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1.
Chemistry ; : e202402974, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145542

RESUMO

Herein, a microwave promoted tandem reaction of free primary arylamines with diazo compounds in water for clean synthesis of 2,2-disubstituted 3-oxindoles is present. Water plays important roles in the whole cascade process: O-H insertion to diazo, air oxidation, ortho C-H functionalization, cyclization and 1,2-ester migration. In particular, water plays a mediation role in the site selective ortho-C-H addition.

2.
Nat Commun ; 15(1): 6183, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39039050

RESUMO

The de novo construction of enantioenriched 3-hydroxyindolenines and 3-oxindoles from easily available starting materials has been highly desired. Herein, an enantioselectively intermolecular direct [3 + 2] annulation of aryl amine with 2,3-diketoesters to construct 3-hydroxyindolenines with a chiral tertiary alcohol has been disclosed. The results of control experiments and DFT calculation revealed that π - π interaction plays a pivotal role in the enantioselectivity-determining process of [3 + 2] annulation. The following unusual concerted [1,2]-ester migration provides a family of chiral 3-oxindoles in good to excellent yields with excellent enantioselectivity.

3.
J Org Chem ; 89(15): 10678-10683, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39013075

RESUMO

A radical cascade cyclization of 2-alkynylaniline derivatives with sulfonyl chlorides was developed to construct C3-sulfone methylene-substituted indolines in yields of 21 to 85% with a broad substrate scope under metal- and base-free conditions. This protocol could simultaneously build three new chemical bonds and employ a solvent-radical relay strategy, providing a rapid and concise approach toward an indoline framework. Scale-up reactions of this method and further transformations to afford useful indolines were also demonstrated.

4.
J Hazard Mater ; 477: 135236, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39038377

RESUMO

Collaborative treatment of pollutants is a promising approach for wastewater treatment. In this work, a covalent organic framework material (COFs) with an imine structure was synthesised by the Schiff base reaction, and photochemical tests showed good photochemical effects. It was used to explore the photocatalytic treatment of co-existing pollutants (heavy metal ions and antibiotics) and the performance of treating co-existing wastewater was investigated. The degradation performance of levofloxacin (LVX) and Cr(VI) was improved in the coexisting pollutants system, with the LVX degradation being 4.2 times more effective than that of the LVX solitary system. Moreover, this phenomenon was also observed in LVX/Ag(I), LVX/Fe(III), sulfadiazine/Cr(VI), norfloxacin/Cr(VI) and tetracycline/Cr(VI) systems. The analysis of active species suggesting that the synergistic promotion of photocatalytic oxidation-reduction systems was not only promoting from the improvement of simple charge separation, but it was also found that high-valent metal species can act directly in the oxidative decomposition of antibiotics. The interaction of pollutants and intermediates were rationally exploited and confirmed by control experiments and theoretical calculation. This conclusion helps us to re-examine the underlying mechanisms of photocatalytic synchronous oxidation and reduction reactions, simultaneously beneficial for the development of mixed pollutant control processes.

5.
Chinese Journal of School Health ; (12): 244-247, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1012513

RESUMO

Objective@#To explore the latent categories and general demographic characteristics of short form video addiction among college students, so as to provide empirical reference for prevention and intervention of short form video addiction among college students.@*Methods@#Convenience sampling method was used to select 1 386 college students from a certain university in Anhui Province in June 2023. A questionnaire survey was conducted among college students by using the Short Video Addiction Scale. The latent profile analysis method of "individual center" was used to explore the categories of college students short form video addiction, and multiple Logistic regression was used to explore the influence of demographic variables on the latent classification of short form video addiction.@*Results@#College students with short form video addiction were divided into three latent categories:non addiction group (22.15%, n =307), low addiction group (63.28%, n =877) and high addiction group (14.57%, n =202). The results of multiple Logistic regression analysis showed that gender, major type and family location were related with short form video addiction among college students:male students (low addiction group: OR =0.47; high addiction group: OR =0.41), cultural and historical majors (low addiction group: OR =0.66), and students from cities (high addiction group: OR =0.51) were less likely to be involved in short form video addiction ( P <0.05).@*Conclusions@#There is significant group heterogeneity in short form video addiction among college students. Families, schools and society should attach importance and pay attention to the phenomenon of short form video addiction among college students, actively take targeted intervention measures to prevent and reduce the occurrence of short form video addiction symptoms among college students.

