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1.
Phys Chem Chem Phys ; 26(9): 7269-7275, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38193864

RESUMO

On the basis of variable-temperature single-crystal X-ray diffraction, rotational energy barrier analysis, variable-temperature/frequency dielectric response, and molecular dynamics simulations, here we report a new crystalline supramolecular rotor (CH3NH3)(18-crown-6)[CuCl3], in which the (H3C-NH3)+ ion functions as a smallest dual-wheel rotator showing bisected rotation dynamics, while the host 18-crown-6 macrocycle behaves as a stator that is not strictly stationary. This study also provides a helpful insight into the dynamics of ubiquitous -CH3/-NH3 groups confined in organic or organic-inorganic hybrid solids.

2.
Phys Chem Chem Phys ; 26(5): 3974-3980, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38221866

RESUMO

On the basis of variable-temperature single-crystal X-ray diffraction, variable-temperature/frequency dielectric analysis, variable-temperature solid-state nuclear magnetic resonance spectroscopy, and molecular dynamics simulations, here we present a new model of crystalline supramolecular rotor (i-PrNHMe2)[CdBr3], where a conformationally flexible near-spherical (i-PrNHMe2)+ cation functions as a rotator and a rod-like anionic coordination polymer {[CdBr3]-}∞ acts as the stator, and the adhesion of them is realized by charge-assisted hydrogen bonds.

3.
Small ; 13(47)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29076648

RESUMO

Metal-organic frameworks (MOFs) are very promising self-sacrificing templates for the large-scale fabrication of new functional materials owing to their versatile functionalities and tunable porosities. Most conventional metal oxide electrodes derived from MOFs are limited by the low abundance of incorporated metal elements. This study reports a new strategy for the synthesis of multicomponent active metal oxides by the pyrolysis of polymetallic MOF precursors. A hollow N-doped carbon-coated ZnO/ZnCo2 O4 /CuCo2 O4 nanohybrid is prepared by the thermal annealing of a polymetallic MOF with ammonium bicarbonate as a pore-forming agent. This is the first report on the rational design and preparation of a hybrid composed of three active metal oxide components originating from MOF precursors. Interestingly, as a lithium-ion battery anode, the developed electrode delivers a reversible capacity of 1742 mAh g-1 after 500 cycles at a current density of 0.3 mA g-1 . Furthermore, the material shows large storage capacities (1009 and 667 mAh g-1 ), even at high current flow (3 and 10 A g-1 ). The remarkable high-rate capability and outstanding long-life cycling stability of the multidoped metal oxide benefits from the carbon-coated integrated nanostructure with a hollow interior and the three active metal oxide components.

4.
Photochem Photobiol Sci ; 12(9): 1700-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23788125

RESUMO

A new organic-lanthanide framework [TbL1.5(H2O)2]·H2O (1) [H2L = 5-(3'-carboxylphenyl)nicotinic acid] was synthesized. Its structure was determined by single crystal X-ray diffraction. The complex was characterized by PXRD, FT-IR, fluorescence as well as TGA, and features a 3D framework with a 1D channel and exhibits exceptionally high thermal stability up to 440 °C in air. Furthermore, it displays highly sensitive and selective luminescence quenching to Hg(2+) in aqueous solution. The result of a reversible sensing experiment showed complex 1 could be reusable at least 5 times.

5.
J Phys Chem Lett ; 14(36): 8009-8015, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37651131

RESUMO

Free accessible confined space and loose interaction are crucial for most solid-state ionic motions. Here, by using a near-spherical anion and a disc-shaped ammonium as two distinct but rigid building blocks, we report a new ionic crystal, (HMIm)3[La(NO3)6] (HMIm = 1-methyl-1H-imidazol-3-ium), in which the different confined spaces of three (HMIm)+ ions are fine-tuned over a broad temperature range. This effect can be utilized to modulate the dipolar polarization across a wide temperature/frequency range. Additionally, small-scale substitution of (HMIm)+ by its isomer of almost identical shape/size affords molecular solid solutions, which can further tune the dipolar polarization by varying the doping ratio. It is revealed that the differences in dipole moment and hydrogen bond rather than that of shape/size lead to a distorted crystalline environment for these solid solutions. Overall, we provide an exceptional model for understanding and regulating the dipole motion of polar aromatic molecules/ions in a crystalline environment.

6.
Photochem Photobiol Sci ; 10(11): 1760-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21879139

RESUMO

The first complex picosecond filament, namely a filament of terbium(III) p-hydroxybenzoate, is observed. The filament is the only example of Ln(III) ion two-photon absorption in a complex. A transparent, colorless and mechanically robust thin film, as well as a supramolecular gel, of this complex are prepared in a facile manner and exhibit strong luminescence. The thin film is characterized in detail by XRD, SEM, UV-vis, luminescence spectroscopy and lifetime.


