RESUMO
In the crystal structure of the title compound, {[Co(C11H9NSO5)(C10H9N3)]0.5C3H7NO·H2O} n or {[Co(dmtb)(dpa)]·0.5DMF·H2O} n (dmtb2- = 5-[(di-meth-yl-amino)-thioxometh-oxy]-1,3-benzene-dicarboxyl-ate and dpa = 4,4'-di-pyridyl-amine), an assembly of periodic [Co(C11H9NSO5)(C10H9N3)] n layers extending parallel to the bc plane is present. Each layer is constituted by distorted [CoO4N2] octa-hedra, which are connected through the µ 2-coordination modes of both dmtb2- and dpa ligands. Occupationally disordered water and di-meth-yl-formamide (DMF) solvent mol-ecules are located in the voids of the network to which they are connected through hydrogen-bonding inter-actions.
RESUMO
In the title compound, [Ag6(C12H10N3OS)6]·4C3H7NO, the hexa-nuclear complex mol-ecule lies about an inversion center. The six Ag atoms form a distorted octa-hedron, with Agâ¯Ag distances in the range 2.933â (1)-3.401â (1)â Å. Each Ag atom is surrounded by one N atom and two thiol-ate S atoms from two deprotonated 2-hy-droxy-1-naphthaldehyde thio-semi-carb-a-zone ligands. Each ligand coordinates three Ag atoms via a bridging thiol-ate S atom and a monodentate N atom, thus two Ag3S3 hexa-gonal rings are linked together. Two dimethyl-formamide solvent mol-ecules are located in four sets of sites with half-occupancy and form Oâ¯H-N hydrogen bonds to the complex mol-ecule. Intra-molecular O-Hâ¯N hydrogen bonds are also present. The discrete hexa-nuclear clusters are further linked through π-π inter-actions into layers parallel to (001), the shortest distance between the centroids of aromatic rings being 3.698â (2)â Å.
RESUMO
The title compound, (C(5)H(7)N(2))(2)[CdI(4)]·H(2)O, contains one [CdI(4)](2-) anion, two prontonated 4-amino-pyridine mol-ecules and one water mol-ecule in the asymmetric unit. In the anion, the Cd(II) atom is coordinated by four I atoms in a slightly distorted tetra-hedral geometry. The [CdI(4)](2-) anion and the water mol-ecule are bis-ected by a crystallographic mirror plane perpendicular to the c-axis direction, with the Cd(II) atom, two of the I atoms and the atoms of the water mol-ecule located on this plane. The crystal packing is stabilized by inter-molecular N-Hâ¯I, N-Hâ¯O and O-Hâ¯I hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.798â (3)â Å) between pyridine rings, which build up a three-dimensional network.
RESUMO
Eu3+-doped REVO4 nanphosphors were controllably synthesized by an EDTA-mediated hydrothermal method at 180 degrees C using RE(NO3)3 and Na3VO4 as precursors. The obtained products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectra (XPS), and photoluminescence spectroscopy (PL). The XRD results showed that the products were pure tetragonal structure and no other impurity phase appeared. The PL studies demonstrated Eu3+ ions doping effectively enhanced luminescent properties of LaxRE(1-x)VO4 and YxRE(1-x)VO4 nanoparticles, but EU3+ ions doping did not enhance luminescent properties of CexRE(1-x)VO4 (x not equal 0) nanoparticles. The prepared phosphors showed well-defined red luminescence due to radiative transitions from 5D0 to 7F(J) (J = 1,2) levels of Eu3+ ions, respectively. Furthermore, we reported Eu3+-doped CexRE(1-x)VO4 (x not equal 0) phases represented a new class of optically inactive materials.
RESUMO
In the title complex, [Cu(C6H4O2N)2]·2C9H6O6·2H2O, the Cu2+ ion lies on a center of inversion and coordinates with symmetry related pyridine nitro-gen and carboxyl oxygen atoms from two pyridine-2-carb-oxy-lic acid anions, giving rise to a square-planar coordination geometry. There are weak axial bonds between Cu and an O atom of a symmetry-related trimesic acid moieties [Cuâ¯O = 2.837â (2)â Å] The Cuâ¯O weak inter-actions and hydrogen bonds stabilize the whole structure.
