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1.
Aging (Albany NY) ; 132021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33589572

RESUMO

Non-small cell lung cancer (NSCLC) is the most common tumor affecting modern people and is associated with severe morbidity and high mortality. Exosomal long non-coding RNAs as crucial regulators are involved in cancer progression. However, the role of exosomal lncRNA LINC00662 in the development of NSCLC remains unclear. Here, we aimed to explore the impact of exosomal lncRNA LINC00662 on the NSCLC progression and the underlying mechanism. Significantly, we revealed that the expression of lncRNA LINC00662 was elevated in the plasma exosome of NSCLC patients. Exosomal LINC00662 promoted proliferation, invasion, and migration, and inhibited apoptosis and cell cycle arrest of NSCLC cells. Mechanically, LINC00662 was able to serve as a miR-320d sponge in NSCLC cells. MiR-320d could target E2F1 in NSCLC cells. Exosomal LINC00662 contributed to the progression of NSCLC by miR-320d/E2F1 axis in vitro. Remarkably, exosomal LINC00662 enhanced the tumor growth of NSCLC in vivo. Thus, we conclude that exosomal lncRNA LINC00662 promotes NSCLC progression by modulating miR-320d/E2F1 axis. Our finding provides new insights into the mechanism by which exosomal lncRNA LINC00662 contributes to the development of NSCLC. LncRNA LINC00662, miR-320d, and E2F1 may serve as potential targets for NSCLC therapy.

2.
J Agric Food Chem ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33529031

RESUMO

Oilseeds are an important source of dietary lipids, and a comprehensive analysis of oilseed lipids is of great significance to human health, while information about the global lipidomes in oilseeds was limited. Herein, an ultrahigh-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry method for comprehensive lipidomic profiling of oilseeds was established and applied. First, the lipid extraction efficiency and lipid coverage of four different lipid extraction methods were compared. The optimized methyl tert-butyl ether extraction method was superior to isopropanol, Bligh-Dyer, and Folch extraction methods, in terms of the operation simplicity, lipid coverage, and number of identified lipids. Then, global lipidomic analysis of soybean, sesame, peanut, and rapeseed was conducted. A total of 764 lipid molecules, including 260 triacylglycerols, 54 diacylglycerols, 313 glycerophospholipids, 36 saccharolipids, 35 ceramides, 30 free fatty acids, 21 fatty esters, and 15 sphingomyelins were identified and quantified. The compositions and contents of lipids significantly varied among different oilseeds. Our results provided a theoretical basis for the selection and breeding of varieties of oilseed as well as deep processing of oilseed for the edible oil industry.

3.
BMC Nephrol ; 22(1): 11, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413146

RESUMO

BACKGROUND: AarF domain-containing kinase 4 (ADCK4)-associated glomerulopathy is a mitochondrial nephropathy caused by mutations in the ADCK4 gene, which disrupt coenzyme Q10 biosynthesis. CASE PRESENTATION: We report the case of a 25-year-old female patient with ADCK4-associated glomerulopathy presenting with proteinuria (and with no additional systemic symptoms). A known missense substitution c.737G > A (p.S246N) and a novel frameshift c.577-600del (p.193-200del) mutation were found. We followed the patient for 24 months during supplementation with coenzyme Q10 (20 mg/kg/d - 30 mg/kg/d) and describe the clinical course. In addition, we measured serum and urine coenzyme Q10 levels before and after coenzyme Q10 supplementation and compared them with those of healthy control subjects. The patient's urinary coenzyme Q10 to creatinine ratio was higher than that of healthy controls before coenzyme Q10 supplementation, but decreased consistently with proteinuria after coenzyme Q10 supplementation. CONCLUSIONS: Although the use of urinary coenzyme Q10 as a diagnostic biomarker and predictor of clinical remission in patients with ADCK4-associated glomerulopathy should be confirmed by larger studies, we recommend measuring urinary coenzyme Q10 in patients with isolated proteinuria of unknown cause, since it may provide a diagnostic clue to mitochondrial nephropathy.

