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1.
Ecotoxicol Environ Saf ; 277: 116350, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38653026

RESUMO

Inorganic arsenic is a well-established environmental toxicant linked to acute liver injury, fibrosis, and cancer. While oxidative stress, pyroptosis, and ferroptosis are known contributors, the role of PTEN-induced kinase 1 (PINK1)-mediated mitophagy in arsenic-induced hepatic immunotoxicity remains underexplored. Our study revealed that acute arsenic exposure prompts differentiation of hepatic dendritic cells (DCs) and T helper (Th) 1, Th2, Th17, and regulatory T (Treg) cells, alongside increased transcription factors and cytokines. Inorganic arsenic triggered liver redox imbalance, leading to elevated alanine transaminase (ALT), hydrogen peroxide (H2O2), malondialdehyde (MDA), and activation of nuclear factor erythroid 2-related factor (Nrf2)/heme oxygenase-1 (HO-1) pathway. PINK1-mediated mitophagy was initiated, and its inhibition exacerbates H2O2 accumulation while promoting DCs/Th1/Th2/Treg differentiation in the liver of arsenic-exposed mice. Mitoquinone (MitoQ) pretreatment relieved arsenic-induced acute liver injury and immune imbalance by activating Nrf2/HO-1 and PINK1-mediated mitophagy. To our knowledge, this is the first report identifying PINK1-mediated mitophagy as a protective factor against inorganic arsenic-induced hepatic DCs/Th1/Th2 differentiation. This study has provided new insights on the immunotoxicity of inorganic arsenic and established a foundation for exploring preventive and therapeutic strategies targeting PINK1-mediated mitophagy in acute liver injury. Consequently, the application of mitochondrial antioxidant MitoQ may offer a promising treatment for the metalloid-induced acute liver injury.


Assuntos
Antioxidantes , Arsênio , Diferenciação Celular , Fígado , Mitofagia , Compostos Organofosforados , Proteínas Quinases , Animais , Mitofagia/efeitos dos fármacos , Camundongos , Fígado/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Proteínas Quinases/metabolismo , Diferenciação Celular/efeitos dos fármacos , Compostos Organofosforados/toxicidade , Compostos Organofosforados/farmacologia , Arsênio/toxicidade , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Células Dendríticas/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Masculino , Linfócitos T Reguladores/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos
2.
J Org Chem ; 86(23): 16707-16715, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34747181

RESUMO

The development of small organic CPL-active molecules with large luminescent dissymmetry factors is highly demanded due to their promising applications in chiroptical devices and sensors. This work describes the design and synthesis of a new family of CPL-active BF2 complexes, (Rp)/(Sp)-3a-3e, which were constructed by fusing a N̂O-chelated BF2 complex with [2.2]paracyclophane. These complexes display aggregation-amplified CPL with moderate dissymmetry factors values and moderate quantum yields both in solution and in the solid state. In addition, these photophysical properties were rationalized via X-ray diffraction and TD-DFT calculations.

3.
Angew Chem Int Ed Engl ; 59(9): 3455-3459, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31808988

RESUMO

The synthesis of hierarchical nanosized zeolite materials without growth modifiers and mesoporogens remains a substantial challenge. Herein, we report a general synthetic approach to produce hierarchical nanosized single-crystal aluminophosphate molecular sieves by preparing highly homogeneous and concentrated precursors and heating at elevated temperatures. Accordingly, aluminophosphate zeotypes of LTA (8-rings), AEL (10-rings), AFI (12-rings), and -CLO (20-rings) topologies, ranging from small to extra-large pores, were synthesized. These materials show exceptional properties, including small crystallites (30-150 nm), good monodispersity, abundant mesopores, and excellent thermal stability. A time-dependent study revealed a non-classical crystallization pathway by particle attachment. This work opens a new avenue for the development of hierarchical nanosized zeolite materials and understanding their crystallization mechanism.

