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1.
Org Biomol Chem ; 19(11): 2487-2491, 2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33656503

RESUMO

An efficient organophosphorus-mediated cross-Rauhut-Currier/Wittig domino reaction of vinyl ketones with chalcones has been developed for the synthesis of trisubstituted cyclopentenes. The new synthetic method has the advantages of mild reaction conditions, high efficiency, environmental friendliness and satisfactory yields.

2.
Org Biomol Chem ; 15(23): 4978-4983, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28560366

RESUMO

A novel cascade C-H functionalization/cyclization reaction of N-arylpyridin-2-amines with α,ß-unsaturated aldehydes has been developed under rhodium catalysis, affording dihydroquinolinone derivatives in moderate to excellent yields. A plausible mechanism of dual catalytic cycles by rhodium(iii) catalysis is also proposed.

3.
J Org Chem ; 81(11): 4429-33, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27186906

RESUMO

An intermolecular Morita-Baylis-Hillman (MBH) reaction of α,ß-unsaturated ketones with allylic acetates under the catalysis of 10 mol % of tetrakis(triphenylphosphine)palladium(0) and mediation of tributylphosphine has been developed in the presence of acetic acid, affording the desired α-coupling products. The MBH reaction has the advantages of good tolerance to many functional groups, excellent regioselectivity and E-stereoselectivity, and moderate to good yields.

4.
J Org Chem ; 80(18): 9354-9, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26334559

RESUMO

A new domino Heck-isomerization/Saegusa/Heck reaction of propenol with aryl iodides has been developed for the synthesis of 3,3-diaryl propenals by triple transition-metal catalysis. Moreover, we also developed the domino Heck-isomerization/Heck-type reaction of propenol with aryl iodides for the synthesis of 1,3-diaryl propanones by double transition-metal catalysis and the mediation of secondary amine or triple transition metal catalysis and aminocatalysis.

5.
Org Biomol Chem ; 13(15): 4466-72, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25773505

RESUMO

A novel DCC reaction between aromatic aldehydes or ketones and H-phosphonates has been developed for the synthesis of p-formyl or p-acylphenylphosphonates. The synthetic method has excellent para regioselectivities, good yields, and broad substrate scopes and is more benign to the environment. The DCC reaction also tolerates many functional groups, and results in a series of new p-formyl and p-acylphenylphosphonates, which should be important building blocks for the synthesis of versatile arylphosphonate derivatives.


Assuntos
Aldeídos/química , Hidrocarbonetos Aromáticos/química , Cetonas/química , Organofosfonatos/química , Acilação , Aldeídos/síntese química , Formiatos/síntese química , Formiatos/química , Hidrocarbonetos Aromáticos/síntese química , Cetonas/síntese química , Organofosfonatos/síntese química , Estereoisomerismo
6.
Chemistry ; 20(22): 6618-21, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24757128

RESUMO

A dehydrogenative cross-coupling reaction between allylic C-H bonds and the α-C-H bond of ketones or aldehydes was developed using Cu(OTf)2 as a catalyst and DDQ as an oxidant. This synthetic approach to γ,δ-unsaturated ketones and aldehydes has the advantages of broad scope for both ketones and aldehydes as reactants, mild reaction conditions, good yields and atom economy. A plausible mechanism using Cu(OTf)2 as a Lewis acid catalyst was also proposed (DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone; Tf=trifluoromethanesulfonate).

7.
Org Biomol Chem ; 12(31): 5839-42, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24995431

RESUMO

A cascade alkylarylation reaction of 2-isocyanobiphenyls with simple alkanes for 6-alkyl phenanthridines has been developed through dual C(sp(3))-H/C(sp(2))-H functionalizations. The synthetic method has the advantages of high yields, good compatibility of functional groups and mild reaction conditions, although very unreactive alkanes were involved in the reaction. A plausible mechanism through both copper-catalyzed and DTBP mediated pathways has also been proposed.

8.
Chemistry ; 19(3): 1129-33, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23150383

RESUMO

An efficient palladium-catalyzed C-H functionalization of aldehydes with various N-substituted N-heteroarene-2-carboxamides has been developed for the synthesis of secondary imides. The reaction tolerates various functionalities, such as methoxy, fluoro, chloro, and bromo groups. A tentative radical mechanism for a Pd(II)/Pd(IV) catalytic cycle is proposed.