Assuntos
Complexos de Coordenação/química , Géis/química , Térbio/química , Complexos de Coordenação/síntese química , Parabenos/química , Teoria Quântica , Espectrometria de Fluorescência , Fatores de Tempo , Difração de Raios X
7.
Biometals ; 23(4): 739-52, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20422275

RESUMO

A new ligand DBHIP and its two ruthenium(II) complexes [Ru(dmb)(2)(DBHIP)](ClO(4))(2) (1) and [Ru(dmp)(2)(DBHIP)](ClO(4))(2) (2) have been synthesized and characterized. The cytotoxicity of DBHIP and complexes 1 and 2 has been assessed by MTT assay. The apoptosis studies were carried out with acridine orange/ethidium bromide (AO/EB) staining methods. The binding behaviors of these complexes to calf thymus DNA (CT-DNA) were studied by absorption titration, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants of complexes 1 and 2 were determined to be 8.64 +/- 0.16 x 10(4) (s = 1.34) and 2.79 +/- 0.21 x 10(4) (s = 2.17) M(-1). The results suggest that these complexes interact with DNA through intercalative mode. The studies on the mechanism of photocleavage demonstrate that superoxide anion radical (O(2)(*-)) and singlet oxygen ((1)O(2)) may play an important role in the DNA cleavage. The experiments on antioxidant activity show that these compounds also exhibit good antioxidant activity against hydroxyl radical (OH*).


Assuntos
Antioxidantes , Apoptose/efeitos dos fármacos , DNA/efeitos dos fármacos , DNA/metabolismo , Fenantrolinas/química , Compostos de Rutênio , Animais , Antioxidantes/síntese química , Antioxidantes/química , Antioxidantes/farmacologia , Bovinos , Linhagem Celular , DNA/química , Clivagem do DNA/efeitos dos fármacos , Ligantes , Estrutura Molecular , Desnaturação de Ácido Nucleico , Compostos de Rutênio/síntese química , Compostos de Rutênio/química , Compostos de Rutênio/farmacologia , Viscosidade
8.
Chem Biodivers ; 7(7): 1770-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20658665

RESUMO

Many ruthenium(II) complexes show high antitumor activities, and the in vitro antitumor activities are usually related to DNA binding. We designed and synthesized two Ru(II) polypyridyl complexes, [Ru(dmp)2(fpp)]2+ (dmp=2,9-dimethyl-1,10-phenanthroline; fpp=2-[3,4-(difluoromethylenedioxy)phenyl]imidazo[4,5-f] [1,10]phenanthroline and [Ru(phen)(2)(fpp)]2+ (phen=1,10-phenanthroline). The DNA-binding properties of these complexes have been investigated by spectroscopic titration, DNA melting experiments, viscosity measurements, and photoactivated cleavage. The mechanism studies of photocleavage revealed that singlet oxygen (1O2) and superoxide anion radical (O2(.-)) may play an important role in the photocleavage. The cytotoxicity of complexes 1 and 2 have been evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) method; complex 2 shows slightly higher anticancer potency than 1 does against all the cell lines screened.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , DNA/metabolismo , Neoplasias/tratamento farmacológico , Compostos de Rutênio/química , Compostos de Rutênio/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Modelos Moleculares , Estrutura Molecular , Desnaturação de Ácido Nucleico/efeitos dos fármacos , Fenantrolinas/síntese química , Fenantrolinas/química , Fenantrolinas/farmacologia , Processos Fotoquímicos/efeitos dos fármacos , Compostos de Rutênio/síntese química , Viscosidade/efeitos dos fármacos
9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 2): m211, 2010 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21579673

RESUMO

The title compound, [Ru(C(14)H(12)N(2))(2)(C(18)H(14)N(4))](ClO(4))(2)·2H(2)O, consists of an Ru(II) complex cation, two perchlorate anions and two uncoordinated water mol-ecules. The Ru(II) ion is chelated by a 10,11,12,13-tetra-hydro-dipyrido[3,2-a:2',3'-c]phenazine ligand and two 2,9-dimethyl-1,10-phenanthroline ligands in a distorted octa-hedral geometry. The two uncoord-inated water mol-ecules are disordered over five positions, with an occupancy factor of about 0.4 for each site. A supra-molecular structure is formed by weak π-π inter-actions between neighbouring mol-ecules, with centroid-centroid distances of 3.618 (2) and 3.749 (2) Å.

10.
Data Brief ; 17: 689-697, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29556517

RESUMO

In this data article, we present the structural and PARD data of the Ln-MOFs. Detailed structure, luminescence and sensing properties were discussed in our previous study (Zeng et al., in press) [1] The data includes the SBU structure patterns of these Ln-MOFs, thermostability of Ln-MOFs in water and also detailed structure information listed in Table 1, Table 2, Table 3, Table 4, Table 5, Table 6, Table 7, Table 8.

