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1.
Adv Sci (Weinh) ; 11(13): e2309388, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38269649

RESUMEN

Cuproptosis, an emerging form of programmed cell death, has received tremendous attention in cancer therapy. However, the efficacy of cuproptosis remains limited by the poor delivery efficiency of copper ion carriers. Herein, copper complex nanoparticles (denoted as Cu(I) NP) are developed that can efficiently deliver copper complex into cancer cells to induce cuproptosis. Cu(I) NP demonstrate stimulus-responsive release of copper complexes, which results in mitochondrial dysfunction and promotes the aggregation of lipoylated dihydrolipoamide S-acetyltransferase (DLAT), leading to cuproptosis. Notably, Cu(I) NP not only induce cuproptosis, but also elicit robust immune responses to suppress tumor growth. Overall, this study provides a promising strategy for cuproptosis-based cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Cobre , Inmunoterapia , Apoptosis , Neoplasias/terapia
2.
Med Rev (2021) ; 3(1): 4-30, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37724108

RESUMEN

The complexity of the tumor microenvironment (TME) severely hinders the therapeutic effects of various cancer treatment modalities. The TME differs from normal tissues owing to the presence of hypoxia, low pH, and immune-suppressive characteristics. Modulation of the TME to reverse tumor growth equilibrium is considered an effective way to treat tumors. Recently, polymeric nanomedicines have been widely used in cancer therapy, because their synthesis can be controlled and they are highly modifiable, and have demonstrated great potential to remodel the TME. In this review, we outline the application of various stimuli responsive polymeric nanomedicines to modulate the TME, aiming to provide insights for the design of the next generation of polymeric nanomedicines and promote the development of polymeric nanomedicines for cancer therapy.

3.
Environ Res ; 203: 111873, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34411548

RESUMEN

A series of rare earth complexes containing (α-PW12O40)3- and PO ligand are synthesized by water bath in 70 °C, [Ln(OPPh3)4(H2O)3](PW12O40)·4CH3CN (Ln = La, Pr, Nd, Sm, Gd, Tb, Ho 1-7) (OPPh3 = Triphenylphosphine oxide, {PW12} = phosphotungstic acid). The precise structures are confirmed by X-ray single crystal diffraction and the result shows all complexes are isostructural. Complexes 1-7 are fully characterized by PXRD, FT-IR, TGA, UV diffuse reflectance spectra and terahertz time-domain spectroscopy (THz-TDS). Complex 3 exhibits the highest photocatalytic degradation efficiency for methylene blue (MB) in this series of complexes. The experimental results showed that the photodegradation efficiency can remain constant at the level of 95% after five consecutive cycles. The photocatalytic reaction kinetics and mechanism of complexes were investigated. Additionally, complexes also exhibit photocatalytic hydrogen evolution activity. THz-TDS was used to characterize the complexes and its raw materials, the characteristic peaks of OPPh3 (broad peak at 1.20 THz) and phosphotungstic acid (sharp peaks at 0.23, 0.32 THz) were obtained.


Asunto(s)
Elementos de la Serie de los Lantanoides , Óxidos , Fosfinas , Espectroscopía Infrarroja por Transformada de Fourier
4.
Environ Res ; 206: 112267, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34756915