4.
J Agric Food Chem ; 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33427466

RESUMO

Flax lignans (SDG) and sinapic acid (SA) both have the function of antioxidation and anti-inflammation. However, previous studies have focused mainly on biochemical measurements, gene expression analysis, and clinical assessments. There are limited studies that systematically reveal the underlying mechanism of the anti-inflammation effect of SDG or SA from the lipidomic point of view. Herein, the integrated lipidomic profiling platform was used for the analysis of free fatty acids (FFAs), phospholipids (PLs), triacylglycerols (TAGs), and oxylipins in high-fat (HF)-diet-fed mice after SDG or SA administration. Dietary supplementation of SDG or SA downregulated the levels of total TAGs and FFAs in the ApoE-/- mice model. Furthermore, 28 potential lipids were screened out and considered as key evaluation factors to understand the anti-inflammation function and mechanism of SDG and SA. The results indicated that the anti-inflammatory effect of SDG and SA was principally exerted via regulation of lipid homeostasis.

5.
J Am Heart Assoc ; 10(3): e018248, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33506695

RESUMO

Background Noncontrast computed tomography (NCCT) markers are the emerging predictors of hematoma expansion in intracerebral hemorrhage. However, the relationship between NCCT markers and the dynamic change of hematoma in parenchymal tissues and the ventricular system remains unclear. Methods and Results We included 314 consecutive patients with intracerebral hemorrhage admitted to our hospital from July 2011 to May 2017. The intracerebral hemorrhage volumes and intraventricular hemorrhage (IVH) volumes were measured using a semiautomated, computer-assisted technique. Revised hematoma expansion (RHE) was defined by incorporating the original definition of hematoma expansion into IVH growth. Receiver operating characteristic curve analysis was used to compare the performance of the NCCT markers in predicting the IVH growth and RHE. Of 314 patients in our study, 61 (19.4%) had IVH growth and 93 (23.9%) had RHE. After adjustment for potential confounding variables, blend sign, black hole sign, island sign, and expansion-prone hematoma could independently predict IVH growth and RHE in the multivariate logistic regression analysis. Expansion-prone hematoma had a higher predictive performance of RHE than any single marker. The diagnostic accuracy of RHE in predicting poor prognosis was significantly higher than that of hematoma expansion. Conclusions The NCCT markers are independently associated with IVH growth and RHE. Furthermore, the expansion-prone hematoma has a higher predictive accuracy for prediction of RHE and poor outcome than any single NCCT marker. These findings may assist in risk stratification of NCCT signs for predicting active bleeding.

6.
J Hazard Mater ; 403: 124058, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265061

RESUMO

Dissolution of the exposed sphalerite (marmatite) in abandoned mining sites and tailings may exacerbate acid and metalliferous drainage (AMD) hazards. Cupric ions are inevitable ions in AMD systems but its action mechanism on the dissolution of sphalerite is still unclear. In this work, the possible phase transition from sphalerite to chalcopyrite is firstly discovered in acidic cupric ions solution according to the results of Raman and (synchrotron radiation-based) X-ray (micro-) diffractometer spectra, which should be an important reason that mediates the dissolution of sphalerite. Results of DFT calculations reveal the underlying mechanism that Cu2+ can selectively replace zinc in marmatite lattices and further diffuse into the matrix. Additionally, a strong correlation between the cupric ion consumption with the pH value variation is discussed and the effects of the formed new phase on the dissolution kinetics of marmatite were researched. According to this work, the action mechanism of cupric ions on sphalerite dissolution in acidic environments is furtherly clarified.