Assuntos
Aldeídos/química , Amidas/química , Imidas/síntese química , Compostos Organometálicos/química , Paládio/química , Catálise , Imidas/química , Estrutura Molecular
9.
J Org Chem ; 77(18): 8344-9, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22920331

RESUMO

A new type of transesterification between aryl, heteroaryl, alkyl N-heteroarene-2-carboxylates and various aldehydes by C-H and C-O bond activations has been developed for the synthesis of versatile carboxylates. A possible mechanism containing oxidative addition of acyl-O bond in parent ester and radical cleavage of sp(2) C-H bond in aldehyde is proposed.

10.
J Org Chem ; 77(17): 7706-10, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22901007

RESUMO

A silver-catalyzed dehydrogenative cross-coupling reaction of substituted furans, thiophene, thioazole, and pyrrole 1a-e with dialkyl phosphites 2 was first developed to afford corresponding phosphonated products 3a-h with up to 89% yield and good regioselectivities. Moreover, an unprecedented coupling of various substituted pyridines 1f-k with dialkyl phosphites 2 using AgNO(3) as a catalyst and K(2)S(2)O(8) as an oxidant, followed by reduction with Na(2)S(2)O(3), was also realized to furnish desired pyridine phosphonates 3i-q in satisfactory yields with good regioselectivities.


Assuntos
Azóis/química , Furanos/química , Fosfitos/química , Pirróis/química , Prata/química , Tiofenos/química , Catálise , Estrutura Molecular , Organofosfonatos/síntese química , Organofosfonatos/química , Piridinas/síntese química , Piridinas/química
11.
Chemotherapy ; 57(2): 162-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21454974

RESUMO

BACKGROUND/AIMS: Coumarins are natural compounds found in many plants that possess medical value by itself and its modified derivatives. METHOD: Six novel coumarin derivatives were synthesized and examined for their potential anticancer cytotoxicity. RESULT: Among the 6 derivatives, 3,5-dimethyl-(7)H-furo[3,2-g]chromen-7-one (DMFC) presented the strongest cytotoxicity against human hepatoma HepG2 cells in vitro with an IC(50) value of 8.46 ± 0.28 µM in a 48-hour treatment. Further experiments revealed that DMFC induced apoptosis in HepG2 cells through both extrinsic and intrinsic apoptotic pathways in a p53-dependent manner. Mechanistically, DMFC activated caspases 3, 8 and 9, depolarized mitochondrial membrane potential and induced cytochrome c and apoptosis-inducing factor release. DMFC-induced apoptosis was also characterized by DNA fragmentation, phosphatidylserine externalization and sub-G1 peak in DNA histograms. Moreover, both caspase 8 and 9 inhibitors suppressed the apoptosis induced by DMFC. Western blot analyses revealed that DMFC also significantly increased the expression levels of p53, Fas death receptor, Fas-associated death domain protein and proapoptotic Bcl-2 family members such as Bax, Bad and tBid, as well as decreased the levels of pro-survival members such as Bcl-2 and Bcl-xl. CONCLUSION: DMFC is potentially an effective therapeutic agent in liver cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzofuranos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Cumarínicos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Fator de Indução de Apoptose/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Caspases/metabolismo , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fosfatidilserinas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Proteína bcl-X/biossíntese , Proteína bcl-X/genética , Receptor fas/biossíntese , Receptor fas/genética
12.
Yao Xue Xue Bao ; 46(1): 64-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21462896

RESUMO

It was found that psoralen derivative could perform a Friedel-Crafts acylation smoothly with acetic anhydride to give 5'-acetylpsoralen in a 73% yield. In the presence of boron trifluoride etherate, 5'-acetylpsoralen reacted with both aromatic amines and aliphatic amine smoothly to afford 5'-Schiff-base group substituted psoralen derivatives in 72%-92% yields. The novel synthetic method has the advantages of cheap materials, mild reaction conditions, good yields and high regioselectivity in the Friedel-Crafts acylation. Cell viability assay by MTT demonstrates that some of the psoralen derivatives 6 have antiproliferative activities.