RESUMEN

Water pollution, which continuously threatens human health and the sustainable development of society, has become a major concern. Photocatalytic degradation is an effective strategy to remove organic dyes from wastewater. For this strategy, it is crucial to select the appropriate catalyst. Using triphenylphosphine oxide (OPPh3) as the ligand, phosphomolybdic acid as the anion template, three new lanthanide complexes [Ln(OPPh3)4(H2O)3](PMo12O40)∙4C2H5OH (1-3) (Ln = Sm, Gd, Tb) were synthesized. The raw materials for the reaction are cheap and readily available. The convenient synthesis method is environmentally friendly, with high yield (70%-80%). Complexes 1-3 are all seven-coordinated mononuclear structures centered on lanthanide ions, [PMo12O40]3- anions and solvent molecules are not coordinated with metal ions. These mononuclear structures eventually form complicated 3D supramolecular structures through hydrogen bonds, Mo-O … π or C-H … π weak interactions. Complexes 1-3 photocatalytic degradation of MB have high removal rates, as catalysts have enough stability to be reused, and can be used as excellent catalysts for the degradation of dye molecules in sewage. Among them, the removal rate of MB by photodegradation of complex 2 was highest (99.50%). In addition, the effects of different initial concentrations of MB solution and different types of organic dyes on the photocatalysis experiment were investigated. The photocatalytic reaction mechanism of complexes 1-3 was also studied. Due to the similar structures of complexes 1-3, they have almost the same THz absorption spectra with different absorption intensity, which may be attributed to the difference of the number of weak interactions. Therefore, terahertz spectroscopy can be used as a sensitive method to distinguish and determine small differences between lanthanide-organic complexes. This is the first time that this spectrum has been used to characterize lanthanide phosphine oxide complexes modified by [PMo12O40]3-.


Asunto(s)
Elementos de la Serie de los Lantanoides , Fosfinas , Aniones , Humanos , Elementos de la Serie de los Lantanoides/química , Óxidos , Polielectrolitos
5.
Dalton Trans ; 50(37): 13124-13137, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34581367

RESUMEN

Photo-induced variation of magnetism from ligand-based electron transfer has been extensively studied because of its potential applications in magneto-optical memory devices, light-responsive switches, and high-density information storage materials. In this review, we discussed the progress in the photo-induced variation of magnetism in coordination polymers with ligand-to-metal charge transfer (LMCT), ligand-to-ligand charge transfer (LLCT) and internal ligand charge transfer (ILCT), which provides fundamentals for the rational design of multi-functional materials. We also discussed the design and synthetic strategy of such molecule-based materials and gave views on the current challenges and growth trends in this field.

6.
Dalton Trans ; 50(29): 10214-10224, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34232237

RESUMEN

Six Cu(i) complexes, [Cu(2,3-f)(bdppmapy)]BF4 (1), [Cu(2,3-f)(bdppmapy)]ClO4 (2), [Cu(2,3-f)(bdppmapy)]CF3SO3 (3), [Cu(imidazo[4,5-f])(bdppmapy)]BF4 (4), [Cu(imidazo[4,5-f])(bdppmapy)]ClO4 (5), and [Cu(imidazo[4,5-f])(bdppmapy)]CF3SO3·MeOH (6·MeOH) (bdppmapy = N,N-bis[(diphenylphosphino)methyl]-2-pyridinamine, 2,3-f = pyrazine[2,3-f][1,10]-phenanthroline, and imidazo[4,5-f] = 1H-imidazo[4,5-f][1,10]-phenanthroline), have been synthesized to explore the effects of counteranions on their crystal structures, photophysical properties, and terahertz (THz) spectra. Time-dependent density functional theory (TD-DFT) shows that the luminescence performance of these complexes is attributed to the metal-to-ligand charge transfer (MLCT) in combination with ligand-to-ligand charge transfer (LLCT). In complexes 1-3, the characteristic peak at 1.4 THz is mainly related to the C-Hπ interaction formed by the H atom on the 4#/5# position of 2,3-f and the benzene ring from the bdppmapy on the adjacent asymmetric unit. The common C-Hπ interaction enhances the rigidity of the structure and has non-negligible influence on the photoluminescence quantum yields (PLQYs): the stronger the C-Hπ interaction is, the higher the quantum yield (QY) is. In complexes 4-6, similar absorption peaks (1.10-1.30 THz) are mainly related to the C-Hπ interactions, and strong absorption peaks (1.50-1.90 THz) are affected by the typical hydrogen bonds N-HF/O and O-HO. These results show that some weak interactions can be characterized by THz time-domain spectroscopy (THz-TDS). So, the THz spectroscopy method would make it possible to tune some of the weak interactions in complex structures to regulate the luminescence of materials.

