto de Alumínio/farmacologia , Fibroblastos/efeitos dos fármacos , Indóis/farmacologia , Luz , Compostos Organometálicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Cloreto de Alumínio/química , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Colágeno/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Indóis/química , Metaloproteinase 9 da Matriz/metabolismo , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo
17.
Inorg Chem ; 60(14): 10186-10198, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34232628

RESUMO

An original example of modular crystal engineering involving molecular magnetic {CuII[WV(CN)8]}- bilayers and adeninium cations (AdeH+) toward the new layered molecular magnet (AdeH){CuII[WV(CN)8]}·2H2O (1) is presented. 1 crystallizes within the monoclinic C2 space group (a = 41.3174(12), b = 7.0727(3), c = 7.3180(2) Å, ß = 93.119(3)°, and V = 2135 Å3). The bilayer topology is based on a stereochemical matching between the square pyramidal shape of CuII moiety and the bicapped trigonal prismatic shape of [WV(µ-CN)5(CN)3], and the separation between bilayers is significantly increased (by ∼50%; from ca. 9.5 to ca. 14.5 Å) compared to several former analogues in this family. This was achieved via a unique combination of (i) a 1D ribbonlike hydrogen bond system {AdeH+···H2O···AdeH+···}∞ exploiting planar water-assisted Hoogsteen···Sugar synthons with (ii) parallel 1D π-π stacks {AdeH+···AdeH+}∞. In-plane 2D XY magnetism is characterized by a Tc close to 33 K, Hc,in-plane = 60 Oe, and Hc,out-of-plane = 750 Oe, high values of in-plane γ critical exponents (γb = 2.34(6) for H||b and γc = 2.16(5) for H||c), and a Berezinskii-Kosterlitz-Thouless (BKT) topological phase transition, deduced from crystal-orientation-dependent scaling analysis. The obtained values of in-plane ν critical exponents, νb = 0.48(5) for H||b and νc = 0.49(3) for H||c, confirm the BKT transition (νBKT = 0.5). Full-range angle-resolved monocrystalline magnetic measurements supported by dedicated calculations indicated the occurrence of nonlinear susceptibility performance within the easy plane in a magnetically ordered state. We refer the occurrence of this phenomenon to spontaneous resolution in the C2 space group, a tandem not observed in studies on previous analogues and rarely reported in the field of molecular materials. The above magneto-supramolecular strategy may provide a novel means for the design of 2D molecular magnetic networks and help to uncover the inherent phenomena.


Assuntos
Adenina/química , Fenômenos Magnéticos , Compostos Organometálicos/química , Cobre/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular
18.
Nat Commun ; 12(1): 3706, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140488

RESUMO

Organometallic complexes are ubiquitous in chemistry and biology. Whereas their preparation has historically relied on ligand synthesis followed by coordination to metal centers, the ability to efficiently diversify their structures remains a synthetic challenge. A promising yet underdeveloped strategy involves the direct manipulation of ligands that are already bound to a metal center, also known as chemistry-on-the-complex. Herein, we introduce a versatile platform for on-the-complex annulation reactions using transient aryne intermediates. In one variant, organometallic complexes undergo transition metal-catalyzed annulations with in situ generated arynes to form up to six new carbon-carbon bonds. In the other variant, an organometallic complex bearing a free aryne is generated and intercepted in cycloaddition reactions to access unique scaffolds. Our studies, centered around privileged polypyridyl metal complexes, provide an effective strategy to annulate organometallic complexes and access complex metal-ligand scaffolds, while furthering the synthetic utility of strained intermediates in chemical synthesis.


Assuntos
Derivados de Benzeno/química , Complexos de Coordenação/química , Metais/química , Compostos Organometálicos/química , Carbono/química , Catálise , Complexos de Coordenação/síntese química , Ligantes , Compostos Organometálicos/síntese química , Paládio/química , Rutênio/química , Elementos de Transição/química
19.
Viruses ; 13(6)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070524

RESUMO

SARS-CoV-2 emerged in 2019 as a devastating viral pathogen with no available preventative or treatment to control what led to the current global pandemic. The continued spread of the virus and increasing death toll necessitate the development of effective antiviral treatments to combat this virus. To this end, we evaluated a new class of organometallic complexes as potential antivirals. Our findings demonstrate that two pentamethylcyclopentadienyl (Cp*) rhodium piano stool complexes, Cp*Rh(1,3-dicyclohexylimidazol-2-ylidene)Cl2 (complex 2) and Cp*Rh(dipivaloylmethanato)Cl (complex 4), have direct virucidal activity against SARS-CoV-2. Subsequent in vitro testing suggests that complex 4 is the more stable and effective complex and demonstrates that both 2 and 4 have low toxicity in Vero E6 and Calu-3 cells. The results presented here highlight the potential application of organometallic complexes as antivirals and support further investigation into their activity.


Assuntos
Antivirais/farmacologia , Compostos Organometálicos/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/química , COVID-19/virologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Compostos Organometálicos/química , SARS-CoV-2/fisiologia , Células Vero , Replicação Viral/efeitos dos fármacos
20.
ACS Appl Mater Interfaces ; 13(26): 31010-31020, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160200

RESUMO

The development of high-performance protein-imprinted materials is vital to meet the requirements of proteomics research but remains a challenge. Herein, a new type of raspberry-like cytochrome C-imprinted nanoparticle was first designed and fabricated via surface imprinting technology combined with a template immobilization strategy. In particular, the state-of-the-art metal-organic framework (MOF)/carbon nanoparticle (CN) composites were selected as protein immobilization carriers for two advantages: (1) the composites reflected the intrinsic characteristics of MOFs including flexible design, facile preparation, and extensive interactions with proteins and (2) the utilization of composites also overcame the issue associated with the severe agglomeration of individual MOFs during the post-use process. Therefore, the as-prepared composites exhibited a regular raspberry-like shape with good dispersion (polydispersity index (PDI) < 0.25), high specific surface area (551.4 m2 g-1), and outstanding cytochrome C immobilization capacity (900 mg g-1). Furthermore, a zwitterionic monomer was chosen to participate in the synthesis of an imprinting layer to reduce the nonspecific binding with proteins. As a result, the unique design presented here in both the protein immobilization carrier and the selected polymer composition endowed the imprinted material (noted as CN@UIO-66@MIPs) with the excellent ability for cytochrome C enrichment with extremely high recognition ability (imprinting factor (IF) = 6.1), rapid adsorption equilibrium time (40 min), and large adsorption capacity (815 mg g-1). Furthermore, encouraged by the experimental results, we successfully used CN@UIO-66@MIPs to specifically capture cytochrome C in mixed protein solutions and biological samples, which proved them to be a potential candidate for protein separation and purification.


Assuntos
Citocromos c/isolamento & purificação , Estruturas Metalorgânicas/química , Polímeros Molecularmente Impressos/química , Nanopartículas/química , Adsorção , Animais , Carbono/química , Fracionamento Químico/métodos , Citocromos c/química , Cinética , Compostos Organometálicos/química , Ácidos Ftálicos/química , Ratos
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