4.
J Biol Inorg Chem ; 24(7): 1077-1085, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31515622

RESUMO

Hydrogen polysulfides (H2Sn, n > 1), as the oxidized forms of H2S, have attracted increasing attention these years due to their involvement in signaling transduction and cytoprotective processes. It is necessary to detect H2Sn in living systems for the study of their functions. In this work, we report a BODIPY-based near-infrared emitting fluorescence probe NIR-PHS1, with "turn-on" response, rapid response rate (within 10 min), outstanding selectivity and excellent sensitivity (detection limit = 12 nM) response towards H2Sn. The probe was successfully applied to the visualizing of endogenous H2Sn in living cells. Moreover, it can be used for near-infrared in vivo imaging of H2Sn in living mice. Therefore, NIR-PHS1 could be a potential imaging tool to study the biological roles of H2Sn in living systems.


Assuntos
Corantes Fluorescentes/química , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/metabolismo , Raios Infravermelhos , Imagem Óptica/métodos , Animais , Compostos de Boro/química , Sobrevivência Celular , Células HeLa , Humanos , Camundongos
5.
Org Biomol Chem ; 16(27): 4977-4984, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29767197

RESUMO

A new family of aggregation-induced emission (AIE)-active monoboron and bisboron complexes based on benzothiazole-hydrazone chelates was synthesized. These complexes showed very weak fluorescence in fluid solution due to active intramolecular rotation and were emissive in high-viscosity solvents or in the aggregation state. Single crystal X-ray diffraction analyses and theoretical calculations were carried out to explain AIE behavior. The large Stokes shifts (3590-7400 cm-1) and relatively highly efficient solid-state emission make these complexes valuable AIE luminophores for further potential applications.

6.
Org Biomol Chem ; 13(20): 5775-82, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25906250

RESUMO

Two pyridine-ketoiminate-based organoboron complexes (2 and 3) were developed. 2 and 3 showed very weak emission in low-viscosity organic solvents because of the intramolecular rotation induced non-radiative process. Their emission can be dramatically enhanced by the increase in solvent viscosity or by molecular aggregation in the solid state. Moreover, 2 and 3 exhibited intense emission with high quantum yield of 0.53 and 0.46, respectively. X-ray crystallographic analysis showed that the weak intermolecular interactions such as C-H···F and C-H···π by fixing the molecular conformations of 2 and 3 were responsible for intense luminescence in the solid state. The large Stokes shifts and high efficient solid-state emission of 2 and 3 make them valuable AIE luminophores for further potential applications in the fields of fluorescence imaging and materials science.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Iminas/química , Luminescência , Piridinas/química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Solventes/química , Viscosidade
7.
Int Urol Nephrol ; 56(1): 191-198, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37195572

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is an important cause of morbidity and mortality in peritoneal dialysis (PD) patients. Cardiovascular calcification (CVC) is highly prevalent in PD patients and could predict their cardiovascular mortality. Soluble urokinase plasminogen activator receptor (suPAR) is closely associated with coronary artery calcification in hemodialysis patients and is an important predictor of CVD. However, the role of suPAR in PD patients is poorly understood. We investigated the relationship between serum suPAR and CVC in PD patients. METHODS: Abdominal aortic calcification (AAC) was assessed by lateral lumbar radiography, coronary artery calcification (CAC) by multi-slice computed tomography, and cardiac valvular calcification (ValvC) by echocardiography. CVC was defined as confirmed presence of calcification in one site (AAC, CAC, or ValvC). Patients were divided into CVC group and non-CVC group. Demographic characteristics, biochemical variables, comorbidities, PD regimen, serum suPAR, and medication were compared between the two groups. Logistic regression was conducted to determine association between serum suPAR and presence of CVC. The receiver-operator curve (ROC) was plotted to calculate the area under the curve (AUC) for suPAR to identify CVC and ValvC. RESULTS: Of 226 PD patients, 111 (49.1%) had AAC, 155 (68.6%) had CAC, and 26 (11.5%) had ValvC. There were significant differences in age, BMI, diabetes, white blood cell, phosphorus, hs-CRP, suPAR, time on dialysis, total volume of dialysate, ultrafiltration, volume of urine, and Kt/V between CVC and non-CVC group. Serum suPAR was associated with CVC by multivariate logistic regression analysis in PD patients, especially in elderly patients. The levels of serum suPAR were closely related to the degree of AAC, CAC, and ValvC in PD patients. The incidence of CVC was higher in patients with higher levels of suPAR. The ROC curve showed that serum suPAR had a predictive value for CVC (AUC = 0.651), especially for ValvC (AUC = 0.828). CONCLUSION: Cardiovascular calcification is prevalent in PD patients. High levels of serum suPAR are associated with cardiovascular calcification in PD patients, especially in elderly patients.


