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1.
BMC Cancer ; 24(1): 353, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504158

RESUMO

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer.


Assuntos
Neoplasias da Mama , Carcinoma , Humanos , Feminino , Neoplasias da Mama/genética , Apoptose , Mama , Proliferação de Células/genética , Prognóstico , Microambiente Tumoral/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética
2.
Shanghai Kou Qiang Yi Xue ; 31(3): 248-254, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-36204951

RESUMO

PURPOSE: To develop an effective machine learning method for estimation of Ki-67 cell proliferation index. METHODS: Oral squamous cell carcinoma(OSCC) slices were selected for Ki-67 immunohistochemical staining. The digital pathology images were obtained through whole-slide imaging technology. Variable threshold method based on local statistics was applied to preprocess the images, aiming at reducing the noise in the images. Adaptive threshold method was used to remove the irrelevant light-colored background area in the image, retaining the nucleus part. A threshold method in space was applied to differentiate brown from blue content. Finally, the proliferation index was estimated and compared with manual and the color deconvolution method by paired sample t test and spearman correlation coefficients with SPSS 24.0 software package. RESULTS: A new nucleus detection and classification method was established, which can process pathologic images of different sizes, and effectively detect immunohistochemical brown positive cells and blue negative cells. There was no significant difference between this algorithm and manual counting(P>0.05), but the speed was faster. The calculation efficiency advantage was more obvious when processing a large image, and the detection result of Ki-67 proliferation index was better than the commonly used color deconvolution method(P<0.05). CONCLUSIONS: The automatic nucleus quantitative analysis method developed in this study can analyze Ki-67 staining of the nucleus in OSCC cells efficiently and calculate the proliferation index, which can be used for auxiliary diagnosis in pathology.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Algoritmos , Carcinoma de Células Escamosas/diagnóstico , Proliferação de Células , Humanos , Processamento de Imagem Assistida por Computador/métodos , Antígeno Ki-67/análise , Neoplasias Bucais/diagnóstico
3.
Org Biomol Chem ; 19(7): 1610-1615, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33528484

RESUMO

Highly enantiopure and bioactive δ-valerolactones and pyrazolones, bearing α-all-carbon quaternary stereocentres, were successfully and sequentially prepared via a one-pot procedure starting from readily available, inexpensive materials, catalysed by a new chiral squaramide under mild reaction conditions. An organocatalytic Michael reaction afforded the valerolactones, while a one-pot Michael-hydrazinolysis-imidization cascade yielded the pyrazolones. This procedure is economically efficient and environmentally benign.

4.
Dalton Trans ; 48(13): 4324-4332, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30860232

RESUMO

A series of dinuclear dysprosium complexes bridged by pyridine-NO ligands with formula [Ln2(BTA)6(pyNO)2] (1Dy, Ln = Dy, 1Y, Ln = Y and 1Gd, Ln = Gd) (BTA = benzoyltrifluoroacetone, pyNO = pyridine-N-oxide) were structurally and magnetically characterized. The X-ray crystallographic analyses of the structures revealed that the NO group serves as the effective bridge to link two Dy(iii) centers and the periphery ß-diketonate (BTA) ligands complete the rest of the coordination sphere. The dynamic magnetic measurements revealed that complex 1Dy displayed significant zero-field single-molecule magnetic (SMM) behaviour with 72 K energy barrier and 2.5 K hysteresis temperature. In order to extend this dinuclear system, double N-oxide bridged ligand 4,4'-bpdo(4,4'-bipyridine-N,N'-dioxide) was used, and consequently, a series of one-dimensional chain complexes possessing repeated [Ln2(BTA)6(pyNO)2] units were synthesized with formula [Ln2(BTA)6(4,4'-bpdo)]n·2EtOH (2Dy, Ln = Dy, 2Y, Ln = Y and 2Gd, Ln = Gd). The AC magnetic susceptibility measurements revealed that complex 2Dy exhibited significant zero-field slow magnetic relaxation behavior with a higher effective energy barrier of 87 K and a hysteresis temperature of 3 K than 1Dy albeit the separation between the repeated units is large.