7.
Chem Commun (Camb) ; 57(41): 5082-5085, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33890586

RESUMEN

Two polymorphs of Cu[(3,4-bis(diphenylphosphino)thiophene)(bis(pyrazol-1-yl)borohydrate)] (1) were isolated. The blue luminescent crystals have evident mechanochromic luminescent (MCL) properties. Based on photophysical and structural analysis, the pore structure in the blue crystals is considered to be the main reason for the MCL properties.

8.
Dalton Trans ; 49(42): 14941-14950, 2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33079106

RESUMEN

The synthesis of four heteroleptic dinuclear Cu(i) complexes bearing tetraphosphine and diimine ligands was reported. Complexes 1-3 were successfully obtained through microwave synthesis while complex 4 was synthesized through traditionally stirring at room temperature. These complexes are listed as follows: [Cu2(Dpq)2(dppeda)](ClO4)2·1.5CH2Cl2 (1), [Cu2(neo)2(dppeda)](ClO4)2·1.3CH2Cl2·1.7C4H10O (2), [Cu2(batho)2(dppeda)](ClO4)2·C4H10O (3), and [Cu2(batho)2(dpppda)](ClO4)2·3CH2Cl2 (4) {(Dpq = pyrazino[2,3-f][1,10]phenanthroline, batho = 4,7-diphenyl-1,10-phenanthroline, neo = 2,9-dimethyl-1,10-phenanthroline, dppeda = N1,N1,N2,N2-tetrakis[(diphenylphosphino)methyl]-1,2-ethanediamine, and dpppda = N1,N1,N4,N4-tetrakis[(diphenylphosphino)methyl]-1,4-benzenediamine}. Their crystal structures have been elucidated by X-ray crystallography and their photophysical properties have been investigated in detail. Photophysical studies and time domain density functional theory (TD-DFT) calculations show that the luminescence performance of these four complexes is ascribed to metal-to-ligand charge transfer (MLCT) mixed with ligand-to-ligand charge transfer (LLCT), and complex 2 shows green emission at 574 nm with the highest quantum yield of up to 52.80%. In addition, the research of photoluminescence properties under the guidance of terahertz spectroscopy technology leads to the preliminary discovery of a correlation between crystal packing and luminescence. It is found that the terahertz spectrum and absorption peak are strongly interdependent on C-Hπ and ππ interactions, and the external weak interactions have negative effects on the luminescence performance. Herein, we predict that the terahertz spectroscopy analysis establishes a bridge between weak interactions (C-Hπ and ππ interactions) and the photoluminescence properties, and puts forward a problem that should be noticed in designing Cu(i) complexes.

9.
Angew Chem Int Ed Engl ; 59(21): 8210-8217, 2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-31985121

RESUMEN

As a kind of photoluminescent material, CuI complexes have many advantages such as adjustable emission, variable structures, and low cost, attracting attention in many fields. In this work, two novel two-coordinate CuI -N-heterocyclic carbene complexes were synthesized, and they exhibit unique dual emission properties, fluorescence and phosphorescence. The crystal structure, packing mode, and photophysical properties under different conditions were systematically studied, proving the emissive mechanism to be the locally excited state of the carbazole group. Based on this mechanism, ultralong room-temperature phosphorescence (RTP) with a lifetime of 140 ms is achieved by selective deuteration of the carbazole group. These results deepen the understanding of the luminescence mechanism and design strategy for two-coordinate CuI complexes, and prove their potential in applications as ultralong RTP materials.