7.
J Environ Manage ; 278(Pt 2): 111533, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33157466

RESUMO

Iron plaque is the amorphous and/or crystalline layer of Fe and Mn (hydr)oxides formed on the root surface of wetland plants. It could adsorb and co-precipitate metal(loid)s at the rhizosphere, thus modulating the uptake and accumulation of metal elements in plants. In this study, the Fe(II)/Mn(II)-oxidizing bacteria Burkholderia sp. D416 (D416) and Pseudomonas sp. YGL (YGL) were isolated from Cd-contaminated rice field, both hydroponic experiment and pot experiment were performed to assess the impact of bacterial inoculation on iron plaque formation, elemental content of the plaque, plant dry mass, antioxidant enzyme activity and Cd content in rice plants. The results revealed that inoculation with D416, YGL, and D416+YGL stimulated iron plaque formation on the root surface of the hydroponic rice. The content of C, N, O, Na, Mg, Al, Si, P, S, Cl, K, Fe and Ca in the root plaque were affected by the bacterial inoculation and varied among different plant growth stages. The pot experiment indicated that inoculation with D416 increased the root dry biomass by 58.89%, and the combined inoculation of D416 and YGL increased the dry biomass of root, shoot and grain by 16.89%, 21.66% and 23.26%, respectively. Importantly, YGL inoculation decreased the Cd translocation from root to shoot and from glume to brown rice grain by 50.00% and 50.27%, respectively, and the Cd content in shoot and brown rice grain were decreased by 20.00% and 34.48%, respectively. Taken together, the elemental content of the iron plaque and Cd content in rice plants varied among different plant growth stages and when plants were inoculated with different bacterial strains. YGL dramatically reduced the Cd content in brown rice grain, thus it could potentially be used to reduce Cd content in rice crop grown in Cd-contaminated soils.


Assuntos
Oryza , Poluentes do Solo , Bactérias , Cádmio/análise , Ferro , Manganês , Oxirredução , Raízes de Plantas/química , Rizosfera , Solo , Poluentes do Solo/análise
8.
Int Immunopharmacol ; 91: 107262, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338863

RESUMO

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic has spread globally. Therapeutic options including antivirals, anti-inflammatory compounds, and vaccines are still under study. Convalescent plasma(CP) immunotherapy was an effective method for fighting against similar viral infections such as SARS-CoV, and MERS-CoV. In the epidemic of COVID-19, a large number of literatures reported the application of CP. However, there is controversy over the efficacy of CP therapy for COVID-19. This systematic review was designed to evaluate the existing evidence and experience related to CP immunotherapy for COVID-19. METHODS: A literature search was conducted on Pubmed, Cochrane Library, Clinical Key, Wanfang Database; China National Knowledge Infrastructure(CNKI) were used to search for the proper keywords such as SARS-CoV-2, COVID-19, plasma, serum, immunoglobulins, blood transfusion, convalescent, novel coronavirus, immune and the related words for publications published until 15.10.2020. Other available resources were also used to identify relevant articles. The present systematic review was performed based on PRISMA protocol. Data extraction and risk of bias assessments were performed by two reviewers. RESULTS: Based on the inclusions and exclusions criteria, 45 articles were included in the final review. First, meta-analysis results of RCTs showed that, there were no statistically significant differences between CP transfusion and the control group in terms of reducing mortality(OR 0.79, 95% CI 0.52-1.19, I2 = 28%) and improving clinical symptoms(OR 1.21, 95%CI 0.68-2.16; I2 = 0%). The results of controlled NRSIs showed that CP therapy may reduce mortality in COVID-19 patients(RR 0.59, 95% CI 0.53-0.66, I2 = 0%). Second, limited safety data suggested that CP is a well-tolerated therapy with a low incidence of adverse events. But, due to lack of safety data for the control group, it is really not easy to determine whether CP transfusion has an impact on moderate to serious AEs. Thirdly, for children, pregnant, elderly, tumor and immunocompromised patients, CP may be a well-tolerated therapy, if the disease cannot be controlled and continues to progress. Studies were commonly of low or very low quality. CONCLUSIONS: Although the results of limited RCTs showed that CP cannot significantly reduce mortality, some non-RCTs and case report(series) have found that CP may help patients improve clinical symptoms, clear the virus, and reduce mortality, especially for patients with COVID-19 within ten days of illness. We speculate that CP may be a possible treatment option. High-quality studies are needed for establishing stronger quality of evidence and pharmacists should also be actively involved in the CP treatment process and provide close pharmaceutical care.


