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1.
Chemistry ; 30(51): e202400655, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-38959118

RESUMO

A visible-light-induced cascade reaction is described for the one-pot synthesis of 6-hydroxyindoloquinazolinones using isatins (or isatins and isatoic anhydrides) and aliphatic carboxylic acids. The method provides 36 desired products in 33-96 % yield, exhibiting broad substrate scope and good functional group tolerance. This approach utilizes inexpensive and commercially available starting materials, enabling the direct construction of high-value complex structures under mild conditions without the need for photocatalyst, showcasing significant applicability and environmental friendliness.

2.
J Org Chem ; 89(2): 1285-1295, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38163337

RESUMO

A novel photoredox-catalyzed direct hydroacylation of benzylidenemalononitriles is described. In this method, aroyl chlorides are employed as a readily available and affordable source of acyl groups, while commercially available tris(trimethylsilyl)silane acts as both the hydrogen atom donor and electron donor. By eliminating the requirement for complex synthesis of acyl precursors and hydrogen atom-transfer (HAT) reagents, this approach offers a convenient and efficient strategy for the hydroacylation of benzylidenemalononitriles.

3.
J Org Chem ; 89(15): 10929-10938, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39034667

RESUMO

A photoredox-neutral radical-radical cross-coupling is described for the synthesis of 3-hydroxy-3-alkyloxindoles using isatins and benzyl carboxylic acids as substrates and 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as the photocatalyst. The method features a broad substrate scope and good functional group tolerance, providing 30 sterically hindered alcohols with moderate to excellent yields. This approach utilizes inexpensive and commercially available starting materials, avoiding the use of transition metals, extra oxidants/reductants, and harsh reaction conditions, showcasing significant applicability and environmental friendliness.

4.
Angew Chem Int Ed Engl ; 58(1): 118-124, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30421485

RESUMO

The combination of photoredox and enzymatic catalysis for the direct asymmetric one-pot synthesis of 2,2-disubstituted indol-3-ones from 2-arylindoles through concurrent oxidization and alkylation reactions is described. 2-Arylindoles can be photocatalytically oxidized to 2-arylindol-3-one with subsequent enantioselective alkylation with ketones catalyzed by wheat germ lipase (WGL). The chiral quaternary carbon center at C2 of the indoles was directly constructed. This mode of concurrent photobiocatalysis provides a mild and powerful strategy for one-pot enantioselective synthesis of complex compounds. The experiments proved that other lipases containing structurally analogous catalytic triad in the active site also can catalyze the reaction in the same way. This reaction is the first example of combining the non-natural catalytic activity of hydrolases with visible-light catalysis for enantioselective organic synthesis and it does not require any cofactors.


Assuntos
Técnicas de Química Sintética/métodos , Estereoisomerismo , Catálise , Humanos , Estrutura Molecular
5.
Cell Death Dis ; 14(10): 696, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875515

RESUMO

As a common malignant tumor among women, ovarian cancer poses a serious threat to their health. This study demonstrates that long non-coding RNA NRSN2-AS1 is over-expressed in ovarian cancer tissues using patient sample and tissue microarrays. In addition, NRSN2-AS1 is shown to promote ovarian cancer cell proliferation and metastasis both in vitro and in vivo. Mechanistically, NRSN2-AS1 stabilizes protein tyrosine kinase 2 (PTK2) to activate the ß-catenin pathway via repressing MG-53-mediated ubiquitinated degradation of PTK2, thereby facilitating ovarian cancer progression. Rescue experiments verify the function of the NRSN2-AS1/PTK2/ß-catenin axis and the effects of MG53 on this axis in ovarian cancer cells. In conclusion, this study demonstrates the key role of the NRSN2-AS1/PTK2/ß-catenin axis for the first time and explores its potential clinical applications in ovarian cancer.


Assuntos
Neoplasias Ovarianas , RNA Longo não Codificante , Humanos , Feminino , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Cateninas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Wnt/genética , Movimento Celular/genética , Quinase 1 de Adesão Focal/metabolismo
6.
Org Lett ; 22(3): 1076-1080, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31975600

RESUMO

A mild and effective method for asymmetric synthesis of C2-quaternary indolin-3-ones directly from 2-arylindoles by combining visible light photocatalysis and organocatalysis is described. In this reaction, 2-substituted indoles undergo photocatalyzed oxidative dearomatization, followed by an organocatalyzed asymmetric Mannich reaction with ketones or aldehydes. Products with opposite configurations are easily obtained in satisfactory yields with excellent enantio- and diastereoselectivity by employing readily available l- and d-proline as chiral organocatalysts.


Assuntos
Indóis/química , Luz , Prolina/química , Catálise , Estrutura Molecular , Oxirredução , Processos Fotoquímicos , Estereoisomerismo
7.
Am J Reprod Immunol ; 78(4)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28508429

RESUMO

PROBLEM: To explore whether cervical carcinoma cell-derived interleukin-27 (IL-27) modulates the angiogenesis of vascular endothelial cells. METHOD OF STUDY: The expression of IL-27 in cervical cancer tissues and cervical cell lines was analyzed by immunohistochemistry, ELISA and flow cytometry. Then, the effects of IL-27 on the proliferation and apoptosis-related molecules and angiogenesis in vitro of human umbilical vein endothelial cells (HUVECs) were investigated. Finally, in vivo experiment was performed to further confirm the effects of IL-27. RESULTS: Compared with cervicitis, the cervical cancer tissues highly expressed IL-27. Both HeLa and CaSki cells secreted IL-27, and HUVECs expressed low levels of IL-27 receptors (IL-27R). However, the co-culture of cervical cell lines and HUVECs led to a significant elevation of IL-27R on HUVECs. Co-culturing with IL-27-overexpressed HeLa cells downregulated Ki-67 and Bcl-2 and upregulated Fas expression in HUVECs. In addition, overexpression of IL-27 in HeLa cells and CasKi cells secreted less IL-8 and could further restrict angiogenesis compared with control cells in vitro. In the subcutaneous tumorous model of C57/BL6 mouse, there were decreased vessel density and tumor volume when inoculation with IL-27-overexpressed TC-1 cells. CONCLUSION: This study indicates that IL-27 secreted by cervical carcinoma cells restricts the angiogenesis in a paracrine manner in the pathogenesis of cervical cancer.


Assuntos
Células Endoteliais/fisiologia , Interleucina-27/metabolismo , Neoplasias Experimentais/imunologia , Receptores de Interleucina/metabolismo , Neoplasias do Colo do Útero/imunologia , Animais , Apoptose , Proliferação de Células , Técnicas de Cocultura , Feminino , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Interleucina-27/genética , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica , Comunicação Parácrina , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptor fas/metabolismo
8.
Yi Chuan ; 27(6): 1013-9, 2005 Nov.
Artigo em Zh | MEDLINE | ID: mdl-16378955

RESUMO

The granule-bound starch synthase(GBSS) is encoded by the rice Wx gene, which is the major gene for control of amylase synthesis of. This paper briefly introduced the progress in regulation of rice Wx gene expression at transcriptional level and post-transcriptional level. At the same time the influence of transgene, genetic background and temperature condition on Wx gene expression in rice was discussed. Finally some urgent questions were suggested for the further study on regulation of rice Wx gene expression.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Sintase do Amido/genética , Amilose/metabolismo , Inativação Gênica , Oryza/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Temperatura , Transcrição Gênica
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