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1.
Chemistry ; 29(62): e202302249, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37572319

RESUMO

A novel one-pot two-step multicomponent reaction has been achieved for the preparation of ß-CF3 enamines by using different aliphatic amines, propiolates, and CF3 SO2 Na as starting material. In this protocol, various aliphatic amines including primary amines, cyclic or acyclic secondary amines were demonstrated to be good coupling partners, and different ß-CF3 enamines were obtained in moderate to good yields. Among them, the primary aliphatic amines only gave pure (E)-ß-CF3 enamines as products. The synthetic utility of the MCRs strategy was further demonstrated by mild conditions, gram-scale synthesis and natural sunlight-induced protocol. Preliminary mechanistic studies suggest that this trifluoromethylation of C(sp2 )-H involves radical process.

2.
Molecules ; 28(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37110617

RESUMO

A green one-pot 2,3,6-trifunctionalization of N-alkyl/aryl indoles was achieved by adding three equivalents of N-Br sulfoximine to the indole solution. A variety of 2-sulfoximidoyl-3,6-dibromo indoles were prepared with 38-94% yields using N-Br sulfoximines as both brominating and sulfoximinating reagents. Based on the results of controlled experiments, we propose that a radical substitution involving 3,6-dibromination and 2-sulfoximination occurs in the reaction process. This is first time that 2,3,6-trifunctionalization of indole in one pot has been achieved.

3.
Org Biomol Chem ; 20(12): 2356-2369, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35262140

RESUMO

Enaminones and analogous stable enamines are well known as platform building blocks in organic synthesis for the construction of heterocyclic compounds, especially N-heterocycles. To date, enaminones have been successfully employed in the synthesis of various 5- or 6- membered heterocycles. Recently, synthetic protocols accomplished by diversity-oriented annulation reactions based on the C-N bond cleavage of enamines have gained notable success. In this review, the development of the transition metal-free heterocyclic product synthesis based on the annulation reactions of enaminones or analogous enamines featuring a C-N bond cleavage is reviewed.


Assuntos
Compostos Heterocíclicos , Elementos de Transição , Técnicas de Química Sintética , Compostos Heterocíclicos/química , Elementos de Transição/química
4.
Org Biomol Chem ; 19(36): 7914-7919, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549232

RESUMO

A new two-step one-pot aminobromination/chlorination of carbonyl alkynes has been achieved via a Michael addition of aliphatic secondary amines and subsequent ß-bromination/chlorination of the obtained enamines to afford various α-X (X = Br or Cl) enamino ketones/esters in moderate to good yields. A solvent-controllable protocol has been developed to produce versatile 3-(2,5-dioxopyrrolidin-1-yl)acrylates in moderate yields by using toluene as the solvent and chain alkyl propiolates as alkynyl substrates.

5.
Yi Chuan ; 43(8): 802-812, 2021 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-34413019

RESUMO

The genetically modified (GM) maize 'Shuangkang'12-5 has good insect resistance and herbicide tolerance, which is one of the first series of GM maizes obtained a safety certificate in China, and it has broad application prospect in the future. This study established an on-site rapid detection method for GM 'Shuangkang'12-5 based on recombinase polymerase amplification (RPA) technology, which primes and probe were designed according to the specific flank sequence. Then the best combination of primers and probe was obtained through a screeing process. The amplification results of fluorescence RPA can be directly visualized under blue light. The results showed that the visual detection system of GM 'Shuangkang'12-5 with high specificity, and the detection sensitivity of the method could reached 10 copies. Further research found that the RPA amplification system had a wide range of temperature (34℃-46℃). According to this property, the common self-heating warm pastes on the market were used replace the traditional heating instruments to stimulate the RPA.The results showed that the self-heating warm paste meets the temperature requirement of the RPA system. Finally, we combined the self-heating warm pastes with the RPA visual detection system to conduct on-site detection of GM 'Shuangkang'12-5, and compared the results with the detection results of qPCR. The detection showed that the results of on-site visual detection method established in this study were consistent with the detection results of the qPCR. Moreover, the visual detection method was more shorter in time and the final detection result was clear and easy to distinguish. The rapid on-site visual detection method for GM 'Shuangkang' 12-5 established in this study has high specificity, high sensitivity and convenience. It not only meets the needs of on-site rapid detection of GM 'Shuangkang'12-5, but also provides highlight for the development of other on-site rapid detection methods.