Assuntos
Antivirais/uso terapêutico , /terapia , Plasma/metabolismo , /virologia , Humanos , Imunização Passiva , Pandemias/prevenção & controle , /efeitos dos fármacos
9.
Int J Immunopathol Pharmacol ; 34: 2058738420974893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33259259

RESUMO

Periodontitis is an inflammatory disease caused by host immune response, resulting in a loss of periodontium and alveolar bone. Immune cells, such as T cells and macrophages, play a critical role in the periodontitis onset. Halofuginone, a natural quinazolinone alkaloid, has been shown to possess anti-fibrosis, anti-cancer, and immunomodulatory properties. However, the effect of halofuginone on periodontitis has never been reported. In this study, a ligature-induced mice model of periodontitis was applied to investigate the potential beneficial effect of halofuginone on periodontitis. We demonstrated that the administration of halofuginone significantly reduced the expression levels of pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α) in vivo, and markedly suppressed immune cell infiltration into the infected sites. Furthermore, we also observed that halofuginone treatment blocked the T-helper 17 (Th17) cell differentiation in vivo and in vitro. We demonstrated for the first time that halofuginone alleviated the onset of periodontitis through reducing immune responses.

10.
J Agric Food Chem ; 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267575

RESUMO

Dietary supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) for laying hens enriches eggs with these essential fatty acids. However, the enrichment patterns and changes to intact lipids in egg yolk have not been sufficiently revealed. Herein, egg yolk lipids from hens fed with diets supplemented with flaxseed, Schizochytrium sp. residue, or their mixture were comprehensively analyzed using ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). A total of 335 individual lipid species covering 23 (sub)classes were identified and quantified. Distinct n-3 PUFA-lipid profiles were revealed among different groups. Dietary α-linolenic acid (ALA) was mainly deposited in the TAG fraction, whereas synthesized or preformed docosahexaenoic acid (DHA) predominantly existed in the glycerophospholipid form. Furthermore, different lipid species were identified and related lipid pathways after dietary supplementation were analyzed. Collectively, these findings provide us with new knowledge for production, nutritional evaluation, authentication, and application of n-3 PUFA-enriched eggs.

11.
FASEB J ; 2020 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-33225469

RESUMO

Diabetic kidney disease (DKD) is a major cause of end stage renal diseases worldwide. Despite successive interventions for delaying the progression of DKD, current treatments cannot reverse the pathological progression. Mefunidone (MFD) is a new compound with potent antifibrotic properties, but the effect of MFD on DKD remains unknown. Therefore, we investigated the protective effects of MFD in both models of the db/db type 2 diabetes (T2D) and streptozotocin (STZ)-induced type 1 diabetes (T1D) models. Compared with the model group, MFD treatment significantly reduced pathological changes observed by PAS staining, PASM staining, and Masson staining in vivo. To further elucidate the potential mechanisms, we discovered MFD treatment notably restored podocyte function, alleviated inflammation, abated ROS generation, inhibited the TGF-ß1/SAMD2/3 pathway, suppressed the phosphorylation levels of MAPKs (ERK1/2, JNK, and P38), and reduced epithelial-to-mesenchymal transition(EMT). In conclusion, these findings demonstrate the effectiveness of MFD in diabetic nephropathy and elucidate its possible mechanism.