5.
Dalton Trans ; 48(15): 4931-4940, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30912784

RESUMO

A tetradentate 8-hydroxyquinoline-based acyl hydrazone ligand (HL1 = 8-hydroxyquinoline-2-carboxaldehyde-(aminourea)hydrochloride) was elaborately used to construct a mononuclear dysprosium complex DyCl3HL1·CH3OH (1) with a nearly ideal pentagonal bipyramid coordination geometry (D5h) surrounding the Dy(iii) ion to achieve the significant performance of single-molecule magnets (SMMs). Meanwhile, the isolated high local symmetry center was successfully kept intact and further bridged to a series of double bipyramid systems by two phenolic oxygen atoms of the acyl hydrazone ligands (HL1 and HL2 = 8-hydroxyquinoline-2-carboxaldehyde-(benzoyl)hydrazine), with the formulae [Dy2Cl4(L1)2(CH3OH)2]·4C5H5N (2) and [Dy2Cl4(L2)2]·2CH3CN (3). In addition, the monodentate co-ligand anion was replaced by a larger sterically hindered ligand and a bidentate monovalent ß-diketonate anion to generate [Dy2(tfo)4(L2)2(EtOH)2] (4), [Dy2(tta)4(L2)2(EtOH)2]·2(EtOH) (5) and [Dy2(dbm)4(L2)2(EtOH)2] (6) (tfo = trifluoromethanesulfonic acid, dbm = dibenzoylmethane, tta = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione) with eight-coordinate geometry. Strikingly, the dynamic magnetic measurements revealed that complexes 1-3 did not display the expected significant SMM performance albeit they had high local symmetry. In combination with ab initio calculation, the alignment of the coordination symmetric axis and the magnetic easy axis dominates the molecular magnetic anisotropy, and the magnetic easy axis could be modulated by the distribution of coordination atoms with different electrostatic properties.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-779476

RESUMO

Objective To study the pollution and source apportionment differences of different periods PM2.5 in the residential community of suburb in Tianjin City during heating and non-heating periods. Methods From 2015 to 2016, daytime and nighttime PM2.5 samples were collected at a community in the suburb of Tianjin. The mass concentration of PM2.5 samples and major chemical components in PM2.5, including metal elements, polycyclic aromatic hydrocarbons (PAHs) and inorganic water-soluble ions were monitored. Positive matrix factorization (PMF) model was used to apportion potential sources of metal elements, PAHs and inorganic water-soluble ions in daytime and nighttime PM2.5. Results In the heating period, the concentrations of some metal elements of suburban residential community were higher in the daytime than in the nighttime. In the non-heating period, the concentrations of some PAHs and inorganic water-soluble ions of suburban residential community were higher in the nighttime than in the daytime. Meanwhile, the concentrations of some metal elements were greater in the daytime than in the nighttime. When in heating period, the main source of PM2.5 in the suburban residential community was coal combustion during daytime and its source contribution rate was 50.1% while secondary aerosol and fuel combustion emissions of gasoline and diesel vehicles were main sources during nighttime and their source contribution rates were 41.0% and 35.9%. The principal source of daytime PM2.5 in the suburban residential community was indoor activity emissions during non-heating period, and secondary aerosol was main source during nighttime and their source contribution rates were 29.8% and 31.1%. Conclusions The pollution status of PM2.5 in residential communities of suburban is serious, and the source apportionment of day and night PM2.5 samples has different in different heating periods.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-778709

RESUMO

Objective To explore the effect of air pollution on children’s respiratory diseases in Tianjin, so as to provide reference for the prevention and control of diseases. Methods Conditional Logistic regression model of single pollutant and multiple pollutants was used to estimate the relationships between air pollutants concentration and children’s respiratory system diseases. Results Conditional Logistic regression model of single pollutant conditions showed that the excess risk (ER) effects and 95% CI of NO2, PM2.5, PM10 and CO appeared were 2.823%(2.581-3.065), 0.476%(0.382-0.569), 0.437%(0.368-0.506), 22.263%(15.449-29.478), respectively. Logistic regression analysis of multiple pollutants conditions showed that NO2 exposure had the greatest effect on children’s respiratory diseases in cold season, and the excess risk (ER) was 7.395%(6.595-8.202). Conclusion The elevated daily average concentration of NO2, PM10, PM2.5, and CO can increase the risk of children’s respiratory diseases.