Assuntos
Recombinases , Zea mays , Primers do DNA , Técnicas de Amplificação de Ácido Nucleico , Nucleotidiltransferases , Zea mays/genética
6.
Environ Res ; 182: 109079, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31887468

RESUMO

The crude electronic waste (e-waste) recycling has caused severe contamination of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the local environment, begging the question of whether wildlife like birds living at e-waste sites are suffering from adverse effects. We examined several oxidative status markers and their relationships with hepatic concentrations of PCBs and PBDEs in common kingfisher (Alcedo atthis) that inhabit an e-waste site in South China. The results showed that the mean concentrations of ∑PCBs (19100 ng/g) and ∑PBDEs (507 ng/g) in kingfishers from e-waste site were several orders of magnitude higher than those in the species from a reference site. Correspondingly, hepatic concentrations of malondialdehyde (MDA) and reactive oxygen species (ROS) in kingfishers from the e-waste site were significantly higher than those detected in the reference population, suggesting oxidative distress in the birds breeding at the e-waste site. The activities of superoxide dismutase (SOD) and catalase (CAT) in the liver from the exposed group were significantly lower compared with the reference group, while the opposite trend was observed for glutathione peroxidase (GPx). Significantly positive correlations were observed between PCB or PBDE concentrations and the levels of MDA and ROS; while negative correlations were found for enzymatic activities of SOD and CAT. Overall, our results may suggest a potential linkage between exposure to e-waste-derived pollutants and elevated oxidative stress, thereby indicating a potential oxidative stress-related health effects in common kingfisher breeding at the e-waste site.


Assuntos
Resíduo Eletrônico , Éteres Difenil Halogenados , Estresse Oxidativo , Bifenilos Policlorados , Animais , Aves , Cruzamento , China , Monitoramento Ambiental , Éteres Difenil Halogenados/toxicidade , Bifenilos Policlorados/toxicidade
7.
Environ Res ; 169: 62-71, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30419430

RESUMO

There is growing evidence that exposure to persistent organic pollutants (POPs) is statistically associated with incidence of cardiovascular disease (CVD) or its risk factors. Decarbromodiphenyl ether (BDE-209) is a new POP which exists extensively in human tissues, but its potential effects on CVD have so far received less focus. The adhesion of circulating monocytes to endothelial cells is one of the critical underlying steps in the initiation and development of CVD. In the present study, we investigated the effect of BDE-209 on the adhesion of THP-1 monocytes to human aortic endothelial cells (HAECs) and identified the molecular mechanisms involved. Our results showed that 6.25, 12.5 and 25 µM of BDE-209 exposures caused significant increases in monocyte-endothelial cell adhesion, in a dose-dependent manner. Mechanistically, BDE-209 exposure increased the expression of intercellular adhesion molecule-1 (ICAM-1). Moreover, the up-regulation of ICAM-1 was accompanied by a decrease in the expression of microRNA-141 (miR-141). Furthermore, the up-regulation of ICAM-1 and the increased adhesion induced by BDE-209 could be reversed by miR-141 supplement. Taken together, our results show that BDE-209 potentiates monocyte-endothelial cell interaction via miR-141/ICAM-1 pathway in HAECs.


Assuntos
Éteres Difenil Halogenados/toxicidade , Molécula 1 de Adesão Intercelular/metabolismo , MicroRNAs , Células Cultivadas , Células Endoteliais , Endotélio Vascular , Éter , Humanos , Monócitos
8.
Gynecol Endocrinol ; 34(12): 1091-1096, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30182767