Assuntos
Calcinose , Doenças Cardiovasculares , Doença da Artéria Coronariana , Diálise Peritoneal , Humanos , Biomarcadores , Doença da Artéria Coronariana/epidemiologia , Diálise Peritoneal/efeitos adversos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Fatores de Risco
8.
Acta Crystallogr C ; 69(Pt 6): 588-93, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23744373

RESUMO

Two polyoxometallate-based compounds, tris[1,1'-(butane-1,4-diyl)bis(1H-imidazol-3-ium)] bis[tetracosa-µ2-oxido-dodecaoxido-µ12-phosphato-dodecamolybdenum(VI)], (C10H16N4)3[PMo12O40]2, (I), and 1,1'-(butane-1,4-diyl)bis(1H-imidazol-3-ium) 1-[4-(1H-imidazol-1-yl)butyl]-1H-imidazol-3-ium tetracosa-µ2-oxido-dodecaoxido-µ12-phosphato-dodecamolybdenum(VI) dihydrate, (C10H16N4)(C10H15N4)[PMo12O40]·2H2O, (II), were synthesized by hydrothermal techniques at different pH values. The stoichiometric ratio between the polyoxometallate (POM) anions and organic cations is 2:3 in (I), with one of the cations lying on an inversion centre. The doubly protonated 1,1'-(butane-1,4-diyl)diimidazole (BIM) cations are linked to the [PMo12O40](3-) anions by hydrogen bonds to form a three-dimensional supramolecular network. The stoichiometric ratio of POM anions and organic cations is 1:2 in (II), and the anion is located about a centre of inversion. The partly protonated BIM cations and solvent water molecules form hydrogen bonds with the [PMo12O40](3-) anions, yielding a two-dimensional supramolecular layer. The different lattice architectures of (I) and (II) may be governed by the ratio between the POM anions and organic cations, which, in turn, is determined by the pH value.

9.
Int Urol Nephrol ; 55(5): 1271-1278, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36454448

RESUMO

BACKGROUND: Cardiovascular events (CVE) are the leading cause of death in peritoneal dialysis (PD) patients. The predictive value of cardiac valve calcification (CVC) for CVE in dialysis patients remains controversial. In particular, such studies are limited in PD patients. We aimed to examine the predictive role of CVC for CVE and cardiovascular mortality in PD patients. METHODS: A retrospective analysis was performed on patients who initiated PD in our hospital. According to the result of echocardiography, patients were divided into CVC group and non-CVC group. The differences in baseline demographic characteristics, biochemical variables, comorbidities, and clinical outcomes between the two groups were compared. Kaplan-Meier method was used to obtain survival curves. The Cox regression model was used to evaluate the influence of CVC for cardiovascular outcomes. The inverse probability of treatment weighting (IPTW) was used to eliminate influence of the confounders in the groups. RESULTS: 458 peritoneal dialysis patients were enrolled in this study. 77 patients were in CVC group and 381 patients in non-CVC group. The average follow-up time was (32 ± 21) months. At baseline, the absolute standardized difference (ASD) of age, BMI, history of CVE, diabetes, LVEF, LVMI, albumin, calcium, phosphorus, triglycerides, hsCRP, urine volume, Kt/V, statins and vitamin D intake rate were greater than 0.1 between the two groups. All of ASD dropped to less than 0.1 after IPTW, which meant that the balance had been reached between the two groups. Multivariable logistic analysis showed that advanced age, diabetes, and hyperphosphatemia were associated with CVC. The Kaplan-Meier survival curve showed the cumulative CVE-free survival rate and cardiovascular survival rate of CVC group were significantly lower than that of non-CVC group before and after IPTW (log-rank P < 0.05). After IPTW was used to eliminate the effect of confounders, multivariate Cox regression analysis still showed CVC was an independent risk factor for CVE (HR = 2.383, 95% CI 1.331~4.264, P = 0.003) and cardiovascular mortality (HR = 2.347, 95% CI 1.211~4.548, P = 0.012) in PD patients. CONCLUSION: The prevalence of CVC is high in peritoneal dialysis patients. CVC is an independent risk factor for CVE and cardiovascular mortality in peritoneal dialysis patients.


