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1.
Chemistry ; 29(58): e202300433, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37526193

RESUMO

A series of trimetallic cyanidometal-bridged compounds [Men Cp(dppe)FeII -(µ-NC)-RuII (MeOpy)4 -(µ-CN)-FeII (dppe)CpMen ] - [PF6 ]2 (N[PF6 ]2 , n=0, N =1; n=1, N=2; n=3, N=3; Cp=cyclopentadiene, dppe=1,2-bis(diphenylphosphino)ethane, MeOpy=4-methoxypyridine) and their one- and two-electron oxidized compounds N3+ and N4+ were synthesized and characterized. Meanwhile, a series of corresponding linear cyanido-bridged pentanuclear compounds [Men Cp(dppe)FeIII -(µ-NC)-RuII (MeOpy)4 -(µ-NC)-AgI -(µ-CN)-RuII (MeOpy)4 -(µ-CN)-FeIII (dppe)CpMen ][BF4 ]5 (M[BF4 ]5 , n=0, M=4; n=1, M=5; n=3, M=6) were also obtained and well characterized. The investigations suggest that in the trinuclear system there exists remote interaction between the two Fe centers, but no significant interactions exist across the central silver unit between the metals on the two sides of the silver center in the pentanuclear system. In both the trinuclear N4+ and the pentanuclear M5+ complexes, there exists the neighboring RuII →FeIII MM'CT transitions, and the MM'CT energy in the corresponding trinuclear system is higher than those in the pentanuclear system in which no remote metal-metal interaction occurs. Meanwhile, as the substituted methyl groups on the cyclopentadiene increases, the redox potential of the ruthenium in the trinuclear N4+ series increases, but that in the pentanuclear M5+ complexes decreases.

2.
Chemistry ; 28(34): e202104486, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35347776

RESUMO

To investigate the effects of cis/trans-configuration of the cyanidometal bridge and the electron donating ability of the auxiliary ligand on the cyanidometal bridge on metal to metal charge transfer (MMCT) in cyanidometal-bridged mixed valence compounds, two groups of trinuclear cyanidometal-bridged compounds cis/trans-[Cp(dppe)Fe(µ-NC)Ru(4,4'-dmbpy)2 (µ-CN)Fe(dppe)Cp][PF6 ]n (n=2 (cis/trans-1[PF6 ]2 ), 3 (cis/trans-1[PF6 ]3 ), 4 (cis/trans-1[PF6 ]4 )) and cis/trans-[Cp(dppe)Fe(µ-NC)Ru(bpy)2 (µ-CN)Fe(dppe)Cp][PF6 ]3 (cis/trans-2[PF6 ]3 ) were synthesized and fully characterized. The experimental results indicate that for these one- and two-electron oxidation mixed valence compounds, the trans-configuration compounds are more beneficial for MMCT than the cis-configuration compounds, and increasing the electron donating ability of the auxiliary ligand on the cyanidometal bridge is also conductive to MMCT. Moreover, compounds cis/trans-1[PF6 ]n (n=3, 4) and cis/trans-2[PF6 ]3 belong to localized compounds by analyzing the experimental characterization results, supported by the TDDFT calculations.

3.
Chemistry ; 27(43): 11183-11194, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-33939198

RESUMO

The synthesis and characterization of Class II-III mixed valence complexes have been an interesting topic due to their special intermediate behaviour between localized and delocalized mixed valence complexes. To investigate the influence of the isocyanidometal bridge on metal-to-metal charge transfer (MMCT) properties, a family of new isocyanidometal-bridged complexes and their one-electron oxidation products cis-[Cp(dppe)Fe-CN-Ru(L)2 -NC-Fe(dppe)Cp][PF6 ]n (n=2, 3) (Cp=1,3-cyclopentadiene, dppe=1,2-bis(diphenylphosphino)ethane, L=2,2'-bipyridine (bpy, 1[PF6 ]n ), 5,5'-dimethyl-2,2'-bipyridyl (5,5'-dmbpy, 2[PF6 ]n ) and 4,4'-dimethyl-2,2'-bipyridyl (4,4'-dmbpy, 3[PF6 ]n )) have been synthesized and fully characterized. The experimental results suggest that all the one-electron oxidation products may belong to Class II-III mixed valence complexes, supported by TDDFT calculations. With the change of the substituents of the bipyridyl ligand on the Ru centre from H, 5,5'-dimethyl to 4,4'-dimethyl, the energy of MMCT for the one-electron oxidation complexes changes in the order: 13+ <23+ <33+ , and that for the two-electron oxidation complexes decreases in the order 14+ >34+ >24+ . The potential splitting (ΔE1/2 (2)) between the two terminal Fe centres for N[PF6 ]2 are the largest potential splitting for the cyanido-bridged complexes reported so far. This work shows that the smaller potential difference between the bridging and the terminal metal centres would result in the more delocalized mixed valence complex.