11.
Data Brief ; 20: 1453-1461, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30258949

RESUMO

In this data article, we report the structure, Fourier transform infrared spectroscopy(FT-IR), powder X-ray diffraction (PARD), luminescence decay, thermogravimetric analysis (TGA) and UV-vis data of three series Ln-MOFs. Detailed structure and luminescence properties were discussed in our previous study (Zhao et al., 2018) [1]. The data includes the structure patterns of ligand H2ADA, FT-IR, PXRD and thermostability of Ln-MOFs in the air, detailed structure information for these structures are listed in Table 1, Table 2, Table 3, Table 4, Table 5, Table 6, Table 7.

12.
J Nanosci Nanotechnol ; 16(4): 3705-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27451693

RESUMO

Homogeneously doped Yb3+ and Er3+ cerium-based coordination polymer (CP) microspheres have been successfully synthesized on a large scale through a simple solvothermal route with 2,5-pyridinedicarboxylic acid (2,5-H2PDC) as the organic linker. CeO2: Yb3+, Er3+ porous microspheres were obtained by annealing the corresponding CP microspheres at 600 °C for 4 h under atmospheric pressure. These as-prepared products were characterized by Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersion X-ray (EDX) spectroscopy, Thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis. The room temperature upconversion luminescent spectra of the as-prepared microspheres were carried out by 980 nm NIR light excitation. Interestingly, Yb3+ and Er3+ codoped CP microspheres give a single-band emission centered at 673 nm, while the CeO2: Yb3+, Er3+ microspheres give emission in green and red region, with red being the dominant emission. The emission intensity of the CeO2: Yb3+, Er3+ microspheres were much stronger than that of the Yb3+ and Er3+ codoped CP microspheres.

13.
Photochem Photobiol ; 91(4): 814-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25892403

RESUMO

A new hybrid membrane was prepared by a facile method based on a highly luminescent lanthanide coordination polymer and agarose. The soft membrane was characterized by FT-IR, PXRD, SEM and luminescence. It is found that the soft membrane is a highly selective and sensitive sensor, among 19 metal ion solutions of Fe(3+), Mg(2+), Li(+), Ca(2+), Zn(2+), Cu(2+), Ba(2+), Mn(2+), Ru(3+), Cr(3+), Ag(+), Sr(2+), Cd(2+), Na(+), Ni(2+), Pb(2+), Fe(2+), Hg(2+) and Ca(2+), only Fe(3+) quench the luminescence. The sensing results can be distinguished by the naked eye in daylight or by irradiation of a portable UV light at the scene. Mechanism studies reveal the sensing is due to the decomposition of the coordination polymer 1 which induced by slow permeation of Fe(3+). Further studies found anions of BO3(-), CO3(2-), H2PO4(-), Br(-), Cl(-), ClO4(-), H2PO4(-), I(-), IO3(-) and NO3(-) will not quench the luminescence of the hybrid membrane, which imply that other anions in water would not disturb the detection result.

14.
Dalton Trans ; 42(6): 2052-61, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23178258

RESUMO

A "basophilic method" for phenolic hydroxyl bridged lanthanide coordination polymers (CPs) was developed. With this method, eleven CPs with the general formula of [Ln(HL1)L1·H(2)O](n) (Ln = Tb (1), Nd (2), Eu (3), Gd (4), La (5), Er (6), Y (7), H(2)L1 = 4-methyl salicylic acid) and [Ln(HL2)L2·2MeOH](n) (Ln = Eu (8), Tb (9), Gd (10), La (11), H(2)L2 = 3-hydroxy-2-naphthoic acid) were synthesized based on two ligands, and five of them (1-4 and 8) were characterised by X-ray single crystal diffraction. The powder X-ray diffraction patterns (PXRD) of complexes showed that 1-7 are isostructural, 8-11 are isostructural. Furthermore, 1 was characterised by Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), elemental analysis (EA), one and two photon luminescence were investigated in detail.


Assuntos
Complexos de Coordenação/química , Elementos da Série dos Lantanídeos/química , Fenóis/química , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Ligantes , Medições Luminescentes , Conformação Molecular , Fótons
15.
Photochem Photobiol ; 88(4): 860-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22364355

RESUMO

A new dinuclear terbium complex [Tb(2)(4-msal)(6)(H(2)O)(4)]·6H(2)O (1) (4-msal = 4-methylsalcylate) was synthesized. Its structure was determined by single crystal X-ray diffraction, and the complex was characterized by PXRD, FT-IR, fluorescence, TGA and DTA. Complex 1 exists as discrete molecules that are linked by extensive O-H … O hydrogen bonds into a 3D network. The luminescence lifetimes of 3 µM methanol solution and solid sample of 1 are 1.321 and 1.009 ms, respectively. The quantum yield of solid sample is 6.0%. The luminescence quenched more than 50% when 3% (vol/vol) different impurities (acetone, acetonitrile, chloroform, dichloromethane, dioxane, DMF, DMSO, ethanol, ether, ethyl acetate, glycol, H(2)O, hexane, TEA, THF and toluene or their mixture) were added. The inverse linear relationship between the Lg value of fluorescence intensity and the volume ratio of the minor component (to a maximum of 20%) is interpreted in terms of LgI = a-bX (I: luminescence intensity; X: volume ratio of impurities in methanol; a, b are constants). So 1 is a potential luminescent sensor for analyzing the purity of methanol.

