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1.
J Org Chem ; 81(4): 1704-11, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26757405

RESUMO

The first facile and efficient silver-catalyzed, aldehyde-induced three-component reaction of N-unprotected tetrahydroisoquinolines, aldehydes, and dialkyl phosphonates has been developed, providing a general one-step approach to structurally diverse C1-phosphonylated THIQs accompanied by concurrent C-P bond formation/N-alkylation with remarkable functional group tolerance and excellent regioselectivity for endo products.

2.
J Org Chem ; 80(13): 6908-14, 2015 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-26062688

RESUMO

A novel and efficient palladium-catalyzed domino addition-cyclization of a wide range of arylboronic acids with various 3-hydroxyprop-1-yn-1-yl phosphonates has been developed, affording a convenient and powerful tool for the preparation of valuable 1,2-oxaphospholenes with mild reaction conditions, broad substrate applicability, and good to excellent yields. Mechanistic studies revealed that the reaction might involve Michael addition and nucleophilic substitution.


Assuntos
Ácidos Borônicos/química , Organofosfonatos/química , Compostos Organofosforados/síntese química , Ciclização , Estrutura Molecular , Compostos Organofosforados/química , Paládio
3.
Org Biomol Chem ; 13(30): 8221-31, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26134745

RESUMO

The first facile and practical silver-mediated cascade reaction of arylpropiolic acids with diarylphosphine oxides has been developed, providing a general, one step approach to structurally sophisticated 2-phosphinobenzo[b]phosphole oxide frameworks of importance in materials science via sequential decarboxylative C-P cross-coupling and C-H/P-H functionalization with operational simplicity and excellent functional group compatibility.


Assuntos
Química Orgânica/métodos , Óxidos/síntese química , Fosfinas/síntese química , Prata/química , Cristalografia por Raios X , Descarboxilação , Isomerismo , Oxirredução , Óxidos/química , Fosfinas/química , Enxofre/química
4.
J Org Chem ; 79(6): 2733-8, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24559491

RESUMO

The first example of Pd-catalyzed Suzuki cross-coupling of readily available arylhydrazines with arylboronic acids via C-N bond cleavage was developed under air, affording various biaryl compounds with broad substrate applicability and moderate to good yields. Moreover, the rigorous exclusion of air/moisture is not required in these transformations. Thus, the protocol represents a simple and efficient procedure to access biaryl compounds.


Assuntos
Ácidos Borônicos/química , Hidrazinas/química , Hidrazinas/síntese química , Paládio/química , Catálise , Estrutura Molecular
5.
Org Biomol Chem ; 12(18): 2895-902, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24671217

RESUMO

We present a novel and highly efficient methodology that allows for the construction of C-P bonds via the palladium-catalyzed air-based oxidative coupling of various commercially available arylboronic acids with easily oxidized H-phosphine oxides leading to valuable aryl phosphine oxides, particularly triarylphosphine oxides, with the use of air as the green oxidant, broad substrate applicability and good to excellent yields. The described catalytic system should be an efficient complement to the Chan-Lam type reaction and be useful in synthetic programs.


Assuntos
Ar , Ácidos Borônicos/química , Acoplamento Oxidativo , Óxidos/química , Paládio/química , Fosfinas/química , Catálise
6.
Neuroreport ; 35(10): 601-611, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38813902

RESUMO

Danshen injection (DI) is effective in treating cardiovascular and cerebrovascular diseases, including ischemic stroke (IS), including IS, but its mechanism is unclear. A middle cerebral artery occlusion model was used to simulate ischemia/reperfusion (I/R) injury in SD rats. Overexpression of hypoxia-inducible factor 1α (HIF-1α) was achieved by AAV-HIF-1α. Rats were treated with DI or saline. Neurological scores and infarction rates were assessed. I/R damage was examined by HE, 2,3,5-triphenyltetrazolium and Nissl stainings. Expression levels of relative proteins [TNF-α, IL-6, IL-1ß, SOD, MDA, ROS, HIF-1α, CXC chemokine receptor 4 (CXCR4) and NF-κB] were measured. DI treatment improved neurological scores and reduced infarction rates, suggesting that it inhibits inflammation and oxidative stress. The expression levels of HIF-1α, CXCR4 and NF-κB were decreased. However, the effectiveness of DI on inflammation inhibition was lost after HIF-1α overexpression. DI may directly target HIF-1α to suppress neuroinflammation and reduce I/R injury by suppressing the HIF-1α/CXCR4/NF-κB signaling pathway.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , NF-kappa B , Doenças Neuroinflamatórias , Ratos Sprague-Dawley , Receptores CXCR4 , Traumatismo por Reperfusão , Salvia miltiorrhiza , Transdução de Sinais , Animais , Receptores CXCR4/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Ratos , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/tratamento farmacológico
7.
Brain Behav ; 14(9): e70039, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39295108