4.
Angew Chem Int Ed Engl ; 57(43): 14046-14050, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30182522

RESUMO

The two stable pairs of trimetallic compounds trans-[Cp*(dppe)Ru(µ-NC)Ru(dmap)4 (µ-CN)Ru(dppe)Cp*][PF6 ]n (1[PF6 ]n , n=2, 3; Cp*=1,2,3,4,5-pentamethylcyclopentadiene; dppe=1,2-bis-(diphenylphosphino)ethane; dmap= 4-dimethylaminopyridine) and trans-[Cp*(dppe)Ru(µ-CN)Ru(dmap)4 (µ-NC)Ru(dppe)Cp*][PF6 ]n (2[PF6 ]n , n=2, 3), which demonstrate cyanide/isocyanide isomerism, have been synthesized and fully characterized. 13+ [PF6 ]3 and 23+ [PF6 ]3 are the one-electron oxidation products of 12+ [PF6 ]2 and 22+ [PF6 ]2 , respectively. The results suggest that 1[PF6 ]3 is a class III mixed valence compound, whereas 2[PF6 ]3 might be an unusually symmetrical class II-III mixed valence compound composed of the two asymmetrical delocalized RuIII -NC-RuII mixed valence subunits.

5.
Inorg Chem ; 56(11): 6275-6280, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28537718

RESUMO

Enantioseparation is an integral process in the pharmaceutical industry, considering the ever-increasing demand for chiral medicine products. As a new material, porous metal-organic frameworks (MOFs) have shown their potential application in this field because their structures are easy to adjust and control. Though chiral recognition between racemic substrates and frameworks has made preliminary progress, discussions of their size-matching effects are rare. Herein with the help of channel-tunable homochiral MOFs (HMOFs), diols of different sizes have been separated in good enantiomeric excess (ee%). In addition, the ee% reaches 67.4% for the first time for diols as large as 1,1,2-triphenyl-1,2-ethanediol, which turns out to be the most effective value so far.


Assuntos
Álcoois/química , Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Estereoisomerismo , Propriedades de Superfície
6.
Angew Chem Int Ed Engl ; 56(6): 1605-1609, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28079947

RESUMO

The heterometallic complexes trans-[Cp(dppe)FeNCRu(o-bpy)CNFe(dppe)Cp][PF6 ]n (1[PF6 ]n , n=2, 3, 4; o-bpy=1,2-bis(2,2'-bipyridyl-6-yl)ethane, dppe=1,2-bis(diphenylphosphino)ethane, Cp=1,3-cyclopentadiene) in three distinct states have been synthesized and fully characterized. 13+ [PF6 ]3 and 14+ [PF6 ]4 are the one- and two-electron oxidation products of 12+ [PF6 ]2 , respectively. The investigated results suggest that 1[PF6 ]3 is a Class II mixed valence compound. 1[PF6 ]4 after a thermal treatment at 400 K shows an unusually delocalized mixed valence state of [FeIII -NC-RuIII -CN-FeII ], which is induced by electron transfer from the central RuII to the terminal FeIII in 1[PF6 ]4 , which was confirmed by IR spectroscopy, magnetic data, and EPR and Mössbauer spectroscopy.

7.
Chemistry ; 22(15): 5327-34, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26919304

RESUMO

The pores/channels of porous 3D metal-organic frameworks (MOFs) have been widely applied to incorporate gas, solvent, or organic molecules. On the contrary, the utilization of the interlamellar void of layered metal-organic complexes (MOCs) remains underappreciated, although it is more flexible and available to accommodate molecules with different sizes. In this work, diverse sulfonates have been intercalated purposely into an identical layered MOC, which constructed various novel intercalation compounds possessing fluorescent, white-light emitting, photochromic, homochiral, or nonlinear optical (NLO) properties. With the help of single-crystal X-ray diffraction, their structures and the mutual interactions between the MOC host and the sulfonate guests were characterized. The properties of the guest molecules were tuned and meanwhile some new performances were generated after confining them into the interlayer region. Such a hybrid approach provides an efficient strategy to design and prepare multifunctional materials.