8.
Inorg Chem ; 57(14): 8065-8077, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-29965732

RESUMO

A series of Salen-type Zn(II)-Dy(III) complexes [L1Zn(II)ClDy(III)(acac)2]·H2O (1), [L1Zn(II)BrDy(III)(acac)2]·H2O (2), [L1Zn(II)(H2O)Dy(III)(acac)2]·CH2Cl2·PF6 (3), [L2Zn(II)(H2O)Dy(III)(acac)2]·PF6 (4), and Co(III)-Dy(III) complexes [L1Co(III)Br2Dy(III)(acac)2]·CH2Cl2 (5), [L2Co(III)Cl2Dy(III)(acac)Cl(MeO)] (6), [L2Co(III)Cl2Dy(III)(acac)Cl(H2O)] (7), and [L2Co(III)Cl2Dy(III)(NO3)2(MeO)] (8) heterobinuclear single-molecule magnets (SMMs) were synthesized and magnetically characterized. These complexes were constructed by incorporating diamagnetic Zn(II) and Co(III) ions with acetylacetone (acac) and compartmental Schiff-base ligands (H2L1 = N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine; H2L2 = N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-diaminocyclohexane). In the Zn(II)-Dy(III) (1-4) system, the coordination environments of the Dy(III) ions are nearly identical, but the apical coordination atom to the Zn(II) ion is different. Complexes 1, 2, and 4 displayed no magnetic relaxation in the absence of external magnetic field, but complex 3 displayed more pronounced SMM behavior with a relaxation energy barrier Ueff/ kB 38 K and magnetic hysteresis at 1.8 K. The SMM performances of 5, 6, and 7 were enhanced significantly by incorporating an octahedral Co(III) instead of square-pyramidal Zn(II) and replacing one of acac- group around Dy(III) ion by a neutral O atom, displaying Ueff of 167, 118, and 75 K as well as magnetic hysteresis up to 3.5 K. These studies indicated that the remote diamagnetic Zn(II) and Co(III) ions played a key role, and the SMM properties were very strongly related to the special coordination atoms configuration around Dy(III) ion. When this coordination configuration around was broken as 8 exhibited, however, it resulted in a dramatically decreased SMM performance. From this work, the key factors that significantly affect the SMM performance of these heteronuclear Zn(II)/Co(III)-Dy(III) SMMs are unambiguously presented.

9.
Chem Asian J ; 13(13): 1725-1734, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29663704

RESUMO

Crystal structures, single-molecule magnetic behavior, and ab initio calculations of four new phenoxo-bridged dinuclear dysprosium complexes and their gadolinium(III) analogues are explored. Complexes [Dy2 (DMOMP)2 (DBM)4 ]2 ⋅CHCl3 (1; DMOMP=1-methyl-3,5-dimethoxy-4-hydroxybenzene, DBM=1,3-diphenylpropane-1,3-dione); [Dy2 (DMOAP)2 (DBM)4 ]2 ⋅CHCl3 (2; DMOAP=syringaldehyde); Dy2 (DMOEP)2 (DBM)4 (3; DMOEP=methyl syringate); and solvent-free Dy2 (DMOMP)2 (DBM)4 (4), which is obtained by the transformation of single crystal into single crystal from 1, have nearly identical core structures and only differ in the substituents at the para position of the phenol moieties of the bridging ligand. In this system, the electronic effects are efficiently implemented to significantly modify the ligand field strength and exchange coupling by modulating the substituents on the phenol backbone. The effective energy barrier (Ueff ) of magnetization reversal is improved significantly to fivefold magnitude, at most, and the hysteresis temperature up to 3.5 K by deliberately using the electron-withdrawing substituent to replace the electron-donating one. The origin of the two relaxation processes in 1 is mostly attributed to the existence of two molecules in one unit, which is illuminated by means of the transformation of single crystal into single crystal.

