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1.
Org Lett ; 26(18): 3727-3732, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38678575

RESUMO

Photoexcitation electron donor-acceptor (EDA) complexes provide an effective approach to produce radicals under mild conditions, while the catalytic version of EDA complex photoactivation remains scarce. Herein, we report a visible-light-induced organophotocatalytic pathway for the cyanoalkylation of azauracils using inexpensive and readily available 1,4-diazabicyclo[2.2.2]octane (DABCO) as a catalytic electron donor. This synthetic method exhibits exceptional compatibility with various functional groups and presents 34 examples in high yields. The efficient cyanoalkylation offers an environmentally friendly and sustainable route toward enhancing the structural and functional diversity of azauracils.

2.
Chem Commun (Camb) ; 60(21): 2958-2961, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38375889

RESUMO

Visible-light-induced EDA complex-promoted ring-opening of cycloketone oxime esters to synthesise various cyanoalkylated products with N-methacryloyl benzamides was developed. Various radical receptors were compatible with the current reaction system to furnish diverse heterocyclic compounds. Mechanistic analysis shows that the formation of an EDA complex was crucial to the photocatalytic strategy. Importantly, 4-cyanoalkyl isoquinoline-1,3-diones were obtained in high yields by using a catalytic amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) through prolonging the reaction time, which provided a practical approach to give a variety of isoquinoline-1,3-dione derivatives.

3.
Org Biomol Chem ; 22(5): 965-969, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38205855

RESUMO

A visible-light-induced decarboxylative cascade reaction of acryloylbenzamides with alkyl N-hydroxyphthalimide (NHP) esters for the synthesis of various 4-alkyl isoquinolinediones mediated by triphenylphosphine (PPh3) and sodium iodide (NaI) was developed. This operationally simple protocol proceeded via the photoactivation of electron donor-acceptor (EDA) complexes between N-hydroxyphthalimide esters and NaI/PPh3, resulting in multiple carbon-carbon bond formations without the use of precious metal complexes or synthetically elaborate organic dyes, which provided an alternative practical approach to synthesize diverse isoquinoline-1,3(2H,4H)-dione derivatives.

4.
J Invertebr Pathol ; 203: 108066, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246321

RESUMO

Ameson portunus, the recently discovered causative agent of "toothpaste disease" of pond-cultured swimming crabs in China has caused enormous economic losses in aquaculture. Understanding the process of spore germination is helpful to elucidate the molecular mechanism of its invasion of host cells. Here, we obtained mature and germinating spores by isolation and purification and in vitro stimulation, respectively. Then, non-germinated and germinated spores were subjected to the comparative transcriptomic analysis to disclose differential molecular responses of these two stages. The highest germination rate, i.e., 71.45 %, was achieved in 0.01 mol/L KOH germination solution. There were 9,609 significantly differentially expressed genes (DEGs), with 685 up-regulated and 8,924 down-regulated DEGs. The up-regulated genes were significantly enriched in ribosome pathway, and the down-regulated genes were significantly enriched in various metabolic pathways, including carbohydrate metabolism, amino acid metabolism and other metabolism. The results suggested that spores require various carbohydrates and amino acids as energy to support their life activities during germination and synthesize large amounts of ribosomal proteins to provide sites for DNA replication, transcription, translation and protein synthesis of the spores of A. portunus within the host cells. Functional genes related to spore germination, such as protein phosphatase CheZ and aquaporin, were also analyzed. The analysis of transcriptome data and identification of functional genes will help to understand the process of spore germination and invasion.