RESUMO

Epithelial-mesenchymal transition (EMT) plays a significant part in the pathogenesis of endometriosis by facilitating the migration and invasion abilities of cells. Integrin-linked kinase (ILK) increases the cell migration and invasion abilities by inducing the EMT. Eutopic and control endometrial stromal cells (EuSCs and CSCs) were isolated and cultured. Cell migration and invasion abilities were detected by transwell assays. Levels of proteins were detected by Western blot. EuSCs showed higher levels of ILK, N-cadherin, vimentin and stronger migration and invasion abilities. After transfection of siRNA-ILK, E-cadherin and keratin levels were increased while N-cadherin and vimentin levels were decreased in EuSCs. Besides that, the migration and invasion abilities of EuSCs were significantly decreased after transfection of siRNA-ILK. On the contrary, levels of ILK, N-cadherin and vimentin were increased while levels of E-cadherin and keratin were decreased simultaneously after transfecting CSCs with pEGFP-C1-ILK. Simultaneously, the migration and invasion abilities of CSCs were increased after transfection of pEGFP-C1-ILK. Our study verified that high expression of ILK enhanced the migration and invasion abilities of ESCs by facilitating the EMT. Given that ILK played crucial roles in the pathogenesis of endometriosis, it may be considered as a promising targeted therapy for endometriosis.


Assuntos
Endometriose/etiologia , Endométrio/citologia , Transição Epitelial-Mesenquimal , Proteínas Serina-Treonina Quinases/fisiologia , Adulto , Movimento Celular , Feminino , Humanos , Pessoa de Meia-Idade , Células Estromais/fisiologia , Adulto Jovem
9.
Neurochem Res ; 42(12): 3382-3389, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28852934

RESUMO

The sulfone dapsone is an old antibiotic used for the treatment of mycobacterial and protozoal infections. We postulated before that dapsone might possess biological activity exceeding its anti-infectious properties and that it could potentially be repurposed for the treatment of glioma. To test this hypothesis, we treated established and primary cultured glioma cells with dapsone or several dapsone analogues which we previously synthesized (D2-D5) and determined effects on proliferation, anchorage-independent growth and migration. While dapsone and its synthetic analogues D2-D5 displayed only modest anti-proliferative activity, important neoplastic features such as anchorage-independent growth, clonogenic survival and directed migration were significantly inhibited by dapsone treatment. Moreover, dapsone analogues D3, D4 and D5 yielded even enhanced anti-glioma activity against different pro-neoplastic features. Overall these data suggest that dapsone provides activity against glioma which can be further enhanced by molecular modifications. These compounds could potentially serve as a therapeutic adjunct to the treatment of gliomas in a repurposing approach.


Assuntos
Antibacterianos/uso terapêutico , Dapsona/química , Dapsona/farmacologia , Glioma/tratamento farmacológico , Humanos , Interleucina-8/metabolismo , Leucotrieno B4/antagonistas & inibidores , Receptores de Formil Peptídeo/efeitos dos fármacos
10.
Chemistry ; 21(38): 13221-4, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26332229

RESUMO

A new transition metal-free method for the preparation of substituted imidazoles from easy-to-handle amidine hydrochlorides and bromoacetylenes has been developed. The reactions proceed in air and use inexpensive K2 CO3 as base. Additions of 2,2'-bipyridine and water have beneficial effects on the product yields. Various di- and trisubstituted imidazoles have been prepared in good yields (up to 88 %).

11.
Chemistry ; 21(29): 10330-3, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26139012

RESUMO

In the presence of LiBr, a palladium/copper combination catalyzes dehydrogenative amidobrominations of acrylates with NH-sulfoximines, leading to N-vinylated products by dual NH/CH coupling, followed by oxidative enamide bromination. Mechanistically, the domino process is proposed to involve palladium(II) species as key intermediates. First synthetic applications of the products have been demonstrated.