RESUMO

BACKGROUND: Hypoxia inducible factor-1α (HIF-1α) is a sensitive indicator of oxygen homeostasis, of which the expression elevates following hypoxia/ischemia. This study reveals the specific mechanisms underlying the effects of HIF-1α on ischemic stroke (IS). METHODS: IS model was established using middle cerebral artery occlusion (MCAO)-modeled male rats and oxygen glucose deprivation/reoxygenation (OGD/R)-treated mice hippocampal cells HT22, followed by the silencing of HIF-1α and the overexpression of C-X-C motif chemokine receptor 4 (CXCR4) and nuclear factor-kappa B (NF-κB). Following the surgery, Garcia's grading scale was applied for neurological evaluation. Cerebral infarcts and injuries were visualized using 2,3,5-triphenyltetrazolium chloride and hematoxylin-eosin staining. The levels of tumor necrosis factor-α, Interleukin (IL)-6, IL-1ß, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine, were calculated via ELISA. MTT assay and lactate dehydrogenase (LDH) assay kit were adopted to determine the viability and cytotoxicity of OGD/R-modeled cells. Reactive oxygen species (ROS) generation was evaluated using a 2'-7'dichlorofluorescin diacetate (DCFH-DA) probe. The levels of HIF-1α, CXCR4, and NF-κB p65 were quantified via Western blot and immunofluorescence, respectively. RESULTS: HIF-1α knockdown improved Garcia's score, attenuated the cerebral infarct, inflammation, and ROS generation, and alleviated the levels of inflammatory cytokines and CXCR4/NF-κB p65 in MCAO-modeled rats. Such effects were reversed following the overexpression of CXCR4 and NF-κB. Also, in OGD/R-treated HT22 cells, HIF-1α silencing diminished the cytotoxicity and ROS production and reduced the expressions of CXCR4/NF-κB p65, while promoting viability. However, CXCR4/NF-κB p65 overexpression did the opposite. CONCLUSION: HIF-1α knockdown alleviates inflammation and oxidative stress in IS through the CXCR4/NF-κB pathway.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Inflamação , AVC Isquêmico , NF-kappa B , Estresse Oxidativo , Ratos Sprague-Dawley , Receptores CXCR4 , Animais , Masculino , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Ratos , Estresse Oxidativo/fisiologia , NF-kappa B/metabolismo , AVC Isquêmico/metabolismo , AVC Isquêmico/genética , Inflamação/metabolismo , Camundongos , Transdução de Sinais/fisiologia , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/genética , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Silenciamento de Genes
8.
Int J Gen Med ; 15: 2669-2680, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35300145