11.
Dalton Trans ; 46(25): 8259-8268, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28613300

RESUMO

The synthesis, structural characterization and magnetic properties of four heterometallic complexes with formulas Ln2M(OQ)8 [Ln(iii) = Dy, M(ii) = Ca (1), Mg (2); Ln(iii) = Er, M(ii) = Ca (3), Mg (4); HOQ = 8-hydroxyquinoline] are reported. Complexes display a perfectly linear arrangement of three metal ions involving two terminal Ln(iii) ions and one central alkaline earth M(ii) ion, and they are bridged by three phenolato oxygen atoms from three 8-hydroxyquinoline ligands. Direct-current (dc) magnetic susceptibility studies show that there exists a long-range ferromagnetic (FM) interaction between two f-electronic centers in Dy-based complexes 1 and 2 albeit they are separated by diamagnetic alkaline earth ions, and the FM interaction has been successfully reproduced by ab initio calculations. Alternating current (ac) magnetic susceptibility measurements indicate that complexes 1 and 2 exhibit significant single-molecule magnet (SMM) behaviors. This is mostly attributed to the parallel magnetic axes of individual Dy(iii) sites aligning closely to the Dy-M-Dy direction, and the linearly extending magnetic susceptibility tensors of each ion lead to the FM interaction. The dc and ac susceptibility studies of the intramolecularly diluted complexes reveal that the f-f coupling suppresses the QTMs significantly in the absence of the external magnetic field.

12.
Org Lett ; 19(10): 2634-2637, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28481099

RESUMO

The enantioselective cross-aldol reaction between o-hydroxyacetophenones and trifluoromethyl ketones catalyzed by chiral thiourea organocatalysts is reported. Gram-scale synthesis of the cross-aldol product was carried out, with no decrease in the yield and enantioselectivity. Furthermore, the cross-aldol products thus prepared were used in the preparation of medicinally interesting 3,5-diaryl-5-trifluoromethyl-2-isoxazoline and ß-trifluoromethyl-ß-tertiary hydroxy acid ester with high yield and enantiopurity.

13.
Dalton Trans ; 45(21): 8790-4, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27143486

RESUMO

Two dinuclear dysprosium complexes with the Dy(iii) ions bridged by the neutral bipyrimidine (BPYM) ligand were synthesized and magnetically characterized. They crystallized in a monoclinic and triclinic crystal system, respectively, with almost the same structural core, only differing in the lattice solvent molecules. Alternating current (ac) susceptibility measurements revealed that they exhibit significant slow relaxation of magnetization until 25 K in the absence of a dc field. The single and double relaxation processes were assigned to one and two types of Dy(iii) environments in the two dimmers, respectively, with barriers of 266 and 345 K under zero field conditions. The magnetic hysteresis loops of 1 and 2 were both observed up to 2.5 K.

14.
Dalton Trans ; 45(9): 3863-73, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26905041

RESUMO

A series of HMq-bridged dinuclear dysprosium complexes, namely, [Dy(acac)2(CH3OH)]2(µ-HMq)2 (1), [Dy(DBM)2]2(µ-HMq)2(n-C6H14) (2), [Dy(hmac)2]2(µ-HMq)2 (3) and [Dy(hfac)3]2(µ-HMq)2 (4) (HMq = 2-methyl-8-hydroxyquinoline, acac = acetylacetone, DBM = dibenzoylmethane, hmac = hexamethylacetylacetonate and hfac = hexafluoroacetylacetonate), were structurally and magnetically characterized. X-ray crystallographic analyses of the structures reveal that HMq serves as the effective bridge to link two Dy(III) centers by means of the phenoxyl oxygen and nitrogen atoms and the periphery ß-diketonate ligands complete the coordination sphere by bidentate oxygen atoms. The different substituents on the ß-diketonate terminal lead to different coordination models mostly due to the steric hindrance of these substituents, and the electron-withdrawing or donating effects likely influence the strength of the ligand fields and the Dy(III) ion anisotropy. Measurements of alternating-current (ac) susceptibility on complexes 1-4 reveal that complexes 3 and 4 display significant zero-field single-molecule magnetic (SMM) behavior with barrier energy Ueff/kB = 14.8 K, τ0 = 1.8 × 10(-5) s and Ueff/kB = 9.2 K, τ0 = 1.7 × 10(-5) s, respectively, whereas 1 and 2 exhibit field-induced SMM behavior, and these differences are attributed to the alteration on the periphery ß-diketonate ligands. Their distinct slow magnetic relaxation behaviors were related to their different individual Dy(III) ion magnetic anisotropy and intramolecular coupling, which were confirmed by ab initio calculations.