13.
BMC Cardiovasc Disord ; 15: 153, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26577590

RESUMO

BACKGROUND: Intravascular ultrasound (IVUS) can be a useful tool during drug-eluting stents (DES) implantation as it allows accurate assessment of lesion severity and optimal treatment planning. However, numerous reports have shown that IVUS guided percutaneous coronary intervention is not associated with improved clinical outcomes, especially in non-complex patients and lesions. METHODS: We searched the literature in Medline, the Cochrane Library, and other internet sources to identify studies that compare clinical outcomes between IVUS-guided and angiography-guided DES implantation. Random-effects model was used to assess treatment effect. RESULTS: Twenty eligible studies with a total of 29,068 patients were included in this meta-analysis. The use of IVUS was associated with significant reductions in major adverse cardiovascular events (MACE, odds ratios [OR] 0.77, 95 % confidence intervals [CI] 0.71-0.83, P < 0.001), death (OR 0.62, 95 % CI 0.54-0.71, p < 0.001), and stent thrombosis (OR 0.59, 95 % CI: 0.47-0.73, P < 0.001). The benefit was also seen in the repeated analysis of matched and randomized studies. In stratified analysis, IVUS guidance appeared to be beneficial not only in patients with complex lesions or acute coronary syndromes (ACS) but also patients with mixed lesions or presentations (MACE: OR 0.69, 95 % CI: 0.60-0.79, p < 0.001, OR 0.81, 95 % CI 0.74-0.90, p < 0.001, respectively). By employing meta-regression analysis, the benefit of IVUS is significantly pronounced in patients with complex lesions or ACS with respect to death (p = 0.048). CONCLUSIONS: IVUS guidance was associated with improved clinical outcomes, especially in patients with complex lesions admitted with ACS. Large, randomized clinical trials are warranted to identify populations and lesion characteristics where IVUS guidance would be associated with better outcomes.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Ultrassonografia de Intervenção , Idoso , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Valor Preditivo dos Testes , Pontuação de Propensão , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
14.
J Asian Nat Prod Res ; 17(5): 586-94, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26053125

RESUMO

Resveratrol, a famous plant-derived polyphenolic phytoalexin, has been considered to play physiological roles such as antioxidative, neuroprotective, and anticancer effects in adults. However, its antioxidative activity and neuroprotective effect were seldom discussed in the embryonic system. In this study, the effect of resveratrol on chicken embryo development under high glucose and its underlying mechanism of resveratrol were investigated. High glucose administrated to chicken embryo at embryonic Day 1 induced stillbirth, growth retardation, and impaired blood vessel development on yolk sac. However, resveratrol supplementation before glucose exposure showed significant effect on decreasing the death rate, developmental damage, and vessel injury. In addition, oxidative stress was caused by high-glucose exposure, and resveratrol could rescue this high-glucose-induced oxidative stress. Moreover, the neural developmental marker paired box 3 was significantly decreased by high glucose and recovered by resveratrol. Cell cycle-regulated gene expression was also intervened by resveratrol. This study had found an association between resveratrol and hyperglycemia-induced embryonic damage, which suggested a potential protective effect of resveratrol on gestational diabetes.


Assuntos
Glucose/toxicidade , Fármacos Neuroprotetores/farmacologia , Estilbenos/farmacologia , Animais , Produtos Biológicos/farmacologia , Galinhas , Glucose/análise , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Resveratrol , Estilbenos/química
15.
Zhongguo Zhong Yao Za Zhi ; 40(3): 430-6, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26084165

RESUMO

The difference between three representative components of total salvianolic acids in pharmacodynamic activity were compared by three different pharmacological experiments: HUVECs oxidative damage experiment, 4 items of blood coagulation in vitro experiment in rabbits and experimental myocardial ischemia in rats. And the effects of contribution rate of each component were calculated by multi index comprehensive evaluation method based on CRITIC weights. The contribution rates of salvianolic acid B, rosmarinic acid and Danshensu were 28.85%, 30.11%, 41.04%. Apparent oil/water partition coefficient of each representative components of total salvianolic acids in n-octyl alcohol-buffer was tested and the total salvianolic acid components were characterized based on a combination of the approach of self-defined weighting coefficient with effects of contribution rate. Apparent oil/water partition coefficient of total salvianolic acids was 0.32, 1.06, 0.89, 0.98, 0.90, 0.13, 0.02, 0.20, 0.56 when in octanol-water/pH 1.2 dilute hydrochloric acid solution/ pH 2.0, 2.5, 5.0, 5.8, 6.8, 7.4, 7.8 phosphate buffer solution. It provides a certain reference for the characterization of components.


Assuntos
Benzofuranos/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Lactatos/farmacologia , Animais , Benzofuranos/química , Cinamatos/química , Depsídeos/química , Lactatos/química , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley , Solubilidade , Ácido Rosmarínico
16.
Amino Acids ; 46(10): 2427-33, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25030664

RESUMO

An efficient method for the synthesis of aminomethyl benzimidazoles is developed by using a one-pot batch reaction between amino acids and o-phenylenediamines. This reaction proceeds smoothly in an unmodified household microwave oven, even though scale-up is to 10 g. A desirable method for the quick synthesis of benzimidazoles, which are used as a kind of important intermediates in drug synthesis, is provided by the scale-up utilization of amino acid resource.