8.
Chemistry ; 22(13): 4460-8, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26864609

RESUMO

A new mixed-ligand metal-organic framework (MOF), ZnATZ-BTB, has been constructed as a luminescent ratiometric thermometer by making use of the intrinsic dual emission at cryogenic temperatures. Its twofold interpenetrated network promotes the Dexter energy transfer (DET) between the mixed organic lumophores. The temperature-dependent luminescent behavior arises from the thermal equilibrium between two separated excited states coupled by DET, which is confirmed by Boltzmann distribution fitting. The small excited-state energy gap allows ZnATZ-BTB to measure and visualize cryogenic temperatures (30-130 K) with significantly high relative sensitivity (up to 5.29% K(-1) at 30 K). Moreover, it is the first example of a ratiometric MOF thermometer the dual emitting sources of which are widely applicable mixed organic ligands, opening up new opportunities for designing such devices.

9.
Inorg Chem ; 55(9): 4199-205, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-27093469

RESUMO

A mixture of 2D and 1D metal-organic complexes, [ZnL(H2O)2·G1·DEF·2H2O]n (1a: G1 = naphthalene-2,7-disulfonate; DEF = N,N-diethylformamide) and [ZnL(H2O)3·G1·DEF·2H2O]n (2), has been prepared from a hydrogenated Schiff base L and Zn(II) in a DEF-contained solvent system under mild conditions. The yields of 1a and 2 are equivalent; however, they can be tuned by varying the amount of DEF solvent. Increasing the use of DEF tends to form pure 1a, while decreasing it generates 2. Without DEF, another novel 3D four-connected CdSO4 (cds) framework [ZnL(H2O)2·G1·2H2O]n (3) composed of alternated right-handed and left-handed helical chains has been constructed. The amount of DEF solvent has a significant impact on the diverse coordination architectures of 1-3, which is rare in the preparation of metal-organic complexes. The photoluminescence of complexes 1-3 along with naphthalene-2,7-disulfonate has been investigated in the solid state. The luminescent emission of G1 was enhanced greatly after being confined into metal-organic networks. In addition, complexes 1-3 display second-harmonic generation efficiencies, which are approximately 0.58, 0.42, 0.32, and 0.52 times as much as that of potassium dihydrogen phosphate.

10.
Inorg Chem ; 54(8): 3951-7, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25853322

RESUMO

Utilizing the mixed-ligand strategy, a novel fourfold-interpenetrated 3D homochiral metal-organic framework (1) with rare pair quadruple-stranded helices was assembled from bpee (1,2-bis(4-pyridyl)ethylene) and NCG (N-carbamyl-l-glutamate). Changing the carbamyl substituent of NCG with benzoyl group (NBzG: N-benzoyl-l-glutamate), a non-interpenetrated 3D homochiral coordination polymer (2) composed of alternate right-handed and left-handed single helix was obtained. When p-tolylsulfonyl substituent was used instead, an interesting homochiral linear structure (3) was formed from mixed-ligand bpee and NTsG (N-p-tolylsulfonyl-l-glutamate), with all individual NTsG being lined up orderly. The steric hindrance of N-substituent of l-glu has a tremendous impact on the construction of these diverse frameworks. Complexes 1-3 display second harmonic generation (SHG) efficiencies, which are approximately 0.32, 0.45, and 0.55 times as much as that of KDP powder.


Assuntos
Complexos de Coordenação/química , Etano/análogos & derivados , Glutamatos/química , Piridinas/química , Zinco/química , Complexos de Coordenação/síntese química , Etano/química , Ligantes , Modelos Moleculares , Estrutura Molecular
11.
Chemistry ; 20(5): 1341-8, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24458914