RESUMO
Autophagy has a complex dual role in tumor survival or cell death owning to that is an evolutionarily conserved catabolic mechanism and provides the cells with a sustainable source of biomolecules and energy for the maintenance of homeostasis under stressful conditions such as tumor microenvironment. Hyperthermia is a rapidly growing field in cancer therapy and many advances have been made in understanding and applying the mechanisms of hyperthermia. The shallow oral and maxillofacial position and its abundant blood supply are favorable for the use of hyperthermia. However, the relationship between hyperthermia and autophagy has not been examined of oral squamous cell carcinoma (OSCC) in the tumor hypoxia microenvironment. Here, the expression level of autophagy relative genes is examined to explore autophagy effect on the responses of hyperthermia, hypoxia, and innutrition tumor microenvironment. It is founded that hyperthermia and hypoxia cause autophagy in starvation conditions; further, in hypoxia and innutrition tumor microenvironment, hyperthermia combines YC-1 and 3-MA could inhibit HIF-1α/BNIP3/Beclin1 signal pathway and decrease the secretion of HMGB1; moreover, the cell apoptosis rate increases with an inhibited of cell migration capacity. Thus, the present study demonstrated that combined use of YC-1 and 3-MA might increase the death of tumor cells in physiological and hyperthermic conditions, which could be relevant with the inhibition of autophagy in OSCC tumor cells under hypoxia microenvironment in vitro, which offers new insight into the therapy of OSCC and its application in treating others study carcinomas.
RESUMO
OBJECTIVE: To investigate whether hyperthermia, chemotherapy and thermo-chemotherapy could trigger the expression of damage-associated molecular patterns (DAMPs). METHODS: The optimal working concentration of pingyangmycin (PYM) was detected by CCK-8 assay, and temperatures of 39, 42, and 45 â were applied to the oral squamous cell carcinoma CAL27, SCC-15, and Tca8113 cell lines. The effects of different treatments on the apoptosis, calreticulin (CRT) membrane expression and high-mobility group box 1 (HMGB1) secretion of the cells were detected by using Annexin V/propidium iodide (PI), flow cytometry and enzyme-linked immunosorbent assay (ELISA) assay. SPSS 20.0 software was used for statistical analysis. RESULTS: Both hyperthermia and chemotherapy could increase the membrane expression of CRT and the secretion of HMGB1, and furthermore, thermo-chemotherapy group showed significantly increased in apoptosis, CRT membrane expression rate and HMGB1 secretion compared with chemotherapy group, and the difference was statistically significant (P<0.05). CONCLUSIONS: Hyperthermia, chemotherapy and thermo-chemotherapy could induce oral squamous cell carcinoma cells succumb to death, and at the same time, they can effectively induce the membrane expression of CRT, and promote the secretion of HMGB1. Moreover, thermo-chemotherapy is significantly better than that of chemotherapy alone in the induction of cell apoptosis and DAMPs expression.
Assuntos
Carcinoma de Células Escamosas , Proteína HMGB1 , Neoplasias Bucais , Apoptose , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Humanos , Neoplasias Bucais/terapiaRESUMO
In the centrosymmetric dinuclear title compound, [Ag(2)(C(36)H(26)N(8))(2)](PF(6))(2)·2C(2)H(3)N, the Ag(+) ion is bound to four N atoms from two 1,2-diphenyl-N,N'-bis-(di-2-pyridyl-methyl-eneamino)ethane-1,2-diimine ligands in a distorted tetra-hedral geometry. The ligand adopts a twist conformation, coordinating two metal centers by three pyridyl N atoms and one imine N atom and spanning two Ag(+) ions, resulting in the formation of a helical dimeric structure.
RESUMO
The new ligand 1-(1,2,4-triazol-4-ylimino-meth-yl)-2-naphthol (L) and the title silver(I) complex, namely bis-[µ-1-(1,2,4-triazol-4-ylimino-meth-yl)-2-naphthol]bis-{[1-(1,2,4-triazol-4-yl-imino-meth-yl)-2-naphthol]silver(I)} dinitrate monohydrate, [Ag(2)(C(13)H(10)N(4)O)(4)](NO(3))(2)·H(2)O, were synthesized. Each silver center in the dimeric complex (related by an inversion centre) is coordinated by two bridging L ligands and one additional L ligand in a monodentate fashion, exhibiting a distorted trigonal-planar coordination. The discrete dimers are further linked through O-Hâ¯O hydrogen bonds and weak π-π stacking inter-actions [the shortest atom-atom separation is ca 3.46â Å between the parallel stacking pairs]. Intramolecular O-Hâ¯N hydrogen bonds are also present.
RESUMO
In title compound, {(C(2)H(10)N(2))(0.5)[In(C(2)O(4))(2)]·2H(2)O}(n), the unique In(III) ion is coordinated by eight O atoms from four oxalate ligands in a distorted square-anti-prismatic environment. The doubly bis-chelating oxalate ligands act as bridging ligands connecting symmetry-related In(III) ions and forming a three-dimensional open framework structure. Ethyl-enediammonium cations and water mol-ecules occupy the voids within the structure. The unique ethyl-enediammonium cation and one water mol-ecule both lie on a twofold rotation axis. One of the other two water mol-ecules residing on general crystallographic sites was refined as disordered with half occupancy. In the crystal structure, cations and water mol-ecules are linked to the anionic framework via inter-molecular O-Hâ¯O and N-Hâ¯O hydrogen bonds.
