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1.
Small ; : e2402523, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747010

RESUMO

A 44.610.8 topology hybrid ultramicroporous material (HUM), {[Cu1.5F(SiF6)(L)2.5]·G}n, (L = 4,4'-bisimidazolylbiphenyl, G = guest molecules), 1, formed by cross-linking interpenetrated 3D four-connected CdSO4-type nets with hexafluorosilicate anions is synthesized and evaluated in the context of gas sorption and separation herein. 1 is the first HUM functionalized with two different types of fluorinated sites (SiF6 2- and F- anions) lining along the pore surface. The optimal pore size (≈5 Å) combining mixed and high-density electronegative fluorinated sites enable 1 to preferentially adsorb C2H2 over CO2 and C2H4 by hydrogen bonding interactions with a high C2H2 isosteric heat of adsorption (Qst) of ≈42.3 kJ mol-1 at zero loading. The pronounced discriminatory sorption behaviors lead to excellent separation performance for C2H2/CO2 and C2H2/C2H4 that surpasses many well-known sorbents. Dynamic breakthrough experiments are conducted to confirm the practical separation capability of 1, which reveal an impressive separation factor of 6.1 for equimolar C2H2/CO2 mixture. Furthermore, molecular simulation and density functional theory (DFT) calculations validate the strong binding of C2H2 stems from the chelating fix of C2H2 between SiF6 2- anion and coordinated F- anion.

2.
ACS Appl Mater Interfaces ; 15(31): 37602-37608, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37504065

RESUMO

Chloroform is a volatile organic solvent and a contaminant that is slightly soluble in water, making the reversible separation of chloroform from water a critical and challenging task within the chemical and environmental industries. In this study, we present a newly developed coordination framework, [Zn(4-pmntd)(opa)] [4-pmntd, N,N'-bis(4-pyridylmethyl)naphthalene diimide; opa, o-phthalic acid], which demonstrates a high adsorption capacity for chloroform (2.5 mmol/g) and an excellent ability to separate chloroform from water. The effectiveness of chloroform extraction by Zn(4-pmntd)(opa) was confirmed through vapor sorption, grand canonical Monte Carlo simulation, and 1H nuclear magnetic resonance spectroscopy. The porous framework was also utilized to create a filtration film using natural rubber, which successfully separated chloroform from water with a minimum test concentration of approximately 1 × 10-6 mol/L and a chloroform purity of 99.2%. [Zn(4-pmntd)(opa)] therefore has significant potential for low-energy separation and recycling of chloroform from water under ambient conditions.

3.
Front Immunol ; 14: 1269069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162659

RESUMO

Background: Observational studies have identified a heightened risk of osteoporosis and fractures in patients with primary biliary cholangitis (PBC). However, conclusive evidence establishing a causal relationship between the two, and a clear mechanism explaining this association, remains elusive. Methods: We conducted a bidirectional two-sample Mendelian randomization (MR) analysis to investigate the causal relationship between PBC and osteoporosis. This analysis utilized five MR methods: inverse-variance weighted (IVW), MR-Egger, weighted median, weighted mode, and simple mode. Sensitivity analyses were performed, employing various models and testing methods, to assess the impact of heterogeneity and pleiotropy on the results and to confirm their robustness. Results: A causal relationship between PBC and osteoporosis risk was established through IVW analysis (OR: 1.049, 95%CI: 1.017-1.082, P=0.002). Three other MR analyses corroborated these findings. Conversely, osteoporosis was not found to causally affect PBC risk, as evidenced by IVW analysis (OR: 0.941, 95%CI: 0.783-1.129, P=0.511). Across all MR analyses, no heterogeneity or horizontal pleiotropy was detected among the instrumental variables (IVs). Furthermore, the leave-one-out analysis indicated that no single SNP disproportionately influenced the results, affirming the reliability of the bidirectional MR findings. Conclusion: This study establishes a positive causal relationship between PBC and the risk of osteoporosis, while no definitive causal link was found from osteoporosis to PBC. These findings offer new insights and guidance for managing bone health in PBC patients.