Assuntos
Doenças Cardiovasculares , Doenças das Valvas Cardíacas , Diálise Peritoneal , Humanos , Estudos Retrospectivos , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/epidemiologia , Diálise Peritoneal/efeitos adversos , Diálise Peritoneal/métodos , Probabilidade , Valvas Cardíacas , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
10.
J Surg Res ; 175(1): 123-30, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21492877

RESUMO

BACKGROUND: Transplant arteriosclerosis is a hallmark of chronic rejection and is still the major limiting factor affecting the success of long-term organ transplants. Development of transplant arteriosclerosis is refractory to conventional immunosuppressive drugs, and adequate therapy is not yet available. The aim of this study was to determine the role of Cordyceps sinensis extracts in reducing the formation of transplant arteriosclerosis in a rat aortic transplant model. METHODS: Lewis rat aortic allografts were transplanted into Brown-Norway recipient rats. Recipients received 0.5, 1, 2, and 5 mg/kg of Cordyceps sinensis extracts (or control saline) daily via intragastric injection for 60 d. Grafts were harvested 60 d post-transplantation and intimal thickness determined microscopically following hematoxylin and eosin (H and E) staining and abdominal aorta protein profiles determined by Western blot analysis. Cellular localization was assessed by histology and immunohistochemistry and the serum analyzed for tumor necrosis factor alpha (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) by enzyme-linked immunosorbent assay (ELISA). RESULTS: C. sinensis administration resulted in a significant reduction in neointimal formation (neointimal thickness 8.27 ± 1.95 µm [0.5 mg/kg], 3.69 ± 1.43 µm [1 mg/kg], 3.69 ± 1.43 µm [1 mg/kg], 3.69 ± 1.43 µm [1 mg/kg] versus 11.42 ± 2.67 µm [control]) and in the proliferative activity of vascular smooth muscle cells. In addition, localized expression of TNF-α and ICAM-1 in transplant aortas was characterized by immunohistochemistry and immunoblot analyses demonstrating that C. sinensis treatment significantly reduced TNF-α and ICAM-1 levels compared with levels observed in controls (P < 0.05). Serum TNF-α and ICAM-1 levels were significantly reduced in C. sinensis-treated animals compared with controls (P < 0.05). CONCLUSION: C. sinensis treatment effectively reduced the formation of transplant arteriosclerosis in a rat aortic transplant model.


Assuntos
Aorta Abdominal/transplante , Arteriosclerose/tratamento farmacológico , Cordyceps , Inflamação/tratamento farmacológico , Túnica Íntima/efeitos dos fármacos , Animais , Misturas Complexas/farmacologia , Misturas Complexas/uso terapêutico , Masculino , Ratos , Transplante Homólogo
11.
Chem Commun (Camb) ; 58(100): 13955-13958, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36448567

RESUMO

AIE-active phenyl- and [2.2]paracyclophanyl-based aurones (2-Ph and 2-PCP) were synthesized and investigated with different structures and photophysical properties. The results illustrated that the PCP ring can provide chirality, electron-donating ability and steric hindrance. Accordingly, (Rp)/(Sp)-2-PCP exhibit high sensitivity in trace water detection and aggregation-induced CPL with enhanced quantum yields and luminescence dissymmetry factors.


Assuntos
Benzofuranos , Luminescência , Água , Elétrons
12.
Dalton Trans ; 51(8): 3248-3253, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35132984

RESUMO

The construction of cluster-based crystalline chalcogenide structures through the traditional solvothermal method relies on synergistic control of precursors, template cations and auxiliary solvents. Generally, the combination of metal precursors plays a crucial role in controlling the size of clusters, while organic templates and auxiliary solvents usually contribute to the type of clusters and architecture of the framework. Decades of synthetic efforts have been mainly devoted to expanding organic amine templates for constructing new structures. However, the important role of auxiliary solvents in enriching the chalcogenide family is usually disregarded. Reported here are several new crystalline In-Se compounds (ISP-1 to 4) with different dimensions, obtained by elaborately regulating auxiliary solvents under the direction of the same organic template, piperidine. Of these four structures, ISP-1 is constructed by irregular supertetrahedral clusters, giving a novel 2D structure with a corner-shared single Se atom and In2Se3 five-member ring as linkers; ISP-2 has a 1D structure composed by interlinked In2Se3 five-member rings; ISP-4 is constructed by supertetrahedral T2 clusters exhibiting an uncommon zeolite-like mog network.