Assuntos
Microsporídios , Transcriptoma , Animais , Esporos , Microsporídios/genética , Perfilação da Expressão Gênica , Esporos Bacterianos/genética
5.
Fish Shellfish Immunol ; 145: 109324, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134977

RESUMO

Ameson portunus (Microsporidia) has caused serious economic losses to the aquaculture industry of swimming crab, Portunus trituberculatus. The hemolymph and hepatopancreas are the main immune organs of P. trituberculatus, and the main sites of A. portunus infection. Elucidating the response characteristics of hemolymph and hepatopancreas to microsporidian infection facilitates the development of microsporidiosis prevention and control strategy. This study performed comparative transcriptomic analysis of hemolymph (PTX/PTXA) and hepatopancreas (PTG/PTGA) of P. trituberculatus uninfected and infected with A. portunus. The results showed that there were 223 and 1309 differentially expressed genes (DEGs) in PTX/PTXA and PTG/PTGA, respectively. The lysosome pathway was significantly enriched after the invasion of the hemolymph by A. portunus. Also, immune-related genes were all significantly up-regulated in the hemolymph and hepatopancreas, suggesting that the invasion by A. portunus may activate host immune responses. Unlike hemolymph, antioxidant and detoxification-related genes were also significantly up-regulated in the hepatopancreas. Moreover, metabolism-related genes were significantly down-regulated in the hepatopancreas, suggesting that energy synthesis, resistance to pathogens, and regulation of oxidative stress were suppressed in the hepatopancreas. Hemolymph and hepatopancreas have similarity and tissue specificity to microsporidian infection. The differential genes and pathways identified in this study can provide references for the prevention and control of microsporidiosis.


Assuntos
Braquiúros , Microsporídios , Microsporidiose , Animais , Braquiúros/genética , Hemolinfa , Hepatopâncreas/metabolismo , Microsporídios/genética , Microsporidiose/metabolismo , Transcriptoma
6.
Chem Commun (Camb) ; 60(1): 106-109, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38032358

RESUMO

Organophotocatalytic cascade cross-dehydrogenative-coupling/cyclization reaction of o-hydroxyarylenaminones with α-amino acid derivatives for the construction of α-chromone substituted α-amino acid derivatives was developed. Various N-arylglycine esters, amides and dipeptides underwent the cascade cyclization reaction well with o-hydroxyarylenaminones to afford the corresponding 3-aminoalkyl chromones in good to excellent yields. This approach consists of visible-light-promoted oxidation of α-amino acid derivatives, the Mannich reaction, and intramolecular nucleophilic cyclization under acidic conditions, and features a wide reaction scope, a simple operation and mild reaction conditions, which may have the potential to be used for the synthesis of bioactive molecules.

7.
Ann Ital Chir ; 94: 384-391, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794798

RESUMO

This study explored the value of the detection of serum methylated septin 9 (mSEPT9) and carcinoembryonic antigen (CEA) in the auxiliary diagnosis, curative effect evaluation, and follow-up monitoring of colorectal cancer (CRC). The diagnosis and treatment data of 208 CRC patients in the First Affiliated Hospital of Xinjiang Medical University (China) were collected from March 2019 to December 2019, and these patients were followed up. The correlation between serum CEA, mSEPT9 levels, and tumor location and size were analyzed. Serum mSEPT9 and CEA were detected before and after surgery and during follow-up after treatment to analyze the value of mSEPT9 in efficacy evaluation and follow-up monitoring. In 87 patients with CRC patients who underwent surgery, the average size of poorly differentiated tumors was the largest (25.01±14.08 cm2), which was significantly different from that of moderately differentiated tumors (P =0.039). There was a statistically significant difference in serum CEA level among different degrees of differentiation (P=0.018). The level of CEA was relatively low when tumors occurred in the transverse and ascending colon. When the level of CEA was high, negative mSEPT9 suggested that the probability of a tumor occurring in the cecum was high; positive mSEPT9 indicated that the tumor was highly likely to occur in the descending or sigmoid colon. Detection before and after surgery revealed that the level of mSEPT9 may be related to the tumor-bearing state of patients. A Follow-up study also showed that the sensitivity and specificity of mSEPT9 for recurrence and metastasis were 83.3% and 97.7%, respectively, and the sensitivity and specificity of CEA were 61.1% and 89.5%, respectively. The combined detection of mSEPT9 and CEA can indicate the location and size of colorectal cancer, while the detection of serum mSEPT9 may have clinical significance in the efficacy evaluation and follow-up monitoring of colorectal cancer. KEY WORDS: Colorectal Cancer, mSEPT9, Recurrence, Metastasis, CEA.