RESUMO

The microporous metal-organic framework (MMOF) Zn4O(L1)2⋅9 DMF⋅9 H2O (1-H) and its functionalized derivatives Zn4O(L1-CH3)2⋅9 DMF⋅9 H2O (2-CH3) and Zn4O(L1-Cl)2⋅9 DMF⋅9 H2O (3-Cl) have been synthesized and characterized (H3L1=4-[N,N-bis(4-methylbenzoic acid)amino]benzoic acid, H3L1-CH3=4-[N,N-bis(4-methylbenzoic acid)amino]-2-methylbenzoic acid, H3L1-Cl=4-[N,N-bis(4-methylbenzoic acid)amino]-2-chlorobenzoic acid). Single-crystal X-ray diffraction analyses confirmed that the two functionalized MMOFs are isostructural to their parent MMOF, and are twofold interpenetrated three-dimensional (3D) microporous frameworks. All of the samples possess enduring porosity with Langmuir surface areas over 1950 cm(2) g(-1). Their pore volumes and surface areas decrease in the order 1-H>2-CH3 >3-Cl. Gas-adsorption studies show that the H2 uptakes of these samples are among the highest of the MMOFs (2.37 wt% for 3-Cl at 77 K and 1 bar), although their structures are interpenetrating. Furthermore, this work reveals that the adsorbate-adsorbent interaction plays a more important role in the gas-adsorption properties of these samples at low pressure, whereas the effects of the pore volumes and surface areas dominate the gas-adsorption properties at high pressure.

12.
Chemistry ; 20(23): 7025-36, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24771667

RESUMO

To investigate how the central metalloligand geometry influences distant or vicinal metal-to-metal charge-transfer (MMCT) properties of polynuclear complexes, cis- and trans-isomeric heterotrimetallic complexes, and their one- and two-electron oxidation products, cis/trans-[Cp(dppe)Fe(II)NCRu(II)(phen)2CN-Fe(II)(dppe)Cp][PF6]2 (cis/trans-1[PF6]2), cis/trans-[Cp(dppe)Fe(II)NCRu(II)(phen)2CNFe(III)-(dppe)Cp][PF6]3 (cis/trans-1[PF6]3) and cis/trans-[Cp(dppe)Fe(III)NCRu(II)(phen)2CN-Fe(III)(dppe)Cp][PF6]4 (cis/trans-1[PF6]4) have been synthesized and characterized. Electrochemical measurements show the presence of electronic interactions between the two external Fe(II) atoms of the cis- and trans-isomeric complexes cis/trans-1[PF6]2. The electronic properties of all these complexes were studied and compared by spectroscopic techniques and TDDFT//DFT calculations. As expected, both mixed valence complexes cis/trans-1[PF6]3 exhibited different strong absorption signals in the NIR region, which should mainly be attributed to a transition from an MO that is delocalized over the Ru(II)-CN-Fe(II) subunit to a Fe(III) d orbital with some contributions from the co-ligands. Moreover, the NIR transition energy in trans-1[PF6]3 is lower than that in cis-1[PF6]3, which is related to the symmetry of their molecular orbitals on the basis of the molecular orbital analysis. Also, the electronic spectra of the two-electron oxidized complexes show that trans-1[PF6]4 possesses lower vicinal Ru(II) → Fe(III) MMCT transition energy than cis-1[PF6]4. Moreover, the assignment of MMCT transition of the oxidized products and the differences of the electronic properties between the cis and trans complexes can be well rationalized using TDDFT//DFT calculations.


Assuntos
Complexos de Coordenação/síntese química , Cianetos/química , Compostos Ferrosos/química , Rutênio/química , Complexos de Coordenação/química , Cristalografia por Raios X , Técnicas Eletroquímicas , Espectroscopia de Ressonância de Spin Eletrônica , Isomerismo , Conformação Molecular , Teoria Quântica , Espectrofotometria Infravermelho
13.
Inorg Chem ; 52(21): 12305-7, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24131207

RESUMO

Complex 1 exhibits the crownlike structure with the unprecedented 12-membered ring system, while in 2, a cagelike cluster has been connected with two distorted cores in nickel thiolates. The synthesis of novel clusters by way of C-S bond cleavage was first reported in the field of nickel thiolates.

14.
Inorg Chem ; 52(19): 11343-50, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24041218

RESUMO

Cis- and trans-isomeric heterotrinuclear-metallic complexes and their two-electron-oxidation products, cis-/trans-[Cp(dppe)Fe(µ-CN)Ru(bpy)2(µ-CN)Fe(dppe)Cp][PF6]2 (cis-/trans-1[PF6]2) and cis-/trans-[Cp(dppe)Fe(µ-CN)Ru(bpy)2(µ-CN)Fe(dppe)Cp][PF6]4 (cis-/trans-1[PF6]4), have been synthesized and structurally characterized. To the best of our knowledge, the complexes are the first example of a cis-/trans-isomer with multistates. Although separated by the diamagnetic cyanido-metal bridge, the two distant paramagnetic metal centers in both the oxidized complexes exhibit quite strong magnetic couplings. As a unique example, cis-1[PF6]4 is antiferromagnetic, and trans-1[PF6]4 is ferromagnetic. Density functional theory (DFT) calculations suggest that the spin-delocalization mechanism should be responsible for the magnetic interactions between the two distant paramagnetic Fe(III) centers across the diamagnetic cyanido-metal in both cis- and trans-1(4+). Most importantly, the DFT calculations revealed that the type (antiferromagnetic or ferromagnetic) and strength (J) of the magnetic interactions in such compounds can be controlled by the variation (cis or trans) of the diamagnetic central metal configurations.