Assuntos
Fraturas Ósseas , Cirrose Hepática Biliar , Osteoporose , Humanos , Cirrose Hepática Biliar/epidemiologia , Cirrose Hepática Biliar/genética , Análise da Randomização Mendeliana , Reprodutibilidade dos Testes , Osteoporose/epidemiologia , Osteoporose/genética
4.
Chem Commun (Camb) ; 58(8): 1159-1162, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34981095

RESUMO

A bulky 1,4-di-iodobenzene having four adjacent para-tBu-C6H4 group (Ar') substituents (1) was used to prepare the di-hypervalent iodine compound 1,4-[I(OAc)2]2-2,3,5,6-Ar'4-C6 (2). Despite the steric encumbrance of the iodine center by the flanking aryl substituents, compound 2 undergoes ready cyclization under mild conditions (excess CF3COOH at 55 °C, 30 min) to afford a dicyclic di-iodonium di-triflate salt 3. The single crystal structures of compounds 2 and 3 were examined and compared to the formerly characterized precursor 1. The para-tert-butyl groups on these compounds also render the compounds more soluble than multifunctional hypervalent iodine (HVI) compounds. HVI compounds having multiple iodine(III) centers are increasingly of interest for applications as recyclable reagents, materials precursors, and as Lewis acids.

5.
Gen Physiol Biophys ; 40(3): 173-182, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34100374

RESUMO

This study aimed to identify more biomarkers associated with osteosarcoma progression via lncRNA-mRNA co-expression network. Dataset GSE99671 was downloaded from GEO database. The mRNAs and lncRNAs that were differentially expressed between tumor and normal samples were screened out. Functional enrichment analysis of differentially expressed mRNAs was carried out, followed by weighted gene correlation network analysis (WGCNA). Based on the lncRNAs and mRNAs, a lncRNA-mRNA co-expression network was constructed. Total 703 mRNAs and 7 lncRNAs were differentially expressed between tumor and normal tissues. The mRNAs were significantly enriched in functions associated with inflammatory response as well as autoimmune thyroid disease and ribosome pathways. WGCNA revealed that ME2 module had a high correlation with tumor, and ST3GAL4, UCK2, PSAT1 etc. had higher connectivity degrees in this module. lncRNA-mRNA co-expression network showed that 12 mRNAs, such as PEMT, COL10A1 and GSTA1, were synergistically expressed with lncRNA TTTY14. Inflammatory response and ribosome synthesis may play important role in osteosarcoma progression. lncRNA TTTY14 may affect the development of osteosarcoma by cooperative expression with PEMT, COL10A1, GSTA1, etc. ST3GAL4, UCK2, PSAT1 as well as TTTY14 may serve as key biomarkers in osteosarcoma.


Assuntos
Neoplasias Ósseas , Osteossarcoma , RNA Longo não Codificante , Perfilação da Expressão Gênica , Humanos , Osteossarcoma/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética
6.
Inorg Chem ; 60(11): 7865-7875, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33970618

RESUMO

Hypervalent iodine (HVI) compounds are very important selective oxidants often employed in organic syntheses. Most HVI compounds are strongly associated in the solid state involving interactions between the electropositive iodine centers and nearby electron lone pairs of electronegative atoms. This study examines the impact of remote substituents on select families of HVI compounds as means to achieve predictable two-dimensional extended solid-state materials. Crystallographic analyses of 10 HVI compounds from several related classes of λ3 organoiodine(III) compounds, (diacetoxyiodo)benzenes, (dibenzoatoiodo)benzenes, [bis(trifluoroacetoxy)iodo]benzenes, and µ-oxo-[(carboxylateiodo)benzenes], provide insights into how remote substituents and the choice of carboxylate groups can impact intermolecular interactions in the solid state.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 254: 119588, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33743311

RESUMO

Five diverse 1D supramolecular chains, {[4-pmntd]}n(1), {H2[4-pmntd]•2Br-}n(2), {H2[4-pmntd]•2NO3-}n(3), {H2[4-pmntd]•2ClO4-}n(4), {H2[4-pmntd]•2BF4-}n(5), (where 4-pmntd was N,N'-bis (4-pyridylmethyl)naphthalene diimide) were synthesized and characterized by X-ray single-crystal structure analysis, IR spectroscopy, elemental analyses, thermogravimetric analyses, fluorescence detection. The anions effect construction of their 1D chain structural diversity through different π interactions. Compound 1 through the adjacent pyridine rings parallel π∙∙∙π interactions formed 1D linear chain structure. Compound 2 through Br- anion∙∙∙π interactions and halogenbond interactions formed 1D zigzag chain structure. Compound 3 through lone pair∙∙∙π interactions of naphthalene diimide and the adjacent carboxyl group formed 1D stairway chain structure. Compound 4 through ClO4- anion∙∙∙π interactions formed 1D ribbon chain structure. Compound 5 through parallel π∙∙∙π interactions of the adjacent naphthalene diimide planes and pyridine rings formed 1D ladder chain structure. The five compounds' fluorescence properties and thermal stabilities were investigated. The compound 2 solution could fluorescence detection for iodide anion via fluorescence quenching.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117941, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31884400