RESUMO
In the title compound, {[Zn(C(9)H(9)N(5))(2)(H(2)O)(2)](ClO(4))(2)}(n), the Zn(II) ion lies on an inversion center and is coordinated by two triazolyl N atoms and two pyridyl N atoms from four symmetry-related N-1-(3-pyrid-yl)ethyl-idene-4H-1,2,4-triazol-4-amine (L) ligands and two O atoms from coordinated water mol-ecules in a slightly distorted octa-hedral environment. Each L ligand bridges symmetry-related Zn(II) ions, forming a two-dimensional layer with a (4,4) grid. In the crystal structure, inter-molecular O-Hâ¯O hydrogen bonds connect perchlorate counter-anions to the layers.
RESUMO
The asymmetric unit of the title compound, (C(8)H(8)N(5))(2)[Ce(NO(3))(5)(H(2)O)(2)], contains one independent protonated 4-pyridyl-methyl-eneamino-1,2,4-triazole cation and half of a centrosymmetric [Ce(NO(3))(5)(H(2)O)(2)](2-) anion. The Ce atom coordinated by five NO(3) (-) anions and two water mol-ecules, exhibiting a distorted 10-coordination. In the crystal structure, inter-molecular O-Hâ¯N and N-Hâ¯O hydrogen bonds result in the formation of a supramolecular structure.
RESUMO
Symmetric breaking of silver double helicates through spontaneous crystallization was achieved via incorporation of C-H...pi and pi-pi stacking interactions of achiral ligands consisting of several aromatic rings.
Assuntos
Prata/química , Dicroísmo Circular , Hidrogênio/química , Ligantes , Modelos Moleculares , Estrutura Molecular , EstereoisomerismoRESUMO
Four novel polyoxovanadium borates with [(VO)12O6B18O42], namely (enH2)6 H3 [(VO)12O6B18O42].13H2O(1), [Ni (en)2]6 H3 [(VO)12 O6B18O42].8H2O(2), [Cu(en)2]5 H3 [(VO)12 O6B18 O42] [B(OH)3]2. 16H20(3) and(enH2)4 Na4H3 [(VO)12 O6B18O42].8H2O(4), were synthesized. The relationship between their properties and structures were studied by using FTIR, UV-Vis DRS and fluorescence etc. Among these compounds, compound (1) possesses isolated [(VO)12O6B18O42] cage, there is a ring of B18O42 sandwiched between two vanadium-oxygen clusters V6O18 by eighteen B--(micro3--O)--V bonds, while compound (2) is rather six [Ni(en)2], each connected with the B18O42 ring by two Ni--(micro3--O)--B. In compounds (3) and (4), the anion clusters [(VO)12 O6B18O42]13- are connected with [Cu(en)2]2+ and Na+ , respectively. Thus, the compounds (3) and (4) are extended to an infinite two-dimensional network structure, respectively. These characteristic vibrational frequencies of polyoxovanadium borates are related to the structures of these compounds. In UV/Vis DRS spectra, there are two characteristic peaks of polyoxometalates at 205 and 260 nm, respectively. The fluorescence spectra of these four compounds have been studied, and they have emission peaks at 415 nm excited by 310 nm which are caused by Omicro-->Mo. The fluorescence lifetimes of these compounds have been studied.