RESUMO

Purpose: Post-traumatic stress disorder (PTSD) is a result of trauma exposure and is related to psychological suffering as a long-lasting health issue. Further analysis of the networks and genes involved in PTSD are critical to the molecular mechanisms of PTSD. Methods: In this study, we aimed to identify key genes and molecular interaction networks involved in the pathogenesis of PTSD by integrating mRNA and miRNA data. Results: By integrating three high-throughput datasets, 5606 differentially expressed genes (DEGs) were detected, including five differentially expressed miRNAs (DEmiRNAs) and 5525 differentially expressed mRNAs (DEmRNAs). Nineteen upregulated and 46 downregulated DEmRNAs were identified in both GSE64813 and GSE89866 datasets, while five upregulated DEmiRNAs were found in the GSE87768 dataset. Functional annotations of these DEmRNAs indicated that they were mainly enriched in blood coagulation, cell adhesion, platelet activation, and extracellular matrix (ECM)-receptor interaction. Integrated protein-protein and miRNA-protein interaction networks among the DEGs were established with the help of 65 nodes and 121 interactions. Finally, 286 small molecules were obtained based on the Drug-Gene Interaction database (DGIdb). Three genes, prostaglandin-endoperoxide synthase 1 (PTGS1), beta-tubulin gene (TUBB1), and cyclin-dependent kinase inhibitor 1A (CDKN1A), were the most promising targets for PTSD therapy. Additionally, the present study also provided a higher performance diagnostic model for PTSD based on 17 DEmRNAs, which was validated in two independent datasets, GSE109409 and GSE63878. Conclusion: Our data provides a new molecular aspect that ECM-receptor interaction and the platelet activation process could be the potential molecular mechanism of PTSD, and the genes involved in this process may be promising therapeutic targets. A higher-performance diagnostic model for PTSD has also been identified.

10.
Chem Commun (Camb) ; 52(13): 2815-8, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26779577

RESUMO

The first metal-free, efficient TBAI-catalyzed radical addition/cyclization of diaryl(arylethynyl)phosphine oxides with toluene derivatives has been developed, affording a general, one-step approach to structurally sophisticated benzo[b]phosphole oxides via sequential C-H functionalization along with the formation of two new C-C bonds.

11.
Org Lett ; 18(23): 6066-6069, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27934373

RESUMO

The first facile and efficient copper-catalyzed direct C-P cross-coupling of unprotected propargylic alcohols with P(O)H compounds has been developed, providing a general, one-step approach to construct valuable allenylphosphoryl frameworks with operational simplicity and high step- and atom-economy under ligand-, base-, and additive-free conditions.

12.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 4): o238-9, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26029433

RESUMO

The title compound, C18H22N2O5, was synthesized by nitrification of its enol precursor. The pyrrolidine ring plane adopts a twisted conformation about the C-C bond linking the spiro centre and the C=O group remote from the N atom. It makes dihedral angles of 71.69 (9) and 88.92 (9)°, respectively, with the benzene ring plane and the plane defined by the four C atoms that form the seat of the of the cyclo-hexane chair. At the spiro centre, the NH group is axial and the C=O group is equatorial with respect to the cyclo-hexane ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R 2 (2)(8) loops. The dimers are linked by C-H⋯O inter-actions, generating a three-dimensional network.

13.
Org Lett ; 16(17): 4464-7, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25141945

RESUMO

A novel and efficient copper-catalyzed decarboxylative cross-coupling of alkynyl acids for the stereoselective synthesis of E-alkenylphosphine oxides has been developed. In the presence of 10 mol % of CuCl without added ligand, base, and additive, various alkynyl acids reacted with H-phosphine oxides to afford E-alkenylphosphine oxides with operational simplicity, broad substrate scope, and the stereoselectivity for E-isomers.


Assuntos
Alcenos/síntese química , Alcinos/química , Ácidos Carboxílicos/química , Cobre/química , Óxidos/síntese química , Fosfinas/síntese química , Alcenos/química , Alcinos/síntese química , Catálise , Descarboxilação , Ésteres , Óxidos/química , Fosfinas/química , Estereoisomerismo
14.
Org Lett ; 15(20): 5362-5, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24099283

RESUMO

A novel and efficient Ni-catalyzed coupling of a wide range of arylboronic acids with H-phosphites, H-phosphinate esters, and H-phosphine oxides has been developed, providing a general and powerful tool for the synthesis of various aryl-phosphorus compounds, especially for valuable triarylphosphine oxides, in good to excellent yield. This protocol is the first Ni-catalyzed C-P bond-forming reaction between arylboronic acids and P(O)H compounds.


Assuntos
Ácidos Borônicos/química , Níquel/química , Compostos Organometálicos/química , Compostos Organofosforados/síntese química , Ácidos Fosfínicos/química , Fosfitos/química , Catálise , Estrutura Molecular , Compostos Organofosforados/química
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