Assuntos
Proliferação de Células/efeitos dos fármacos , Furocumarinas/síntese química , Furocumarinas/farmacologia , Acilação , Boranos/química , Linhagem Celular Tumoral , Furocumarinas/química , Humanos , Estrutura Molecular , Bases de Schiff/química
13.
Histol Histopathol ; 36(1): 101-112, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33215396

RESUMO

OBJECTIVE: To examine the effect of the BRD4 inhibitor JQ1 on mice with chronic obstructive pulmonary disease (COPD) via NF-κB. METHODS: COPD models constructed by exposure to cigarette smoke and intratracheal instillation of lipopolysaccharides (LPS) in mice were treated with JQ1 (15, 25 or 50 mg/kg). HE staining was performed to observe histopathological changes in the lung tissues. Enzyme-linked immunosorbent assays (ELISAs) were used to measure the levels of IL-10, IFN-γ, IL-17, IL-1ß, IL-6, TNF-α, MMP-2, MMP-9, MDA, SOD, T-AOC and HO-1, and gelatin zymography assays were used to examine MMP-2 and MMP-9 activity. A TransAMTM NF-κB p65 detection kit was used to test NF-κB p65/DNA binding activity. Western blotting was conducted to analyze NF-κB p65 in the nucleus and its acetylation. RESULTS: JQ1 dose-dependently improved the histopathological changes in the lung tissues and decreased the mean linear intercept (MLI), destructive index and inflammatory score of the mice with COPD. The mice with COPD showed increased levels of MMP-2, MMP-9, IFN-γ, IL-17, IL-1ß, IL-6 and TNF-α with decreased IL-10 level; these changes were reversed by JQ1 in a dose-dependent manner. In addition, JQ1 reduced the MDA level and increased the SOD, HO-1 and T-AOC levels in mice with COPD, with suppression of NF-κB p65 expression in the nucleus, NF-κB/p65 (Lys310) acetylation and NF-κB p65/DNA binding activity in the lung tissues. CONCLUSION: The BRD4 inhibitor JQ1 can downregulate MMP-2 and MMP-9 expression, reduce inflammatory responses, and alleviate oxidative stress in mice with COPD, and this mechanism might be related to the inhibition of NF-κB.


Assuntos
Azepinas/farmacologia , Subunidade p50 de NF-kappa B/biossíntese , Proteínas Nucleares/antagonistas & inibidores , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologia , Animais , Citocinas/metabolismo , Regulação da Expressão Gênica , Inflamação , Leucócitos/citologia , Lipopolissacarídeos/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Nucleares/genética , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Testes de Função Respiratória , Transdução de Sinais
14.
J Immunol Res ; 2020: 9382609, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32656270

RESUMO

Epidemiological studies have demonstrated that interleukin-10 (IL-10) polymorphisms may be associated with the development of Behcet's disease (BD). However, the published results were inconsistent. Therefore, this meta-analysis was conducted to derive a more precise relationship between IL-10 polymorphisms and BD susceptibility. Online databases (PubMed, Embase, Science Citation Index (SCI), CNKI, and WanFang) were searched to identify eligible studies. Odds ratio (OR) and a 95% confidence interval (CI) were applied to assess the relationship strength between IL-10 -1082A>G (rs1800896), -819T>C (rs1800871), and -592A>C (rs1800872) polymorphisms and BD susceptibility. Publication bias, sensitivity, and cumulative analyses were conducted to measure the robustness of our findings. Finally, fifteen articles (36 independent case-control studies) involving 5,971 patients and 8,913 controls were included. Overall, significant associations between -819T>C polymorphisms and BD risk were observed in the total population (C vs. T: OR = 0.72, 95%CI = 0.67-0.77, P < 0.01, I 2 = 36.6%; TC vs. TT: OR = 0.73, 95%CI = 0.66-0.80, P < 0.01, I 2 = 23.0%; CC vs. TT: OR = 0.52, 95%CI = 0.39-0.70, P < 0.01, I 2 = 53.7%; TC+CC vs. TT: OR = 0.67, 95%CI = 0.61-0.71, P < 0.01, I 2 = 22.1%; and CC vs. TT+TC: OR = 0.66, 95%CI = 0.53-0.82, P < 0.01, I 2 = 57.8%). Moreover, the IL-10 -592 A>C polymorphism and the ACC haplotype exhibited a significant, protective effect against BD susceptibility. In summary, our meta-analysis suggested that IL-10 gene polymorphisms may play a salient role for BD development.