RESUMO

Three diverse supramolecular compounds, {[3-pmpmd]}n(1), {H2[3-pmpmd]·2NO3-}n(2), {H2[3-pmpmd]·2tbb}n(3), (where 3-pmpmd was N,N'-bis(3-pyridylmethyl)pyromellitic diimide; tbb was tertiary butyl benzoic acid) were synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X-ray single-crystal structure analysis. The co-crystal anions affect their structural diversity. Compound 1 is a 1D stairway chain structure by perpendicular π⋯π interactions of pyromellitic diimide and the neighboring pyridine rings. Compound 2 is a typical 1D ladder chain structure by hydrogen bond of nitrate arranged in a parallel array. Compound 3 is a 1D zigzag chain structure of one 3-pmpmd and two tbb by parallel π⋯π interactions and hydrogen bond interactions. Thermal stabilities and fluorescence properties of all compounds were investigated. The solution of compound 2 in DMF can fluorescence sense for iodide ions by remarkably quenching fluorescence intensity.

9.
ACS Omega ; 4(1): 1995-2000, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459450

RESUMO

The selective separation of ethanol/acetonitrile by porous materials has rarely been observed owing to their similar physicochemical properties. In this work, we report a new coordination network, [Cu2(4-pmntd)2(opd)2](4-pmntd = N,N'-bis(4-pyridymethy)naphthalene diimide, opd = disodium 1,2-benzenedicarboxylate), which exhibits selective separation of ethanol over acetonitrile. The weak coordination bonds formed by unsaturated Cu2+ sites and hydroxyl groups are the key to such performance.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 187: 168-173, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-28686918

RESUMO

Two complexes, {[Mn(3-pmpmd)2(Cl)2]·2H2O}n(1), {[Cd(3-pmpmd) (I)2]·CHCl3·H2O}n(2), (3-pmpmd, N,N'-bis(3-pyridylmethyl)pyromellitic diimide) were synthesized and characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X-ray single-crystal structure analysis. The conformations of 3-pmpmd ligand affect their structural diversity. Complex 1 is a 1D double chain structure in edge-to-edge arrangement by π⋯π interactions. Complex 2 is a typical 1D zigzag chain structure arranged in a parallel array containing 1D channel to accommodate the chloroform and water guest molecules. Thermal stabilities and fluorescence properties of both complexes were investigated. The solution of complex 2 in DMF can sense for I- anion by quenching fluorescence intensity, whereas other anions increasing fluorescence intensity.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 878-82, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25155944

RESUMO

A new complex [Zn(bbb)Cl2]·DMF, where bbb is 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole, was synthesized and characterized by element analysis, (1)H NMR and X-ray single crystal structure analyses. For complex: crystal system, triclinic, space group, P-1, a=9.4661(13), b=10.3534(14), c=13.0025(18)Å, α=73.477(2), ß=80.743(2), γ=88.658(2)°, V=1205.5(3)Å(3), Z=2. In this complex, the Zn(2+) distorted tetrahedron geometry is coordinated by two nitrogen atoms from 2-(2-(1H-benzo[d]imidazol-2-yl)benzyl)-1H-benzo[d]imidazole and two Cl(-). The complex emits yellow green luminescence with the maximal emission peak at 550 nm in DMF solution. The complex exhibits inhibition on the growth of Eca109 cancer cell with IC50 value of 8.9±1.1 µM, which was lower than that of cisplatin (14.3±1.4 µM). This complex has potential application in treatment of esophageal cancer.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Imidazóis/síntese química , Imidazóis/farmacologia , Luminescência , Zinco/farmacologia , Antineoplásicos/química , Benzimidazóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Imidazóis/química , Ligantes , Conformação Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termogravimetria
12.
IUCrJ ; 1(Pt 5): 318-27, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25295173