Assuntos
Antígeno Carcinoembrionário , Neoplasias Colorretais , Humanos , Septinas/metabolismo , Biomarcadores Tumorais , Seguimentos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia
8.
Sci Adv ; 9(24): eadg7754, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327329

RESUMO

Chiral ketones and their derivatives are useful synthetic intermediates for the synthesis of biologically active natural products and medicinally relevant molecules. Nevertheless, general and broadly applicable methods for enantioenriched acyclic α,α-disubstituted ketones, especially α,α-diarylketones, remain largely underdeveloped, owing to the easy racemization. Here, we report a visible light photoactivation and phosphoric acid-catalyzed alkyne-carbonyl metathesis/transfer hydrogenation one-pot reaction using arylalkyne, benzoquinone, and Hantzsch ester for the expeditious synthesis of α,α-diarylketones with excellent yields and enantioselectivities. In the reaction, three chemical bonds, including C═O, C─C, and C─H, are formed, providing a de novo synthesis reaction for chiral α,α-diarylketones. Moreover, this protocol provides a convenient and practical method to synthesize or modify complex bioactive molecules, including efficient routes to florylpicoxamid and BRL-15572 analogs. Computational mechanistic studies revealed that C-H/π interactions, π-π interaction, and the substituents of Hantzsch ester all play crucial roles in the stereocontrol of the reaction.


Assuntos
Ésteres , Cetonas , Estereoisomerismo , Cetonas/química , Catálise
9.
Org Lett ; 25(8): 1299-1304, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36808990

RESUMO

The unique reactivity of in situ generated propargylic para-quinone methides as a new type of five-carbon synthon has been discovered by a novel bismuth(III)-catalyzed tandem annulation reaction. This 1,8-addition/cyclization/rearrangement cyclization cascade reaction is characterized by unusual structural reconstruction of 2-vinylphenol, involving cleavage of the C1'═C2' bond and formation of four new bonds. This method provides a convenient and mild approach to generate synthetically important functionalized indeno[2,1-c]chromenes. The mechanism of the reaction is proposed from several control experiments.

12.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6492-6499, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38212006

RESUMO

Shenfu Injection(SFI) is praised for the high efficacy in the treatment of septic shock. However, the precise role of SFI in the treatment of sepsis-associated lung injury is not fully understood. This study investigated the protective effect of SFI on sepsis-associated lung injury by a clinical trial and an animal experiment focusing on the hypoxia-inducing factor-1α(HIF-1α)-mediated mitochondrial autophagy. For the clinical trial, 70 patients with sepsis-associated lung injury treated in the emergency intensive care unit of the First Affiliated Hospital of Zhengzhou University were included. The levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-α were measured on days 1 and 5 for every patient. Real-time quantitative polymerase chain reaction(RT-qPCR) was performed to determine the mRNA level of hypoxia inducible factor-1α(HIF-1α) in the peripheral blood mononuclear cells(PBMCs). For the animal experiment, 32 SPF-grade male C57BL/6J mice(5-6 weeks old) were randomized into 4 groups: sham group(n=6), SFI+sham group(n=10), SFI+cecal ligation and puncture(CLP) group(n=10), and CLP group(n=6). The body weight, body temperature, wet/dry weight(W/D) ratio of the lung tissue, and the pathological injury score of the lung tissue were recorded for each mouse. RT-qPCR and Western blot were conducted to determine the expression of HIF-1α, mitochondrial DNA(mt-DNA), and autophagy-related proteins in the lung tissue. The results of the clinical trial revealed that the SFI group had lowered levels of inflammatory markers in the blood and alveolar lavage fluid and elevated level of HIF-1α in the PBMCs. The mice in the SFI group showed recovered body temperature and body weight. lowered TNF-α level in the serum, and decreased W/D ratio of the lung tissue. SFI reduced the inflammatory exudation and improved the alveolar integrity in the lung tissue. Moreover, SFI down-regulated the mtDNA expression and up-regulated the protein levels of mitochondrial transcription factor A(mt-TFA), cytochrome c oxidase Ⅳ(COXⅣ), HIF-1α, and autophagy-related proteins in the lung tissue of the model mice. The findings confirmed that SFI could promote mitophagy to improve mitochondrial function by regulating the expression of HIF-1α.