15.
Dalton Trans ; 52(45): 16858-16869, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37910432

RESUMO

In order to investigate the properties of metal to metal charge transfer (MMCT) influenced by the relative energy level between the bridging unit and the terminal unit, two groups of heterotrimetallic cyanido-metal-bridged complexes, trans-[Cp(dppe)Fe-CN-Ru(MeOpy)4-NC-Fe(dppe)Cp][X]n (1[X]n; n = 2, 3, or 4; X = PF6 or BF4) (Cp = cyclopentadiene, dppe = 1,2-bis(diphenylphosphino)ethane, MeOpy = 4-methoxypyridine) and [Cp*(dppe)Fe-CN-Ru(MeOpy)4-NC-Fe(dppe)Cp*] [X]n (2[X]n; Cp* = 1,2,3,4,5-pentamethylcyclopentadiene; n = 2, 3, or 4; X = PF6 or BF4) were synthesized and fully characterized. The crystallography data suggest different oxidation sites in the ground state for one-electron oxidation products 13+ and 23+, and the electrochemical and Mössbauer spectra suggest that in the one-electron oxidation compounds 13+, the charge is delocalized all along the trimetal backbone Fe-Ru-Fe, while in 23+, the charge is rather delocalized between the two metal parts Fe-Ru. Further oxidation of N3+ gives N4+ (N = 1 or 2), during which a spin transfer towards the terminal units is observed in both series.

16.
Dalton Trans ; 51(36): 13938-13948, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36040443

RESUMO

To investigate the electron transfer properties between metal centers and their influencing factors in binuclear and trinuclear cyanido-bridged mixed valence complexes with cis/trans-configuration, binuclear cis-[Cp(dppe)Fe(µ-NC)Ru(5,5'-dmbpy)2(µ-CN)][PF6]n (cis-1[PF6]n, n = 1, 2) and trinuclear cis/trans-[Cp(dppe)Fe(µ-NC)Ru(5,5'-dmbpy)2(µ-CN)Fe(dppe)Cp][PF6]n (cis/trans-2[PF6]n, n = 2, 3, 4) (Cp = 1,3-cyclopentadiene, dppe = 1,2-bis(diphenylphosphino)ethane, 5,5'-dmbpy = 5,5'-dimethyl-2,2'-bipyridyl) cyanido-bridged complexes were synthesized and well characterized. The experimental results indicate that the presence of the other terminal fragment Cp(dppe)FeIII in cis-2[PF6]4 results in higher MMCT energy than that of cis-1[PF6]2. In addition, the trans-configuration is more conducive to electron transfer between metal centers than the cis-configuration in trinuclear cyanido-bridged mixed valence complexes. Moreover, these mixed valence complexes cis-1[PF6]2 and cis/trans-2[PF6]n (n = 3, 4) could be assigned to Class II systems according to Robin and Day.

17.
Bioengineered ; 13(5): 13312-13327, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35635086

RESUMO

Studies demonstrate that long non-coding RNAs (lncRNAs) play vital roles in cancer progression. However, the expression pattern and molecular mechanisms of lncRNA FAM83A-AS1 in lung cancer remain largely unclear. Here, we analyzed FAM83A-AS1 expression in lung cancer tissues from three RNA-sequencing (RNA-Seq) datasets and validated these results using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) in an independent set of lung adenocarcinoma. Cell proliferation, migration, invasion, and autophagy were analyzed after knockdown FAM83A-AS1 with siRNAs. The underlying molecular mechanisms of FAM83A-AS1 were performed by Western blot, qRT-PCR, and RNA-seq analysis. We found that FAM83A-AS1 was up-regulated in lung cancer and elevated expression was associated with poor patient survival. These results were confirmed using RT-PCR in an independent set of lung cancer. Functional study indicated that FAM83A-AS1 knockdown reduced cell proliferation, migration, invasion, and colony formation in cancer cells. FAM83A-AS1 silencing induced autophagy and cell cycle arrest at G2. Mechanistically, serval oncogenic proteins such as EGFR, MET, PI3K, and K-RAS were decreased upon FAM83A-AS1 silencing, while phosphor AMPKα and ULK1 were increased. Based on the above results, we believe that FAM83A-AS1 may have potential as a diagnosis/prognosis marker and its oncogenic role and autophagy regulation may be through MET-AMPKα signaling, which could lead to potential targeting for lung cancer therapy.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , RNA Longo não Codificante , Proteínas Quinases Ativadas por AMP , Adenocarcinoma/patologia , Autofagia/genética , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-met , RNA Antissenso/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
18.
Inorg Chem ; 50(16): 7618-24, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21744812