16.
Eur J Med Chem ; 45(2): 564-71, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19932529

RESUMO

Two new ligands maip (1a), paip (1b) with their ruthenium (II) complexes [Ru(bpy)(2)(maip)](ClO(4))(2) (2a) and [Ru(bpy)(2)(paip)](ClO(4))(2) (2b) have been synthesized and characterized. The results show that complexes 2a and 2b interact with DNA through intercalative mode. The cytotoxicity of these compounds has been evaluated by MTT assay. The experiments on antioxidant activity show that these compounds exhibit good antioxidant activity against hydroxyl radical (OH).


Assuntos
DNA/metabolismo , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/metabolismo , Compostos Organometálicos/síntese química , Compostos Organometálicos/metabolismo , Processos Fotoquímicos , Piridinas/química , Rutênio/química , Absorção , Animais , Bovinos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Elétrons , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/toxicidade , Humanos , Radical Hidroxila/química , Desnaturação de Ácido Nucleico , Compostos Organometálicos/farmacologia , Compostos Organometálicos/toxicidade , Ratos , Análise Espectral , Temperatura de Transição , Viscosidade
17.
DNA Cell Biol ; 29(5): 261-70, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20307189

RESUMO

Two new ligands maip (1) (maip = 2-(3-aminophenyl)imizado[4,5-f][1,10]phenanthroline), paip (2) (paip = 2-(4-aminophenyl)imidazo[4,5-f][1,10]phenanthroline), and their ruthenium (II) complexes [Ru(phen)(2)(maip)](ClO(4))(2) (3) and [Ru(phen)(2)(paip)](ClO(4))(2) (4) (phen = 1,10-phenanthroline) have been synthesized and characterized. The cytotoxicity of these compounds was evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The apoptosis assay was carried out with acridine orange/ethidium bromide staining methods. The DNA-binding behaviors of complexes 3 and 4 were investigated by viscosity measurements, thermal denaturation, photocleavage, and spectroscopic methods. The results show that the two complexes intercalate into the base pairs of DNA. In the presence of a complex, apoptosis of BEL-7402 cells was observed. Experiments show that these compounds exhibit antioxidant activity against hydroxyl radicals.


Assuntos
DNA/metabolismo , Substâncias Intercalantes/toxicidade , Rutênio/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Substâncias Intercalantes/química , Substâncias Intercalantes/metabolismo , Fenantrolinas/síntese química , Fenantrolinas/química , Fenantrolinas/toxicidade , Rutênio/química , Rutênio/metabolismo , Viscosidade
18.
Eur J Med Chem ; 45(7): 3087-95, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20417586

RESUMO

A new ligand DBHIP and its two ruthenium (II) complexes [Ru(bpy)(2)(DBHIP)](ClO(4))(2) (1) and [Ru(phen)(2)(DBHIP)](ClO(4))(2) (2) have been synthesized and characterized. The binding behaviors of the two complexes to calf thymus DNA were investigated by absorption spectra, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants for complexes 1 and 2 have been determined to be 8.87+/-0.27 x 10(4)M(-1) (s=1.83) and 1.32+/-0.31 x 10(5)M(-1) (s=1.84). The results suggest that these complexes interact with DNA through intercalative mode. The cytotoxicity of DBHIP, complexes 1 and 2 has been evaluated by MTT assay. The apoptosis assay was carried out with acridine orange/ethidium bromide (AO/EB) staining methods. The studies on the mechanism of photocleavage demonstrate that superoxide anion radical (O(2)(-)) and singlet oxygen ((1)O(2)) may play an important role.


Assuntos
Apoptose/efeitos dos fármacos , DNA/metabolismo , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Compostos Organometálicos/metabolismo , Compostos Organometálicos/farmacologia , Rutênio/química , Absorção , Animais , Bovinos , Linhagem Celular Tumoral , DNA/química , Elétrons , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/química , Humanos , Radical Hidroxila/química , Concentração Inibidora 50 , Medições Luminescentes , Desnaturação de Ácido Nucleico , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Fenantrolinas/química , Processos Fotoquímicos , Plasmídeos/genética , Temperatura de Transição , Viscosidade
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