15.
Dalton Trans ; 45(6): 2674-80, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26744071

RESUMO

Three complexes with formula {Dy(q)2(L)}2(µ3-OH)2{Dy(q)(L)}2(solvents) (where q = 8-quinolinolate; L = acetylacetone (acac) with (CH2Cl2)2 = solvent (1), 1,3-diphenyl-1,3-propanedione (DBM) and (CH2Cl2)2 = solvent (2), and hexafluoroacetylacetone (hfac) and CHCl3 = solvent (3)) were structurally and magnetically characterized. They have similar Dy4 structural cores bridged by N and O atoms from 8-quinolinolate, and only differ in the peripheral ß-diketonate ligands. The variable-frequency and temperature alternating-current (ac) magnetic susceptibility measurements reveal that complexes 1 and 2 display significant zero-field single-molecule-magnet (SMM) behavior, while complex 3 exhibits the field-induced SMM behavior, albeit they possess the nearly same primary coordination sphere. The ac susceptibility measurement on the diluted samples verified that their relaxation was of purely molecular origin, and their distinct slow magnetic behaviors were related to the replacement of the peripheral ß-diketonate ligand, which is responsible for their different individual Dy(iii) ions' magnetic anisotropy and intramolecular coupling, as confirmed by ab initio calculation.

16.
Chem Sci ; 7(1): 684-691, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28791111

RESUMO

A series of mononuclear lanthanide Zn-Dy-Zn type single-molecule magnets (SMMs) were synthesized and magnetically characterized. The four molecules ([Zn2(L1)2DyCl3]·2H2O (1), [Zn2(L1)2Dy(MeOH)Br3]·3H2O (2), [Zn2(L1)2Dy(H2O)Br2]·[ZnBr4]0.5 (3) and [Zn2(L2)2DyCl3]·2H2O (4)) all display remarkable magnetic relaxation behavior with a relatively high energy barrier and hysteresis temperature, despite possessing a low local geometry symmetry of the center Dy(iii) ions. Ab initio studies revealed that the symmetry of the charge distribution around the Dy(iii) ion is the key factor to determine the relaxation of the SMMs. The four complexes orient their magnetic easy axes along the negative charge-dense direction of the first coordination sphere. The entire molecular magnetic anisotropy was therefore controlled by a single substituent atom in the hard plane which consists of five coordination atoms (perpendicular to the easy axis), and the lower charge distribution on this hard plane in combination with the nearly coplanarity of the five coordination atoms ultimately lead to the prominent magnetic slow relaxation. This offers an efficient and rational method to improve the dynamic magnetic relaxation of the mononuclear lanthanide SMMs that usually possess a low local geometry symmetry around the lanthanide(iii) center.

17.
Org Biomol Chem ; 14(2): 724-728, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26575990

RESUMO

The regioselective unilateral additions of Grignard reagents to acyclic or cyclic ß-diketones were effectively promoted by sub-stoichiometric amounts of i-PrMgCl to afford ß-tertiary hydroxyl ketones or 3-substituted cyclic-2-enones, respectively. Also, the addition of Grignard reagents to acyclic ß-diketones followed by a reaction with cyclic ß-diketones in a one-pot process was put forward. The reaction mechanism was discussed in detail to explain the high regioselectivity via chemical experiments, hydrogen-deuterium exchange and mass spectrometry.