RESUMO

Three novel coordination polymers, [Cd(5)(HTTHA)(2)(Hpt)(4)(H(2)O)]·4H(2)O (1; H(6)TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid, Hpt = pyridinium-4-thiolate), {[Cd(3)(TTHA)(dps)(H(2)O)(3)](2)}·H(2)O (2), and [Zn(3)(TTHA)(dps)(H(2)O)]·5H(2)O (3; dps =4,4'-dipyridylsulfide), have been synthesized by the flexible hexapodal acid H(6)TTHA and in-situ-generated Hpt and dps ligands from a 4,4'-dipyridyldisulfide (dpds) precursor through cleavage of both S-S and S-C(sp(2)) bonds and temperature-dependent chemical rearrangement under hydrothermal conditions. Polymers 2 and 3 exhibit 3D frameworks, while in 1, the extended 3D network can be described as 2D layers further bridged via H-bond interaction. Intriguingly, the three compounds have shown an unusual luminescence thermochromism. Upon decreasing the temperature from 298 to 10 K, the emission bands grow in intensity and change in color dramatically.

19.
Dalton Trans ; 50(18): 6161-6169, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33861281

RESUMO

In order to investigate the influence of the auxiliary ligand of the cyanidometal bridge on metal to metal charge transfer (MMCT) in cyanidometal-bridged complexes, two groups of heterotrimetallic cyanidometal-bridged complexes, trans-[Cp*(dppe)Fe-NC-Ru(L)2-CN-Fe(dppe)Cp*][PF6]n (L = bpy, 1(PF6)n; L = 4,4'-dmbpy, 2(PF6)n; n = 2, 3, 4) (Cp* = 1,2,3,4,5-pentamethylcyclopentadiene, dppe = 1,2-bis(diphenylphosphino)ethane, bpy = 2,2'-bipyridine, 4,4'-dmbpy = 4,4'-dimethyl-2,2'-bipyridyl) were synthesized and fully characterized. The MMCT of the one-electron oxidation mixed valence complexes is mainly attributed to RuII and FeII → FeIII MMCT transitions, and the MMCT of the two-electron oxidation complexes is mainly attributed to RuII → FeIII MMCT transitions. The energy of the MMCT of the four complexes decreases with the increase of the electron donating ability of the auxiliary ligand of the cyanidometal bridge. The IR, EPR, and Mössbauer spectra, and the solvent independence of MMCT characterizations indicate that the one-electron oxidation mixed valence complexes may belong to Class II-III systems, and the two-electron oxidation complexes may be localized at low temperature but delocalized at room temperature on the EPR timescale.

20.
Mol Ther Nucleic Acids ; 22: 1164-1175, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33312753

RESUMO

Long noncoding RNA (lncRNA) LINC00857 has been reported to be upregulated in lung cancer and related to poor patient survival. It can regulate cell proliferation and tumor growth in lung cancer as well as several other cancers. However, the underlying molecular mechanisms that are regulated by LINC00857 are unclear. In this study, we found that LINC00857 silencing can impair cell proliferation in 14 different genomic alterations of lung cancer cell lines. These alterations are EGFR, KRAS, TP53, MET, and LKB1 mutations. The cell apoptosis and autophagy were induced upon LINC00857 silencing in lung cancer cells. Mechanistically, LINC00857 can bind to the Y-box binding protein 1 (YBX1) protein, prevent it from proteasomal degradation, and increase its nuclear translocation. LINC00857 regulated MET expression via YBX1 at a transcriptional level. Induced cell autophagy by LINC00857 knockdown was mainly through increased phosphor-AMP-activated protein kinase (p-AMPK)a. Collectively, LINC00857-YBX1-MET/p-AMPKa signaling is critical to regulate cell proliferation, apoptosis, and autophagy, which may provide a potential clinically therapeutic target in lung cancer.

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