13.
Dalton Trans ; 50(37): 12963-12969, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581357

RESUMO

Planar chiral [2.2]paracyclophanyl-based boron fluoride complexes (3a-3d) were designed and facilely synthesized. The X-ray structure study, theoretical calculations and CD spectra reveal the intense emission and planar chiral structures of these complexes. In particular, 3a-3d show moderate quantum yields and large Stokes shifts both in solution and solid state. Furthermore, the blue-shifted mechanochromic properties of 3a and 3b were both investigated in the solid state. This work is the first study on planar chiral boron monofluoride complexes within the boron fluoride complex field.

14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): m122, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21522533

RESUMO

The title compound, {(C(6)H(16)N)[Sn(C(6)H(5))(3)(C(23)H(14)O(6))]}(n), has an infinite chain structure, formed through monodentate carboxyl-ate groups of the pamoic acid anion. The anion bridges two symmetry-related Sn(IV) ions and the resulting polymeric chains are parallel to [201] in the crystal. Et(3)NH(+) cations are inserted between the chains. The coordination of the Sn(IV) atom is completed by three phenyl ligands, giving a distorted trigonal-bipyramidal geometry.

15.
Dalton Trans ; 49(31): 10970-10976, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32725036

RESUMO

A synthetic pathway for the directed preparation of three novel polyoxovanadate-based copper frameworks (POVCFs), i.e., [Cu0.5(1-ipIM)2]2[V4O11] (POVCF 1), [Cu(1-ipIM)2](VO3)2 (POVCF 2) and [Cu(1-pIM)4](HpIM)4[V10O28] (POVCF 3) (1-ipIM = 1-isopropylimidazole; 1-pIM = 1-propylimidazole) using bifunctional imidazole molecules as organic ligands and base has been developed. Systematic studies revealed that the variable base enviroment in the reaction is the key step in the preparation of 1D to 3D supermolecular networks of POVCFs 1-3. Single crystal X-ray diffraction analyses demonstrated that the Cu2+ atoms of POVCFs 1-2 were coordinated with four imidazole derivative molecules and two different polyoxovanadate {[V4O11]2- and [V10O28]6-} clusters, respectively, exhibiting a [CuN4O2] binding set and a distorted octahedral geometry. Specifically, POVCF 1 exhibited adjacent [V4O11]2- that dangle up and down arranged in a parallel 2D network and further coordinated with [Cu(1-ipIM)4]2+ to form a 3D supramolecular structure. However, POVCF 3 presented one tetrahedral coordinated vanadium atom and one four-coordinated copper atom and they further gave rise to a 1D network by the Cu-O and V-O bonds. More importantly, these POVCFs were further studied in the construction of C-N bond reactions of primary amines under mild conditions, and it was found that POVCF 1 displayed efficient heterogeneous catalytic activities in the Chan-Lam reaction (yields up to 89%).

16.
Dalton Trans ; 49(40): 13993-13998, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33078802

RESUMO

One bonded- and one discreted-Lindqvist hexatungstate-based copper hybrids (Cu-POMs) ([Cu2(O)OH(phen)2]2[W6O19]·6H2O (1) and [Cu2(phen)4Cl] [HW6O19]·2H2O (2) (phen = 1,10-phenanthroline)) were controllably synthesized and routinely characterized. Cu-POMs 1-2 consisted of identical [W6O19] unit and similar copper-phen complexes, the two units are bonded via four Cu-O chemical bonds in compound 1; however, compound 2 is discreted and stabilized by intermolecular electrostatic interactions. Importantly, these Cu-POMs catalysts were first applied in the novel reaction for the preparation of 2-phenylquinoxalines via the one-pot coupling and oxidation reactions of 2-haloanilines with vinyl azides or 3-phenyl-2H-azirines under mild conditions, and Cu-POMs 1 showed higher catalytic performance in good yields (79-84%). The reactions exhibit some functional group tolerance and allow for the preparation of a number of 2-phenylquinoxalines.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117295, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31254752

