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1.
Chem Commun (Camb) ; 53(15): 2394-2397, 2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-28174776

RESUMO

Two Fe-based porous MOFs have been constructed from dimeric Fe-clusters and rod-shaped heterobimetallic {Fe2Na3}n chains as SBUs, respectively. Both of them exhibit highly selective CO2 adsorption over CH4 and N2, owing to their abundant multiple active sites.

2.
Dalton Trans ; 43(45): 16986-91, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25315719

RESUMO

Reaction of Mn(OAc)2·4H2O with the H2L ligand affords a new manganese 22-MC-8 azametallacrown [Mn8(µ3-O)2(µ3-OH)2(µ2-OH)2(L)6(OAc)2(OH2)4]·2DMF (H2L = 3-(2-oxyphenyl)-5-(pyrazin-2-yl)-1,2,4-triazole). The structural analysis of the complex reveals that the azaMC ring possesses -[Mn-O-Mn-N-N-Mn-N-N-Mn-N-N]- connectivity. The magnetic behavior of the complex shows the dominant antiferromagnetic interactions between the manganese ions with S = 4 and the frequency-dependent out-of-phase signal.

3.
Chemistry ; 20(45): 14846-52, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25234745

RESUMO

Three isoreticular hydrogen-bonded frameworks with functionalized pore structures were constructed by a modular self-assembly process in which a series of amino acids with various substituents serve as facile exchange subassemblies to decorate the pore wall. The ordered amino acid side-chain groups in the pore channels play an important role in determining the adsorption behavior of the framework materials, and ensure exclusive adsorption of methanol/water over ethanol. Gas-chromatographic separation experiments demonstrated that alcohols can be efficiently separated from ternary water/methanol/ethanol mixtures and revealed a key influence of the adsorbate-host framework interaction on the practical separation performance of mixtures.

4.
Chemistry ; 18(7): 1924-31, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22267182

RESUMO

A series of metal-organic frameworks based on a flexible, highly charged Bpybc ligand, namely 1⋅Mn⊃OH(-), 2⋅Mn⊃SO(4)(2-), 3⋅Mn⊃bdc(2-), 4⋅Eu⊃SO(4)(2-) (H(2)BpybcCl(2) = 1,1'-bis(4-carboxybenzyl)-4,4'-bipyridinium dichloride, H(2)bdc = 1,4-benzenedicarboxylic acid) have been obtained by a self-assembly process. Single-crystal X-ray-diffraction analysis revealed that all of these compounds contained the same n-fold 2D→3D Borromean-entangled topology with irregular butterfly-like pore channels that were parallel to the Borromean sheets. These structures were highly tolerant towards various metal ions (from divalent transition metals to trivalent lanthanide ions) and anion species (from small inorganic anions to bulky organic anions), which demonstrated the superstability of these Borromean linkages. This non-interpenetrated entanglement represents a new way of increasing the stability of the porous frameworks. The introduction of bipyridinium molecules into the porous frameworks led to the formation of cationic surface, which showed high affinities to methanol and water vapor. The distinct adsorption and desorption isotherms of methanol vapor in four complexes revealed that the accommodated anion species (of different size, shape, and location) provided a unique platform to tune the environment of the pore space. Measurements of the adsorption of various organic vapors onto framework 1⋅Mn⊃OH(-) further revealed that these pores have a high adsorption selectivity towards molecules with different sizes, polarities, or π-conjugated structures.

5.
Chemistry ; 15(44): 11890-7, 2009 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-19780117

RESUMO

A multifunctional pillared-layer porous coordination polymer, {[Mn(2)(Bpybc)(ox)(2)]8 H(2)O}(n), has been constructed based on a flexible viologen derivative, 1,1'-bis(4-carboxybenzyl)-4,4'-bipyridinium dichloride (H(2)BpybcCl(2)), and an oxalate (ox) coligand. Single-crystal X-ray analysis reveals that the compound possesses multichannels with dimensions of about 6.1x6.6 A along the [110] and [-110] directions and 4.2x7.6 A along [100], and a void space of about 41.4 %. Hydrogen adsorption measurements at 77 K and 1 atm indicate that the compound exhibits a hydrogen uptake of 0.71 wt %. Owing to the incorporation of bipyridinium acceptor units, the compound can selectively accommodate aromatic donors into its nanosized pores based on charge-transfer interactions in an elastic way, and afford a specific color to different guests. Furthermore, the effect of perturbation exerted by the guest molecules on its magnetic properties has been investigated. The results indicate that the donor inclusion has little effect on its antiferromagnetic behavior, whereas dehydration of the compound decreases the strength of the magnetic exchange couplings and results in a change of the antiferromagnetic transition temperature from 14.7 to 9.8 K.

6.
Inorg Chem ; 48(4): 1266-8, 2009 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-19166285

RESUMO

A novel coordination compound, {[Cd(BDC)(Bpybc)(1.5)].10H(2)O}(n), obtained by the reaction of CdCl(2) with 1,1'-bis(4-carboxybenzyl)-4,4'-bipyridinium dichloride (H(2)BpybcCl(2)) and 1,4-benzenedicarboxylic acid (H(2)BDC), contains 1D polymeric chains that are comprised of alternating rings and rods and dangling lateral arms. These 1D polymeric motifs are interlaced via rotaxane-like mechanical linkages to give 2D armed-polyrotaxane sheets, which are further mutually polythreaded via pseudorotaxane-like mechanical linkages to form a 3D polypseudorotaxane array. Notably, a sandwich-type donor-acceptor-donor stacking is formed within each ring as a consequence of both types of polythreading in this species, and photoinduced and thermal-induced reduction of bipyridinium occurs with a color change from light yellow to blue.