18.
Dalton Trans ; 42(37): 13397-403, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23887476

RESUMO

Three dinuclear [Ln2H2OL(1)2(acac)2]·solvent (1, Ln = Gd, solvent = 2CH2Cl2; 2, Ln = Tb, no solvent; 3, Ln = Er, solvent = (C2H5)2O), and two tetranuclear lanthanide clusters [Ln4(µ3-OH)2L(2)2(acac)6]·2(solvent) (4, Ln = Tb, solvent = CH3OH; 5, Ln = Dy, solvent = CH3CN) were characterized in terms of structure, fluorescence and magnetism. The dinuclear lanthanide complexes were constructed by a rigid salen-type ligand H2L(1) = N,N'-bis(salicylidene)-o-phenylenediamine and ß-diketonate (acac = acetylacetonate) ligands, while the tetranuclear clusters were formed from the flexible ligand H2L(2) = N,N'-bis(salicylidene)-1,2-ethanediamine. Crystal structure analysis indicates that the rigid ligand favors the double-decker sandwich structure (Ln2L(1)2), in which the two lanthanide ions have different coordination numbers and geometry, while the more flexible ligand (H2L(2)) leads to planar tetranuclear clusters. The relationship between their respective magnetic anisotropy and ligand-field geometries and their fluorescence properties was investigated. The Dy and Tb-containing clusters exhibit typical visible fluorescence properties, and single-molecule magnet behavior is seen in complex 5.


Assuntos
Etilenodiaminas/química , Fluorescência , Hidroxibutiratos/química , Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/química , Pentanonas/química , Ligantes , Fenômenos Magnéticos , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química
19.
Artigo em Inglês | MEDLINE | ID: mdl-22763323

RESUMO

A biphenyl-linked bis-ß-diketone ligand, 3,3'-bis(3-phenyl-3-oxopropanol)biphenyl (BPB) has been prepared for the syntheses of a series of dinuclear lanthanide complexes. The ligand bears two benzoyl ß-diketonate sites linked by a 3,3'-biphenyl spacer. Reaction of the doubly negatively charged bis-bidenate ligand with lanthanide ions forms triple-stranded dinuclear complexes Ln(2)(BPB)(3) (Ln=Nd (1), Sm (2), Eu (3), Yb (4) and Gd (5)). Electrospray mass spectrometry is used to identify the formation of the triple-stranded dinuclear complexes 1-5, which have been further characterized by various spectroscopic techniques. The complexes display strong visible and NIR luminescence upon excitation at ligands bands around 360 nm, depending on the choice of the lanthanides, and the emission quantum yields and luminescence lifetimes of 2-3 have been determined. It shows that the biphenyl-linked ligand BPB is a more efficient sensitizer than the monodiketone ligand DBM (dibenzoylmethane), through the comparisons of Ln(2)(BPB)(3) and Ln(DBM)(3) on their photoluminescent properties.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Cetonas/química , Elementos da Série dos Lantanídeos/química , Elementos da Série dos Lantanídeos/síntese química , Luminescência , Acetona/química , Ligantes , Espectroscopia de Ressonância Magnética , Soluções , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): m589, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590099

RESUMO

In the title hetero-dinuclear complex, [CuSm(C(22)H(24)N(2)O(4))Cl(3)(CH(3)OH)(2)], the Cu(II) cation is N,N',O,O'-chelated by a 6,6'-dimeth-oxy-2,2'-[cyclo-hexane-1,2-diylbis(nitrilo-methanylyl-idene)]diphenolate ligand, and one Cl(-) anion further coordinates to the Cu(II) cation to complete the distorted square-pyramidal coordination geometry, while the Sm(III) cation is chelated by four O atoms from the same ligand, and is further coordinated by two methanol mol-ecules and two Cl(-) anions in an bicapped trigonal-prismatic geometry. Intra- and inter-molecular O-H⋯Cl hydrogen bonds are present in the structure.

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