Assuntos
Benzimidazóis/síntese química , Aminoácidos/química , Benzimidazóis/química , Catálise , Indicadores e Reagentes , Micro-Ondas , Estrutura Molecular , Fenilenodiaminas/química , Estereoisomerismo
17.
J Org Chem ; 79(23): 11619-30, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25387225

RESUMO

1,3,5-Tri(1H-benzo[d]imidazol-2-yl)benzene derivatives, as a new kind of fluorescent chemosensor for the detection of nitroaromatic explosives, are designed and synthesized by simple N-hydrocarbylation. Among 16 obtained compounds, compound 4g has the best capability for detection of picric acid (PA), having good selectivity and high sensitivity. The detection of PA with 4g solution-coated paper strips at the picogram level is developed. A simple, portable, and low-cost method is provided for detecting PA in solution and contact mode.

18.
Mol Biol Rep ; 41(8): 5273-86, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24859975

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs, which silence target mRNA via cleavage or translational inhibition to function in regulating gene expression. MiRNAs act as important regulators of plant development and stress response. For understanding the role of miRNAs responsive to apple ring rot stress, we identified disease-responsive miRNAs using high-throughput sequencing in Malus × domestica Borkh.. Four small RNA libraries were constructed from two control strains in M. domestica, crabapple (CKHu) and Fuji Naga-fu No. 6 (CKFu), and two disease stress strains, crabapple (DSHu) and Fuji Naga-fu No. 6 (DSFu). A total of 59 miRNA families were identified and five miRNAs might be responsive to apple ring rot infection and validated via qRT-PCR. Furthermore, we predicted 76 target genes which were regulated by conserved miRNAs potentially. Our study demonstrated that miRNAs was responsive to apple ring rot infection and may have important implications on apple disease resistance.


Assuntos
Regulação da Expressão Gênica de Plantas , Malus/genética , MicroRNAs/genética , Doenças das Plantas/genética , Sequência de Bases , Resistência à Doença , Biblioteca Gênica , Inativação Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Sequências Repetidas Invertidas , MicroRNAs/metabolismo , Dados de Sequência Molecular , RNA de Plantas/genética , Análise de Sequência de RNA
19.
Zhongguo Zhong Yao Za Zhi ; 39(8): 1426-9, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25039176

RESUMO

Traditional Chinese medicine (TCM) composition is a multi-component multiple drug release system and more components preparation system. How to evaluate the drug release behavior of diversification has been a block for the modernization of TCM. This article through to study of more representative components of ginkgolides drug release and similarity analysis of more representative components of ginkgolides drug release behavior and use Weight coefficient method to integrate the multicomponent drug release curve. So it can provide the idea and method for drug evaluation of TCM component preparation.


Assuntos
Medicamentos de Ervas Chinesas/química , Ginkgolídeos/química , Cinética , Solubilidade
20.
Zhongguo Zhong Yao Za Zhi ; 39(6): 1002-6, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24956839

RESUMO

Microcrystalline cellulose and chitosan were applied to prepare ginkgolides component solid dispersions micro pill drug release unit and study the dissolution of GKS. Microcrystalline cellulose, chitosan as composite carrier, solvent method was used to prepare ginkgolides component solid dispersions. Differential scanning calorimetry was used to Characterization of ginkgolides component solid dispersions. Ginkgolides component solid dispersions as principle agent were prepared for micro-pellet. Comparison of different types, different doses of the adhesive, drug-polymer interactions, and disintegrating agent for the preparation of ginkgolides components of micro-pellet drug release unit, the optimum preparation ginkgolides components of micro-pellet drug release unit was screened by orthogonal design experiment. Preparation of ginkgolides components solid dispersions with microcrystalline cellulose and chitosan at ratio 1: 3. Drug cumulative dissolution was more than 80% in 60 min. Solid dispersion-micro-pellet drug release unit can significantly improve the dissolution of ginkgolides components, it has practical application value.


Assuntos
Composição de Medicamentos/métodos , Ginkgolídeos/química , Celulose/química , Quitosana/química
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