12.
Pak J Pharm Sci ; 33(3): 953-960, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33191218

RESUMO

Atractylodis rhizoma is a frequently-used traditional Chinese medicine in clinical practice, which have the effect of eliminating dampness and tonifying spleen. And after being processed with wheat bran, the dryness of A. rhizoma is reduced, and the function of tonifying spleen is enhanced. Atractylenolides are the major bioactive components of A. rhizoma, including atractylenolide I (AI), atractylenolide Ⅱ (AⅡ) and atractylenolide Ⅲ (AⅢ). The present study aimed to develope a new UPLC-MS/MS method for simultaneous quantification of three atractylenolides in rat urine, and applied to the excretory kinetics in Sprague-Dawley rats after oral administration of crude and processed A. rhizoma extracts. Analytes and internal standard were detected without interference in the multiple reaction monitoring (MRM) mode with positive electrospray ionization. The excretory kinetics parameters were calculated by a urine drug analysis model of drug and statistics (DAS) 3.2.8 software. The t1/2 and Ke of three atractylenolides had no significant difference between crude and processed A. rhizoma, but the recovery accumulative excretion of them in processed A. rhizoma were apparently higher than the crude ones (p<0.05, p<0.01). The results showed that only a small amount of atractylenolides excreted in urine and processing A. rhizoma with wheat bran by stir frying could promote the urinary excretion of them.

13.
Org Lett ; 22(22): 8860-8865, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33172271

RESUMO

A method for the synthesis of fused chromeno quinolines by the palladium/copper cocatalyzed C-H bond activation and C-C bond cleavage reaction has been developed. A variety of fused chromeno quinoline derivatives could be synthesized by coumarin derivatives and anilines through the C-C bond cleavage/C-H functionalization/C-C bond formation process. The MTT assay was used to evaluate the chromeno quinolines against the human cervix tumor cells (HeLa), 3c and 9c without coordination metals showed good inhibition effect.

14.
Langmuir ; 36(47): 14288-14295, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201711

RESUMO

In this work, a novel Pickering emulsion is stabilized by silica nanoparticles functioned with a redox and pH-responsive surfactant FA-DMDA-Ox that is prepared simply by direct neutralization of ferrocenecarboxylic acid (FA) and N,N-dimethyldodecylamine (DMDA) and exhibits redox and doubly pH-switchable behavior. Here, the Pickering emulsion can be stabilized easily by combining hydrophilic silica nanoparticles with less than 0.1 wt % FA-DMDA-Ox. After adding Na2SO3 and H2O2 alternately, the demulsification and emulsification of this Pickering emulsion are controlled reversibly. Moreover, the emulsion is switched "off" upon the addition of HCl and switched "on" upon the addition of NaOH and is also switched off upon the addition of NaOH and switched on upon the addition of HCl, which demonstrate the doubly pH-switchable behavior. Based on the analysis of ζ-potential, contact angle, and adsorbed amount of silica nanoparticles, the pH and redox-switchable mechanism of the Pickering emulsion are analyzed. Here, the redox-switchable behavior is induced by the reversible adsorption and desorption of FA-DMDA-Ox on the surface of silica nanoparticles. The pH-switchable behavior is driven by the controllable dispersion systems of silica nanoparticles and FA-DMDA-Ox because of the doubly pH switchability of FA-DMDA-Ox. More importantly, upon adding fresh oil after removing the original oil, the Pickering emulsion is recycled three times. Hence, the multiswitchable Pickering emulsion can be expected to be treated as a multifunctional material in practical applications, such as oil or wax removal in the petroleum industry.

15.
Sci Rep ; 10(1): 20112, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208871

RESUMO

Consistent use of large amounts of fertilizers, pesticides, and mulch can cause the accumulation of harmful substances in cotton plants. Among these harmful substances, cadmium (Cd), an undegradable element, stands out as being particularly highly toxic to plants. The objective of this study was to evaluate the ability of biochar (3%) and biofertilizer (1.5%) to decrease Cd uptake, increase cotton dry weight, and modulate the activities of photosynthetic and peroxidase (POD), superoxide dismutase (SOD), catalase enzyme (CAT) in cotton (Gossypium hirsutum L.) grown in Cd-contaminated soil (0, 1, 2, or 4 mg Cd kg-1 soil) in pots. These studies showed that, as expected, exogenous Cd adversely affects cotton chlorophyll and photosynthesis. However, biochar and biofertilizer increased cotton dry weight by an average of 16.82% and 32.62%, respectively. Meanwhile, biochar and biofertilizer decreased the accumulation of Cd in cotton organs, and there was a significant reduction in the amount of Cd in bolls (P < 0.05). Biochar and biofertilizer have a positive impact on cotton chlorophyll content, net photosynthesis, stomatal conductance, transpiration rate, and intercellular CO2 concentration. Thus, the addition of biochar and biofertilizer promote cotton growth. However, biochar and biofertilizer increased the SOD activity of leaves (47.70% and 77.21%), CAT activity of leaves (35.40% and 72.82%), SOD activity of roots (33.62% and 39.37%), and CAT activity of roots (36.91% and 60.29%), respectively, and the addition of biochar and biofertilizer decreased the content of MDA and electrolyte leakage rate. Redundancy analyses showed that biochar and biofertilizer also improved SOD and POD activities by reducing the heavy metal-induced oxidative stress in cotton and reducing Cd uptake in cotton organs. Therefore, biochar and biofertilizer have a positive effect on the growth of cotton.

