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1.
Chemistry ; 27(14): 4715-4722, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33369774

RESUMO

Glycolic acid is a useful and important α-hydroxy acid that has broad applications. Herein, the homogeneous ruthenium catalyzed reforming of aqueous ethylene glycol to generate glycolic acid as well as pure hydrogen gas, without concomitant CO2 emission, is reported. This approach provides a clean and sustainable direction to glycolic acid and hydrogen, based on inexpensive, readily available, and renewable ethylene glycol using 0.5 mol % of catalyst. In-depth mechanistic experimental and computational studies highlight key aspects of the PNNH-ligand framework involved in this transformation.

2.
Chem Sci ; 11(27): 7188-7193, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34123004

RESUMO

A sustainable, new synthesis of oxalamides, by acceptorless dehydrogenative coupling of ethylene glycol with amines, generating H2, homogeneously catalyzed by a ruthenium pincer complex, is presented. The reverse hydrogenation reaction is also accomplished using the same catalyst. A plausible reaction mechanism is proposed based on stoichiometric reactions, NMR studies, X-ray crystallography as well as observation of plausible intermediates.

3.
Chemistry ; 26(67): 15487-15490, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33459426

RESUMO

Liquid organic hydrogen carriers (LOHCs) are powerful systems for the efficient unloading and loading molecular hydrogen. Herein, a liquid-to-liquid organic hydrogen carrier system based on reversible dehydrogenative coupling of ethylene glycol (EG) with ethanol catalysed by ruthenium pincer complexes is reported. Noticeable advantages of the current LOHC system is that both reactants (hydrogen-rich components) and the produced esters (hydrogen-lean components) are liquids at room temperature, and the dehydrogenation process can be performed under solvent and base-free conditions. Moreover, the hydrogenation reaction proceeds under low hydrogen pressure (5 bar), and the LOHC system has a relatively high theoretical gravimetric hydrogen storage capacity (HSC>5.0 wt %), presenting an attractive hydrogen storage system.

4.
Org Lett ; 20(2): 421-424, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29314848

RESUMO

A dual visible light photoredox and nickel-catalyzed cross-coupling reaction of 2-arylaziridines and potassium benzyltrifluoroborates is described for the first time. This strategy features high functional group tolerance, exclusive regioselectivity for reaction at the more hindered C-N bond, easily accessible substrates, and mild redox-neutral reaction conditions. A variety of diversely substituted ß-substituted amines are obtained in generally good yields.

5.
Org Lett ; 20(2): 461-464, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29313355

RESUMO

Efficient and enantioselective radical difluoroalkylation and perfluoroalkylation reactions of ß-ketoesters were successfully developed through an asymmetric photoredox and nickel catalysis cascade. This protocol provides Rf-containing quaternary stereocenters in up to 67% yield and 95:5 er with ethyl iododifluoroacetate and perfluoroalkyl iodides (C3F7I and C4F9I) as radical sources under extremely mild conditions.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(3): 692-5, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23815924

RESUMO

This study was aimed to explore the pathogenesis of type III familial hemophagocytic lymphohistiocytosis (FHL3) via susceptibility gene UNC13D involving in homologous recombination repair (HRR) of DNA double-strand break (DSB). By means of DNA homologous recombination repair, the change of homologous recombination repair rate of normal control cells and DR-U2OS cells after down-regulation of UNC13D was detected; the UNC13D gene related function was explored. The results showed that DR-U2OS cells displayed a significant reduction in homologous recombination repair of DNA DSB after siRNA knockdown of UNC13D, compared to its normal control cell counterparts (P < 0.05), suggesting that UNC13D was involved in DNA double-stranded breakage repair. It is concluded that UNC13D gene mutation may be involved in the pathogenesis of FHL3 via its dual effects of both the cytotoxic granule exocytosis and decrease of homologous recombination repair rate after the DNA double-strand break, therefore, providing a new theoretical basis to reveal the pathogenesis of FHL3.


Assuntos
Linfo-Histiocitose Hemofagocítica/genética , Proteínas de Membrana/genética , Reparo de DNA por Recombinação , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/genética , Humanos , Linfo-Histiocitose Hemofagocítica/classificação
7.
Zhonghua Xue Ye Xue Za Zhi ; 33(5): 371-7, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22781794

RESUMO

OBJECTIVE: To investigate the underlying tumor susceptibility mechanisms and reasons for the high risk of cancer in Fanconi anemia (FA). METHODS: Gene Set Enrichment Analysis (GSEA) was performed to compare gene expression profiles between 21 FA patients' bone marrow (BM) mononuclear cell (BMNC) and 11 normal controls in cancer related gene sets from NCBI GEO database, then core enriched genes were identified by further investigation. Through enrichment analyzing biological processes of gene ontology sets and structural genomic gene sets between FA expression profiles and control, more details related with its tumor susceptibility had been revealed. RESULTS: Compared with normal control, gene expression in FA group had significant been enriched in resistance to Bcl-2 inhibitor gene set, fibroblast growth factors signalling pathways, insulin and insulin-like growth factors (IGF) signalling pathways induced cancer genesis gene sets. The high level of D4S234E, SST, FGFs, IGFs, FGFRs and IGFBP expression provided an initiate environment for tumorgenesis and drug resistance. There were significant differences in biogenesis extracellular molecules and cytomembrane structure organizations between FA and control. Genes with promoter regions around transcription start sites containing either motif RRCAGGTGNCV or CCTNTMAGA were enriched and those former genes match annotation for tumorgenic transcription factor 3 (TCF3). CONCLUSIONS: The high tumor susceptibility of FA patients may be closely related with the dramatic changes in cancer related growth factors and hormones environment. This study provides new insights into tumor susceptibility mechanism in FA patients.


Assuntos
Anemia de Fanconi/genética , Genes Neoplásicos , Predisposição Genética para Doença , Neoplasias/genética , Transcriptoma , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Estudos de Casos e Controles , Feminino , Expressão Gênica , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Masculino , Regiões Promotoras Genéticas , Transdução de Sinais/genética , Somatomedinas/genética , Sítio de Iniciação de Transcrição
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