10.
ACS Appl Mater Interfaces ; 11(3): 3262-3270, 2019 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-30608118

RESUMEN

Two new Cu(I) dimers chelated with thiophene ring-introduced diphosphine ligands [Cu(µ2-I)dppt1]2 and [Cu(µ2-I)dppt2]2 (dppt1 = 3,4-bis(diphenylphosphino)thiophene, dppt2 = 2,3-bis(diphenylphosphino)thiophene) have been prepared and studied in terms of photoluminescence and electroluminescence properties. Both dimers exhibited two independent radiative decay pathways, which are equilibrated thermally at room temperature: one is thermally activated delay fluorescence (TADF) via the first singlet excited state (S1) decay and the other is phosphorescence via the first triplet excited state (T1) decay. The dual emission mechanism for both singlet and triplet harvesting, as well as excellent photoluminescence properties such as bluish-green emission color (487 and 483 nm), short decay times (9.46 and 7.62 µs), and high photoluminescence quantum yields (69% and 86%) of the two Cu(I) dimers, implies their potential to be highly efficient emitter molecules for organic light emitting diode (OLED) applications. As a result, the optimized OLEDs with [Cu(µ2-I)dppt2]2 showed the highest efficiency, exhibiting a current efficiency up to 32.2 cd A-1, a peak brightness of 3.67 × 103 cd m-2, as well as a maximum external quantum efficiency of 14.5%.

11.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): o171, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23424457

RESUMEN

In the title mol-ecule, C(7)H(4)N(2)O(2)S(2), the nitro group is twisted by 5.5 (1)° from the plane of the attached benzene ring. In the crystal, N-H⋯S hydrogen bonds link pairs of mol-ecules into inversion dimers, which are linked by weak C-H⋯O inter-actions into sheets parallel to (101). The crystal packing exhibits short inter-molecular S⋯O contacts of 3.054 (4) Šand π-π inter-actions of 3.588 (5) Šbetween the centroids of the five- and six-membered rings of neighbouring mol-ecules.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1295, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23125611

RESUMEN

In the title compound, [CuI(C(8)H(8)N(2)S)(C(18)H(15)P)(2)]·CH(3)OH, the coordination environment around the Cu(I) atom is distorted tetra-hedral, defined by two P atoms of two triphenyl-phosphane ligands, one S atom of a 5-methyl-1H-benzimidazole-2(3H)-thione ligand and one I atom. The complex mol-ecules and the methanol solvent mol-ecules are connected via N-H⋯O and O-H⋯I hydrogen bonds, forming a chain along [010]. An intra-molecular N-H⋯I hydrogen bond is also observed.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2885, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23125682

RESUMEN

The title two-component mol-ecular crystal, C(10)H(8)N(2)·C(2)H(4)N(4)S, was obtained unexpectedly by reaction of Zn(NO(3))(2)·6H(2)O, NH(4)BF(4) with 3-amino-1,2,4-triazole-5-thione (3-AMT) and 4,4'-bipyridine in water. The dihedral angle between the pyridine rings in the 4,4'-bipyridine molecule is 17.00 (13)°. In the crystal, N-H⋯N and N-H⋯S hydrogen bonds between the components lead to the formation of a three-dimensional network. Furthermore, the structure features face-to-face π-π stacking inter-actions between the 4,4'-bipyridine and triazole rings, with a centroid-centroid distance of 2.976 (2) Å.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): m1222-3, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22969502

RESUMEN

In the title compound, [Zn(C(10)H(8)N(2))(C(12)H(8)N(2))(H(2)O)(2)](NO(3))(2)·0.5C(10)H(8)N(2)·H(2)O, the Zn(II) atom is coordinated in a distorted octa-hedral geometry by two N atoms from two 4,4'-bipyridine (4,4'-bipy) ligands, two N atoms from a chelating 1,10-phenanthroline ligand and two O atoms from two mutually cis water mol-ecules. The 4,4'-bipy ligands bridge the Zn(II) atoms into a chain structure along [100]. The uncoordinated 4,4'-bipy mol-ecule lies on an inversion center. O-H⋯O and O-H⋯N hydrogen bonds connect the cationic chains, the nitrate anions, the uncoordinated 4,4'-bipy mol-ecules and the water mol-ecules into tow-dimensional networks.