RESUMO

Hydrogen polysulfides (H2Sn, n > 1) have attracted increasing attention in biological systems due to its redox signaling effect. To illustrate the process of the physiological and pathological roles played by H2Sn, accurate detection is highly desired. In this work, we report a BODIPY-based fluorescent probe (BDP-PHS) for ratiometric H2Sn sensing. BDP-PHS shows higher sensitivity and selectivity ratiometric response toward H2Sn than various biological related species. Moreover, BDP-PHS has been successfully applied in imaging of H2Sn in living cells.


Assuntos
Técnicas Biossensoriais/métodos , Compostos de Boro/química , Hidrogênio/análise , Imagem Molecular , Sondas Moleculares/química , Sulfetos/análise , Compostos de Boro/síntese química , Sobrevivência Celular , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Fatores de Tempo
18.
RSC Adv ; 9(55): 32219-32225, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-35530811

RESUMO

By combining the fluorophores of axially chiral 1,1'-binaphthol (BINOL) and 1,4-dihydropyridine derivatives, axially chiral 1,4-dihydropyridine derivatives ((R)-/(S)-2) with aggregation-induced emission (AIE) in exciplexes were designed and synthesized. (R)-/(S)-2 emitted low fluorescence in THF solutions of their locally excited states; however, they emitted red-shifted fluorescence in the aggregate state upon exciplex formation. Moreover, (R)-/(S)-2 showed linear and multi-exponential relationships between their local excited and exciplex fluorescence intensities and the viscosity of the medium, which allowed us to determine the viscosities of different mixed solvents. In addition, as an axially chiral viscosity probe, (R)-/(S)-2 show excellent CD signals and have potential applications in the fields of chiral recognition and fluorescence imaging, which will broaden the new family of AIE fluorophores. To the best of our knowledge, there are few reports of axially chiral intramolecular exciplex-mediated AIE molecules.

19.
Dalton Trans ; 47(42): 15002-15008, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30302444

RESUMO

Propeller-shaped pyridyl-enolato-catecholate/-salicyl spiroborates (Sborepy1-6) were synthesized. The complexes Sborepy3-6 show weak emission in fluid solution and aggregation-induced emission enhancement in the aggregation state with large Stokes shifts of 4025-5237 cm-1. Moreover, intense solid-state emissions with high Φf ranging from 25% to 37% were observed for Sborepy3-6 owing to the weak intermolecular interactions in their solid-state. The AIE and intense solid-state emission have been revealed via the X-ray diffraction analysis and theoretical calculations. Furthermore, the solvatochromism in the solution state and the potential application as a fluorescent acidic vapour sensor in the solid state of Sborepy3 and Sborepy6 were also demonstrated.

20.
RSC Adv ; 8(46): 26180-26187, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35541935

RESUMO

A heteropoly acid based organic hybrid heterogeneous catalyst, HMQ-STW, was prepared by combining 8-hydroxy-2-methylquinoline (HMQ) with Keggin-structured H4SiW12O40 (STW). The catalyst was characterized via elemental analysis, X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and potentiometric titration analysis. The catalytic performance of the catalyst was assessed in the ketalization of ketones with glycol or 1,2-propylene glycol. Various reaction parameters, such as the glycol to cyclohexanone molar ratio, catalyst dosage, reaction temperature and time, were systematically examined. HMQ-STW exhibited a relatively high yield of corresponding ketal, with 100% selectivity under the optimized reaction conditions. Moreover, catalytic recycling tests demonstrated that the heterogeneous catalyst exhibited high potential for reusability, and it was revealed that the organic modifier HMQ plays an important role in the formation of a heterogeneous system and the improvement of structural stability. These results indicated that the HMQ-STW catalyst is a promising new type of heterogeneous acid catalyst for the ketalization of ketones.

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