Assuntos
Lesão Pulmonar Aguda , Medicamentos de Ervas Chinesas , Sepse , Humanos , Masculino , Camundongos , Animais , Leucócitos Mononucleares , Camundongos Endogâmicos C57BL , Pulmão/metabolismo , Lesão Pulmonar Aguda/tratamento farmacológico , Fator de Necrose Tumoral alfa/genética , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/genética , Hipóxia/patologia , Proteínas Relacionadas à Autofagia , Peso Corporal
13.
J Org Chem ; 87(21): 14965-14969, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36279475

RESUMO

Herein, we reported a practical and efficient strategy combining photoredox and enzyme catalysis for the construction of 3-aminoalkyl chromones from o-hydroxyaryl enaminones and N-arylglycine esters. A variety of 3-aminoalkyl chromones were synthesized with good yields under mild conditions in one pot. This synthetic protocol consists of sequential enzymatic hydrolysis and photoredox decarboxylation of N-arylglycine esters, oxidation of aminoalkyl radicals, Mannich reaction, and intramolecular nucleophilic cyclization, which affords a convenient pathway for the preparation of various 3-substituted chromones.


Assuntos
Cromonas , Ésteres , Catálise , Ciclização , Oxirredução
15.
ACS Appl Mater Interfaces ; 13(50): 60261-60268, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34874144

RESUMO

Stable and efficient emitters are highly desired for near-infrared organic light-emitting diodes (NIR OLEDs) due to their extensive applications in biometric authentication, night vision display, and telecommunication. As this technology advances, there is an increasing demand for the development of NIR OLEDs with an emission spectrum beyond 900 nm. This work reports a stable and efficient near-infrared Pt(II) porphyrin complex, i.e., Pt(II) tetra(3,5-difluorophenyl)tetranaphthoporphyrin named PtTPTNP-F8, of which 84% of the total emitted photons are at wavelengths longer than 900 nm. By introducing fluorine atoms on the meta positions of all four phenyl groups, PtTPTNP-F8 can successfully overcome the common thermal instability issue emerging from the heavy Pt(II) porphyrin complexes, demonstrating a sublimation yield of above 90%. By carefully choosing the host materials, a NIR OLED device with PtTPTNP-F8 as an emissive material achieves a high peak device efficiency of 1.9%. Furthermore, devices of PtTPTNP-F8 fabricated in a stable device structure demonstrate extraordinary operational stability with an LT99 lifetime (time to 99% of the initial photocurrent) of more than 1000 h at a constant driving current density of 20 mA cm-2.

16.
J Org Chem ; 86(23): 16518-16534, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34714074

RESUMO

Dearomatization of indole is a useful strategy to access indolimines: a motif widely exists in biologically active molecules and natural products. Herein, an efficient method for the dearomatization of 2,3-disubstituted indoles to generate diverse indolimines with tetrasubstituted allenes is described. This work accomplishes dearomatization of 2,3-disubstituted indoles through 1,8-addition of (aza)-para-quinone methides, which are generated in situ from propargylic alcohols. A series of synthetically useful indolimines containing quaternary carbon centers and tetrasubstituted allenes can be accessed in good yields (up to 99%). Additionally, the separability of product isomers, diversified product transformations, and easy scale-up of the reaction demonstrate the potential application of this method.