Assuntos
Boratos/química , Análise Espectral , Compostos de Vanádio/química , Boratos/síntese química , Cobre/química , Cristalização , Modelos Moleculares , Estrutura Molecular , Níquel/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Vanádio/síntese químicaRESUMO
Polyoxometalate-based metal-organic frameworks {[Gd(dpdo)(4)(H(2)O)(3)](PMo(12)O(40))(H(2)O)(2)CH(3)CN}(n) (2), {[Dy(dpdo)(4)(H(2)O)(3)](PMo(12)O(40))(H(2)O)(20CH(3)CN}(n) (3), {[Gd(dpdo)(4)(H(2)O)(3)](H(3)O)(SiMo(12)O(40))(dpdo)(0.5)(CH(3)CN)(0.5) (H(2)O)(3)}(n) (4), {[Ho(dpdo)(4)(H(2)O)(3)](H(3)O)(SiMo(12)O(40))(dpdo)(0.5)(CH(3)CN)(0.5)(H(2)O)(3)}(n) (5), {[Ni(dpdo)(2)(CH(3)CN) (H(2)O)(2)](2)(SiMo(12)O(40))(H(2)O)(2)}(n) (6), and {[Ni(dpdo)(3)](4)(PW(12)O(40))(3)[H(H(2)O)(27)(CH(3)CN)(12)]}(n) (7) (where dpdo is 4,4'-bipyridine-N,N'-dioxide) were constructed via self-assembly by embedding Keggin-type polyanions within the intercrystalline voids as guests or pillars. Compounds 2 and 3 are isomorphic and exhibit three-dimensional (3D) noninterwoven 64 frameworks with distorted-honeycomb cavities occupied by the polyanions. Compounds 4 and 5 are comprised of 3D noninterwoven frameworks formed by linking the adjacent folded sheets through hydrogen bonds and pi-pi stacking interactions relative to the free isolated dpdo ligand. Compound 6 is a pillar-layered framework with the [SiMo(12)O(40)](4-) anions located on the square voids of the two-dimensional bilayer sheets formed by the dpdo ligands and nickel(II) ions. Compound 7 is a 3D metal-organic framework formed by nickel(II) and 4,4'-bipyridine-N,N'-dioxide with the globular Keggin-structure [PW(12)O(4)](3-) anion as the template. A large protonated water cluster H(+)(H(2)O)(27) is trapped and stabilized within the well-modulated cavity.
RESUMO
A series of Ag(I) coordination compounds, from one-dimensional chains to 3D porous frameworks, were achieved from N,N'-bis[1-(2-pyrazinyl)ethylidene]benzil dihydrazone, L, via self-assembly, using helicates as effective secondary building units. Compound 2 [(Ag(2.75)L)(NO(3))(2.75)] was comprised of two opposite-handed 3D frameworks formed by connecting the 4(1) helical chains into (10(3)-b) nets. The pairs of the racemic 3D frameworks were connected through additional silver(I) centers and entangled each other forming a racemic 3D net. Compound 3 [(Ag(13)L(8))(BF(4))(13)(H(2)O)(12)] was comprised of a 3D framework that was constructed from double-helical building intermediates Ag(2)L(2) with one-dimensional infinite chains being threaded into the large voids of a 3D framework to form a weave structure. The ladder-like chains in compound 4 [(Ag(3)L(2))(ClO(3))(3)(CH(3)OH)(2)(CH(3)CN)] were formed by the addition of excess NaClO(3) into the methanol solution containing AgNO(3) and the ligand L, and the zigzag chains in compound 5 [(Ag(2)L(2))(ClO(4))(2)(CH(3)CN)(2)] were constructed by the addition of excess NaClO(4) into an acetonitrile solution containing AgNO(3) and the ligand L.
Assuntos
Polímeros/química , Cátions , Cristalografia por Raios X/métodos , Hidrazonas/química , Ligantes , Modelos Químicos , Conformação Molecular , Estrutura Molecular , Conformação Proteica , Pirazinas/químicaRESUMO
Chiral aggregation and spontaneous resolution of thiosemicarbazone metal complexes MnL2 (1 and 1') (HL = acetylpyrazine thiosemicarbazone) were achieved through cooperation of hydrogen bonding and pi-pi stacking interactions. Compound 1 crystallized in a chiral space group P4(1)2(1)2 and the molecules exhibited lambda-configuration. Head-to-tail pyrazine-amino hydrogen bonding linked the molecules together presenting a two-dimensional homochiral sheet. The interlayer pi-pi stacking interactions linked the layers in a homochiral array and extended the 2D homochirality to a three-dimensional network. Compound 1 crystallized in space group P4(3)2(1)2, the opposite handedness of P4(1)2(1)2. The molecules, the two-dimensional hydrogen-bonded sheets and the three-dimensional network all exhibited the opposite chiralities to those of 1. Solid state CD spectra measurements confirmed the occurrence of spontaneous resolution of MnL2 and demonstrated that one of the enantiomers of the compound was always in excess. The zinc complexes (2 and 3) and nickel complex 4 crystallized in the chiral space group P4(3)2(1)2. Similar two-dimensional pyrazine-amine hydrogen bonded chiral sheets and three-dimensional networks were found in the crystal packing patterns. The cadmium complex 5 crystallized in a chiral space group P2(1)2(1)2(1), however, it exhibited a similar chiral packing pattern. The only difference was that enlarged Cd-S and Cd-N bond lengths induced the potential 4(1) symmetry. All results indicated that the supramolecular synthon, the cooperation of the pyrazine-amino hydrogen bonding and the pi-pi stacking interactions, were robust enough so that the orientation of the molecules in the solid state could be predicted to a reasonable degree of accuracy.