RESUMO

A rare example is reported in which discrete Ag2 L 2 ring and (AgL)∞ chain motifs [L = N,N'-bis(3-imidazol-1-yl-propyl)-pyromellitic diimide] co-crystallize in the same crystal lattice with varying ratios and degrees of disorder. Crystal structures obtained from representative crystals reveal compatible packing arrangements of the cyclic and polymeric isomers within the crystal lattice, which enables them to co-exist within a crystalline solid solution. A feasible pathway for transformation between the isomers is suggested via facile rotation of the coordinating imidazolyl groups. This chemical system could provide a chance for direct observation of ring-opening isomerization at the crystal surface. Mass spectrometry and (1)H NMR titration show a dynamic equilibrium between cyclic and oligomeric species in solution, and a potential crystallization process is suggested involving alignment of precursors directed by aromatic stacking interactions between pyromellitic diimide units, followed by ring-opening isomerization at the interface between the solid and the solution. Both cyclic and oligomeric species can act as precursors, with interconversion between them being facile due to a low energy barrier for rotation of the imidazole rings. Thermogravimetric analysis and variable-temperature powder X-ray diffraction indicate a transition to a different crystalline phase around 120°C, which is associated with loss of solvent from the crystal lattice.

13.
Dalton Trans ; 41(15): 4626-33, 2012 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-22377990

RESUMO

Four semirigid ditopic ligands, N,N'-bis(3-pyridylmethyl)-pyromellitic diimide (L(1)), N,N'-bis(4-pyridylmethyl)-pyromellitic diimide (L(2)), N,N'-bis(3-pyridylmethyl)-naphthalene diimide (L(3)), and N,N'-bis(4-pyridylmethyl)-naphthalene diimide (L(4)), reacted with Cd(NO(3))(2) to result in four cadmium(II) complexes, namely, {[Cd(2)(L(1))(2)(NO(3))(4)(CH(3)OH)(4)]·H(2)O} (1), [Cd(L(2))(NO(3))(2)(CH(3)OH)(2)·Cd(2)(L(2))(3)(NO(3))(4)]·{4(HCCl(3))·2H(2)O}(n) (2), {[Cd(L(3))(2)(NO(3))(2)]}(n) (3), and {[Cd(L(4))(2)(NO(3))(2)]·2(CHCl(3))}(n) (4). These complexes have been characterized by elemental analyses, powder X-ray diffraction, thermogravimetric (TG) analyses, IR spectroscopy, and single-crystal X-ray diffraction. Structural analyses show that four types of structures are formed: (1) a discrete M(2)L(2) ring with two Cd ions and two cis-L(1) ligands comprising a zero-dimensional molecular rectangle (0D), (2) an unusual zigzag linear chain and a one-dimensional ladder existing simultaneously in the crystal lattice (1D), (3) a two-dimensional network of the (4,4) net structure (2D), and (4) an unusual chiral three-dimensional framework with 5-fold interpenetrating diamond (dia) topology (3D). In these complexes, the ligands exhibit different coordination modes and construct various architectures by bridging Cd(NO(3))(2) inorganic building blocks. These results suggest that structural diversity of the complexes is tunable by ligand modifications, that is, varying the ligand spacer bulkiness or substituent position of terminal group. Furthermore, gas adsorption measurements indicate that 4 possesses moderate CO(2) uptake and some adsorption selectivity for CO(2) over N(2).

14.
Inorg Chem ; 49(16): 7241-3, 2010 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-20690735

RESUMO

A novel Zn-Ni heterotrinuclear Schiff base compound bearing acacen(2-) moieties was constructed through the selective assembly of a chemosensor Schiff base zinc compound with a Ni(2+) ion. Its crystal structure not only clearly explains the binding mode between the chemosensor molecule and the detected metal ion but also represents the first trinuclear complex based on a symmetric acacen(2-) base Schiff base.

15.
Inorg Chem ; 48(18): 8659-61, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19689104

RESUMO

A rare in situ metal/ligand reaction has been observed during the assembly of a manganese-coordination polymer under solvothermal conditions, which leads to double C-C coupling on CHCl(3) involving cleavage of three C-Cl bonds and the formation of two new C-C bonds at the same carbon center.


Assuntos
Carbono/química , Clorofórmio/química , Manganês/química , Compostos Organometálicos/química , Polímeros/química , Ligantes , Espectroscopia de Ressonância Magnética , Metilação , Estrutura Molecular , Piridinas/química , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Temperatura
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