7.
Chem Commun (Camb) ; (1): 59-61, 2009 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-19081998

RESUMO

A unique supramolecular helix assisted by water tetramers is obtained by static evaporation of aqueous solution of a zwitterionic salt, 1,1'-bis(4-carboxylatebenzyl)-4,4'-bipyridinium; spontaneous chiral symmetry breaking occurs in crystallization; interestingly, redox chromism behavior of crystals upon exposure to alcohol atmosphere has been observed.


Assuntos
Compostos de Piridínio/química , Dicroísmo Circular , Cristalização , Ligações de Hidrogênio , Luz , Modelos Moleculares , Conformação Molecular , Oxirredução , Polímeros/química , Substâncias Redutoras , Estereoisomerismo , Viologênios/química , Água/química
8.
Dalton Trans ; (3): 355-62, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18411845

RESUMO

Three hybrid host-guest compounds {(MV)2[Ni(SCN)5].Cl.2H2O}n (1), {(MV)[Mn(N3)2(SCN)2]}n (2) and {(MV)[Co(N3)2(SCN)2}n (3) (where MV2+ = methylviologen dication) have been obtained by self-assembly methods and characterized by X-ray crystallography, spectral methods and magnetic measurements. Compound 1 shows a quasi-two-dimensional structure which is formed by novel single thiocyanate-bridged Ni(II) chains connected through S...S interactions. Compounds 2 and 3 are isostructural, containing single micro(1,3)-azide bridged Mn(II)/Co(II) square layers. MV2+, as a strong electron-acceptor and a template, is embedded between the anionic layers in all three compounds. The charge-transfer (CT) interactions between MV2+ and the anionic hosts have been revealed by structural analysis and UV-vis diffuse reflection spectroscopy. The magnetic studies of the compounds show antiferromagnetic interactions between adjacent metal ions (J = -34.52(7) cm(-1) for 1, J = -3.90(2) cm(-1) for 2 and J = -10.96(6) cm(-1) for 3).

9.
Bing Du Xue Bao ; 23(5): 394-8, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17969858

RESUMO

The total RNA was extracted from peripheral blood mononuclear cells (PBMC) which was isolated from Meishan porcine and induced with concanavaline A (ConA), then the porcine interferon gamma gene (PoIFNgamma, 501bp) was amplified by RT-PCR. The result of sequencing demonstrated that the amplified PoIFNgamma had 100% nucleotide homology with the other porcine IFNgamma sequence published on GenBank. The objective gene (PoIFNgamma) was inserted into adenoviral shuttle vector, pShuttle-CMV, to construct recombinant plasmid pSh-PoIFNgamma. And it was co-electrotransformated with adenoviral skeletal vector pAdEasy-1 into competent cells of BJ5183. The transforms were cultured at 37 degrees C for 24h on kanamycin resistance plate and selected for smaller colonies. Then, the extracted recombinant plasmid was named pAd-Sh-PoIFNgamma, which was confirmed by Pac I digestion, and transformed into XL10-Glod(r) for copious preparation. pAd-Sh-PoIFNgamma linearized with Pac I was co-transfected with liposome into 293 package cell-line. After 7d-10d, the typical cytopathic effect indicated that recombinant adenoviral genome (deleted with E1 and E3 genes) carrying PoIFNgamma was successfully packaged into intact virion. The recombinant virion was successively seeded to the 10th generation and the viral genome was extracted from each generation by PCR. The antiviral activity of PoIFNgamma was tested by CPE50 method. The results showed that the PoIFNgamma expressed by adenovirus had high antiviral activity, which was 1.3 x 10(6) U/mL against VSV in MDBK cells. The results demonstrated that the recombinant adenovirus carrying PoIFNgamma could be stably passaged.


Assuntos
Adenoviridae/genética , Antivirais/farmacologia , Interferon gama/genética , Animais , Interferon gama/farmacologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Suínos
10.
Wei Sheng Wu Xue Bao ; 47(1): 141-4, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17436641

RESUMO

Porcine interferon-gamma (PoIFN-gamma) of Chinese local brand, Meishan porcine, was cloned and inserted into retroviral vector pLXSN (neo r) . Using Lipofectamine, this recombinant plasmid was transfected into retroviral packing cell line, PA317 cells. These transfected cells were selected by DMEM containing 400microg/mL G418 for one week. RNA was extracted from the supernatant of these selected PA317 cells and the PoIFN-gamma gene could be amplified by RT-PCR. Pocine kidney cells and PK-15 cells were infected by the supernatant and were selected by 400 microg/mL, 600 microg/mL and 800 microg/mL G418, respectively. Those PK-15 cells were detected by indirect immunofluorescence assay and it was found that PoIFN-gamma mainly anchored in cellular membrane. The supernatant of the selected PK-15 was tested for the antiviral bioactivity after 48 hours of passage. The anti-VSV (vesicular stomatitis virus) activity in MDBK (bovine kidney cell) was 1200IU/10(6) cells. In addition, the effect of rPoIFNgamma-anti-FMDV was determined using cytopathic effect inhibition. The results indicate that PoIFN-gamma has been inserted into retroviral vector and recombinant retrovirus has been successfully packaged in PA317 cells. Furthermore, this retrovirus can infect PK-15 cells and express PoIFN-gamma with natural antiviral bioactivity and can inhibit VSV and FMDV.


Assuntos
Vetores Genéticos , Interferon gama/biossíntese , Interferon gama/genética , Rim/metabolismo , Retroviridae/genética , Animais , Técnica Indireta de Fluorescência para Anticorpo , Vírus da Febre Aftosa/efeitos dos fármacos , Interferon gama/farmacologia , Proteínas Recombinantes , Suínos , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos
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