Assuntos
Síndrome de Behçet/genética , Genótipo , Interleucina-10/genética , Polimorfismo de Nucleotídeo Único/genética , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Risco
15.
Chemistry ; 15(15): 3784-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19229932

RESUMO

As the first example of the application of chiral selenonium ylides in asymmetric cyclopropanation, a new strategy for the highly stereoselective synthesis of chiral 1,2,3-trisubstituted cyclopropanes via selenonium ylides is described. The reaction afforded three stereoisomers of chiral 1,2,3-trisubstituted cyclopropanes with good yields, excellent diastereoselectivities, very high enantioselectivities (up to >99% ee), good generality and recyclability of chiral selenides. The possible pathways and models of the asymmetric cyclopropanation via the chiral selenonium ylides were also proposed to rationalize the excellent enantioselectivities and diastereoselectivities.


Assuntos
Ciclopropanos/síntese química , Compostos Organosselênicos/química , Ciclopropanos/química , Estrutura Molecular , Estereoisomerismo
16.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 7): o1245, 2008 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21202880

RESUMO

The title compound, a seleno-nium bromide, C(17)H(33)OSeSi(+)·Br(-), was obtained from the reaction of enanti-omerically pure 4,7,7-trimethyl-2-methyl-selanylbicyclo-[2.2.1]heptan-3-ol and (3-bromopropen-yl)trimethyl-silane in acetone. Due to the chiral bicyclic substituent, the crystal structure is not centrosymmetric and has no symmetry plane, with four chiral C atoms in the cation. The asymmetric unit contains one seleno-nium cation and one bromide anion. C-H⋯Br and O-H⋯Br hydrogen bonds link the ions, forming a one-dimensional R-helical chain-like supra-molecular structure.

17.
Org Lett ; 19(23): 6265-6267, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29152971

RESUMO

A novel cascade DCC/annulation reaction of N-alkoxybenzamides with ß-keto esters has been developed for the synthesis of isoquinolinone derivatives under palladium catalysis. A plausible mechanism involving α-C(sp2)-H activation and a Pd(II)/Pd(IV) catalytic cycle is also proposed.

18.
Org Lett ; 19(6): 1374-1377, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28256839

RESUMO

A four-component cascade C-H functionalization/cyclization/nucleophilic substitution reactions of anilines, carboxylic anhydrides, propenol, and alkohols have been developed by a strategy of in situ directing group formation, affording an efficient and convenient synthesis of α-alkoxyl tetrahydroquinolines from basic starting materials. A plausible mechanism involving rhodium(III) catalytic C-H functionalization and double nucleophilic attacks is proposed. The nucleophilicity order of some alcohols is also obtained for the cascade reaction.

19.
Org Lett ; 18(7): 1526-9, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26984111

RESUMO

A novel dehydrogenative cross-coupling (DCC) reaction between N-arylglycine esters and phenols or 1,3,5-trimethoxybenzene was developed by copper catalysis using di-tert-butyl peroxide (DTBP) as an oxidant. Under optimized conditions, a range of N-arylglycine esters 1 underwent the DCC reaction smoothly with various phenols 2 or 1,3,5-trimethoxybenzene 4 to give desired α-aryl α -amino acid esters 3 or 5, respectively, with high ortho regioselectivities in a moderate to excellent yield. A possible mechanism involving aromatic electrophilic substitution is proposed.


Assuntos
Aminoácidos/química , Glicina/química , Fenóis/química , Floroglucinol/análogos & derivados , Catálise , Ésteres , Glicina/análogos & derivados , Estrutura Molecular , Floroglucinol/química
20.
Org Lett ; 18(13): 3058-61, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27308722

RESUMO

A cascade C-H functionalization/amidation reaction of aminobiaryls with diazomalonates has been developed under rhodium catalysis, affording new azepinone derivatives in moderate to excellent yields.

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