Assuntos
Indolquinonas , Indóis
17.
Adv Mater ; 33(33): e2101423, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34245184

RESUMO

Phosphorescent molecular aggregates show promise in realizing efficient and stable organic light-emitting diodes (OLEDs) operating at high brightness level, which is highly desired for future lighting and display applications. Herein, four tetradentate Pd(II) complexes are prepared with judicious ligand design, and their electrochemical and photophysical properties are thoroughly examined. The studies indicate that slight structural changes of ligands can modify the hole and electron transporting capabilities, and alter the horizontal emitting dipole ratios of aggregates in amorphous film, the latter of which are sensitive to the thin-film deposition conditions including the deposition rate and the choice of the templating layer. An optimized OLED device using Pd3O8-Py5 aggregates exhibits a peak external quantum efficiency (EQE) of 37.3% and a reduced efficiency roll-off with high EQEs of 36.0% and 32.5% at 1000 and 10 000 cd m-2 , respectively. Moreover, such an efficient device demonstrates a long measured LT95 (time to 95% of the initial luminance) lifetime of over 500 h with an initial brightness of 17 304 cd m-2 corresponding to an estimated LT95 lifetime of 48 246 h at 1000 cd m-2 .

18.
J Org Chem ; 86(11): 7490-7499, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34004118

RESUMO

A novel Brønsted acid catalyzed 1,8-addition mediated (3 + 4)-annulation of in situ generated propargylic p-quinone methides with 2-indolylmethanols is described. This method provides a convenient and mild approach to structurally interesting and synthetically important polysubstituted indole-fused oxepines in high yields. Moreover, 2-indolylmethanols as four-atom synthons in the (3 + 4)-annulations under Brønsted acid conditions have been explored for the first time.


Assuntos
Indolquinonas , Indóis
19.
Org Biomol Chem ; 19(7): 1616-1619, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33533370

RESUMO

A novel and straightforward intramolecular cyclization of glycine derivatives to 2-substituted benzoxazoles through copper-catalyzed oxidative C-H/O-H cross-coupling was described. A variety of glycine derivatives involving short peptides underwent cross-dehydrogenative-coupling readily to afford diverse 2-substituted benzoxazoles. The synthetic method has the advantages of simple operation, broad substrate scope and mild reaction conditions, thus providing an alternative effective approach for benzoxazole construction.

20.
Food Chem Toxicol ; 150: 112069, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33607219

RESUMO

Lately, long non-coding RNA (lncRNA) is recognized as a key regulator of gastric cancer (GC) which has aroused great interest in the fields of medicine, toxicology, and functional food. Studies related to LncRNA expression microarray data indicate that BX357664 is down-regulated in GC specimens. However, the expression pattern and molecular mechanism of BX357664 in GC have not been studied so far. The purpose of this study was to investigate the expression of lncRNA BX357664 in GC and its function in GC cell lines. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the level of BX357664 in 50 pairs of cancer tissues and adjacent non-cancer tissues collected from GC patients. It was found that BX357664 level was lowered in cancer specimens than adjacent non-cancer tissues and correlated with tumor size and TNM stage. Also, we used cell counting kit 8 (CCK8), cell clone formation assay and transwell assay, which affirmed that up-regulation of BX357664 inhibited the proliferation, migration, and invasion of GC cells, but promoted apoptosis. In the dual-luciferase report analysis, BX357664 acted as a miR-183-3p ceRNA to target and regulate the expression of PTEN and affect the PI3K/AKT pathway. These results indicate that BX357664 can inhibit the proliferation and metastasis of GC through the miR-183-3p/PTEN/PI3K/AKT pathway, which may serve as potential targets for the treatment of GC in the future.


Assuntos
Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Células Epiteliais , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Neoplasias Experimentais , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Longo não Codificante , Neoplasias Gástricas
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