15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 8): m1022-3, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22904705

RESUMEN

The title complex, [Ag(2)(C(25)H(22)P(2))(2)(C(9)H(7)N)(2)](CF(3)SO(3))(2)·C(9)H(7)N, was prepared by the reaction of silver(I) trifluoro-methane-sulfonate with isoquinoline and bis-(diphenyl-phosphan-yl)methane (dppm). The dinuclear mol-ecule is located about a center of inversion and the Ag(I) atom is coordinated by two dppm P atoms and one isoquinoline N atom, forming an eight-membered metalla ring. In addition, in the asymmetric unit, there is a half-mol-ecule of isoquinoline located about a center of inversion. Since this mol-ecule does not possess this symmetry, for one position in the ring there is superposition of both a C atom of a C-H group and the isoquinoline N atom. In the structure, the Ag-P distances [2.4296 (9) and 2.4368 (9) Å] agree with the corresponding distances in related structures, while the Ag-N bond length [2.489 (3) Å] is slightly longer than that in related structures. On the other hand, the P-Ag-P angle [156.44 (3)°] is much larger than the corresponding angles in related structures. The trifluoro-methane-sulfonate anions do not coordinate to Ag(I) atoms. As is usually found for these anions, the -CF(3) group is disordered over two orientations [occupancies = 0.57 (12) and 0.43 (12)].

16.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): m706, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22590183

RESUMEN

The title complex, [Ag(C(18)H(15)P)(4)]BF(4), was prepared by the reaction of silver(I) tetra-fluorido-borate and triphenyl-phosphane in the presence of 1,2-bis-(pyridin-2-yl)ethyl-ene. The Ag(I) atom is tetra-hedrally coordinated by four P atoms from triphenyl-phosphane (PPh(3)) ligands. Due to symmetry, the tetra-fluorido-borate anion is disordered over three positions (each with one third occupancy). The tetra-fluorido-borate anion does not coordinate to the Ag(I) atom.

17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): m283-4, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22412430

RESUMEN

In the title coordination compound, [Cu(NCS)(C(9)H(7)N)(C(18)H(15)P)](n), the Cu(I) atom is tetra-hedrally coordinated by one N atom from an isoquinoline ligand, one P atom from a triphenyl-phospane ligand, and one N and one S atom from two thio-cyanate anions. The thio-cyanide anions bridge the Cu(I) atoms into a chain along [100]. π-π inter-actions between the pyridine and benzene rings of the isoquinoline ligands connect the chains [centroid-to-centroid distance = 3.722 (3) Å].

18.
Artículo en Inglés | MEDLINE | ID: mdl-22259542

RESUMEN

In the crystal structure of the title compound, C(5)H(8)N(4), adjacent mol-ecules are connected through N-H⋯N hydrogen bonds, resulting in a zigzag chain along [100]. The amino groups and heterocyclic N atoms are involved in further N-H⋯N hydrogen bonds, forming R(2) (2)(8) motifs.

19.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 12): o3450, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23476263

RESUMEN

In the title salt, C10H10N2(2+)·2C7H4NS2(-), the complete 4,4'-bipyridine-1,1'-diium dication is generated by a center of symmetry. In the crystal, N-H⋯N hydrogen bonds are observed between the cations and anions.

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): m1367, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23284347

RESUMEN

The title complex, [Ag(2)(NO(2))(2)(C(25)H(22)P(2))(2)]·2CH(3)CN, is a centrosymmetric dimer in which two bis(diphenylphosphino)methane ligands bridge two Ag(+) ions, forming an eight-membered ring with a short Ag⋯Ag separation of 3.1809 (5) Å. The distorted P(2)O(2) coordination of the cation is completed by two O-donors from a symmetric bidentate chelate NO(2) (-) anion [Ag-O = 2.550 (3) and 2.567 (3) Å].

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