16.
Neurocrit Care ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33174150

RESUMO

BACKGROUND/OBJECTIVES: To propose a novel definition for hydrocephalus growth and to further describe the association between hydrocephalus growth and poor outcome among patients with intracerebral hemorrhage (ICH). METHODS: We analyzed consecutive patients who presented within 6 h after ICH ictus between July 2011 and June 2017. Follow-up CT scans were performed within 36 h after initial CT scans. The degree of hydrocephalus were evaluated by the hydrocephalus score of Diringer et al. The optimal increase of the hydrocephalus scores between initial and follow-up CT scan was estimated to define hydrocephalus growth. Poor long-term outcome was defined as a modified Rankin Scale of 4-6 at 3 months. Multivariate logistic regression analysis was performed to investigate the hydrocephalus growth for predicting 30-day mortality, 90-day mortality, and poor long-term outcome. RESULTS: A total of 321 patients with ICH were included in the study. Of 64 patients with hydrocephalus growth, 34 (53.1%) patients presented with both concurrent hematoma expansion and intraventricular hemorrhage (IVH) growth. After adjusting for potential confounding factors, hydrocephalus growth independently predicted 30-day mortality, 90-day mortality, and 90-day poor long-term outcome in multivariate logistic regression analysis. Hydrocephalus growth showed higher accuracy for predicting 30-day mortality, 90-day mortality, and poor long-term outcome than IVH growth or hematoma expansion, respectively. CONCLUSIONS: Hydrocephalus growth is defined by strongly predictive of short- or long-term mortality and poor outcome at 90 days, and might be a potential indicator for assisting clinicians for clinical decision-making.

17.
Analyst ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33165453

RESUMO

We herein developed a new class of carborhodamines (CRs), i.e. 10-methoxy-substituted carborhodamines MCRs, by a simple synthesis procedure, which have absorption and emission wavelengths longer than classical CRs while retaining their excellent photophysical properties. Based on the MCR platform, we constructed the mitochondria-targeted fluorescent probe MCR-DMA and demonstrated its potential for sensing singlet oxygen (1O2) in living cells during the photodynamic therapy process.

18.
J Am Chem Soc ; 142(49): 20594-20599, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33252234

RESUMO

A dual platform for forging sp2-sp3 and sp3-sp3 carbon bonds via catalytic ß-scission of aliphatic alcohol derivatives with both aryl and alkyl halides is disclosed. This protocol is distinguished by its wide substrate scope and broad applicability, even in the context of late-stage functionalization.

19.
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.

20.
Org Biomol Chem ; 18(40): 8141-8146, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33016295

RESUMO

A simple and efficient synthetic protocol for the preparation of acridinium esters and amides through the cyclization and esterification or amidation of isatins with alcohols or amines as nucleophiles in the presence of CF3SO3H is established. A series of polycyclic acridine derivatives bearing large π-conjugated systems were obtained in high yields, including some key intermediates for the synthesis of biologically active molecules. The photophysical properties of these synthesized acridines were investigated, demonstrating that the sulfur heterocyclic acridine 9w was obtained in a high quantum yield.

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