6.
J Org Chem ; 88(21): 15249-15255, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37862612

RESUMO

ß-Lactam is a ubiquitous scaffold in bioactive compounds and pharmaceuticals. Herein, we disclose a streamlined method for the construction of ß-lactams starting from unactivated alkenes and alkyl bromides via a Cu-catalyzed inter-/intramolecular carboamidation. This reaction proceeded smoothly under mild reaction conditions and exhibited a broad substrate scope and various functional groups. This protocol is not only compatible with 1, 2, and 3° alkyl bromides but also suitable for α-bromo nitrile as well as various benzyl bromides. The mechanism exploration indicated that sequential radical addition/reductive elimination was involved.

7.
Org Biomol Chem ; 21(27): 5616-5621, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37376991

RESUMO

A simple and efficient one-pot intermolecular annulation reaction for the synthesis of 1,2,4-oxadiazoles from amidoximes and benzyl thiols has been developed, in which benzyl thiols act as not only reactants but also organo-catalysts. The control experiments proved that thiol substrates could facilitate the dehydroaromatization step. High yield, functional group diversity and transition metal-free, extra oxidant-free, and mild conditions are the important practical features. Moreover, this protocol provides an effective alternative method for the synthesis of a commercially available broad-spectrum nematicide, tioxazafen.

8.
Org Lett ; 25(15): 2582-2587, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37036149

RESUMO

Transition metal-controlled divergent annulation reactions of azomethine imines with iodonium ylides via C-centered [1,2]-rearrangement have been developed. The azomethine imino group, as a switchable and transient directing group (DG), underwent intramolecular nucleophilic addition and in situ generated bicyclic diaziridine, which facilitated the C-centered [1,2]-rearrangement and subsequent divergent annulations in the presence of different metal complexes as the catalysts. The benzo[c]chromen-1-one and pyrano[de]isochromene scaffolds could be independently constructed with Rh(III) and Ru(II), respectively. It was worth noting that the azomethine imino group was employed first as the switchable DG through rearrangement progress.

9.
Org Lett ; 25(16): 2782-2787, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37061941

RESUMO

An expeditious copper-catalyzed three-component hydroxyperfluoroalkylation of unactivated alkenes starting from commercially available perfluoroalkyl iodides and an O2 molecule from air as the oxygen source was developed. The Cu/B2pin2 catalytic system offered a novel pattern for the generation of perfluoroalkyl radicals and overcame the previous limitations in the hydroxyperfluoroalkylation of unactivated alkenes. This catalytic protocol features high regioselectivity and broad substrate scope to access valuable ß-perfluoroalkyl alcohols expediently. 18O-labeling experiments demonstrated that the oxygen atom of the OH group stems from O2 in air.

10.
Org Lett ; 25(17): 2953-2957, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087759

RESUMO

Described herein is the development of an unprecedented approach to construct multiple heterocycles with high selectivity through Rh(III)-catalyzed two- or three-component cyclization reaction from simple and readily available starting materials: N-methoxybenzamides, 2-butyne biscarbonate, and maleimides. This methodology provides an efficient strategy for the synthesis of diverse and complicated heterocycles in a one-pot manner and displays excellent features of extremely mild reaction conditions, easy operation, excellent regioselectivity, and good functional group compatibility.

11.
ACS Omega ; 8(8): 7517-7528, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36872989

RESUMO

A highly efficient method for synthesis of difluoroarymethyl-substituted benzimidazo[2,1-a]isoquinolin-6(5H)-ones using 2-arylbenzoimidazoles with α,α-difluorophenylacetic acid as reaction substrates has been developed through radical cascade cyclization. The advantage of this strategy lies in excellent functional group tolerance to generate the corresponding products in good yields under base- and metal-free conditions.

12.
Chemistry ; 29(25): e202300301, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36757635

RESUMO

TBAI-catalysed [4+4]-cyclization reaction of anthranils with hydrazones to deliver oxa-bridged eight-membered heterocycles in accepted yields was developed. Preliminary mechanistic studies indicated that the reaction involved the in situ generation of vinyldiazenes from readily available hydrazones followed by an aza-Michael addition of the anthranil substrates onto the vinyldiazenes and subsequent annulation. This transformation involved the formation of two new C-N bonds and C-O bond in one pot, overcoming the synthetic limitations of anthranils in organic chemistry. This strategy benefits from high efficiency and atomic economy with mild reaction conditions.

13.
Anticancer Drugs ; 34(1): 135-143, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539366

RESUMO

Nasopharyngeal carcinoma (NPC) is one of the most frequent malignant tumors diagnosed in China. Cisplatin is one of the most commonly used anticancer drugs containing platinum in combined chemotherapy. The molecular mechanism of NPC is still largely unknown, and we aim to spare no effort to elucidate it. Normal human nasopharyngeal epithelial cells and NPC cell lines were cultured. The expression levels of miR-302c-5p and HSP90AA1 were detected with quantitative real-time PCR. Western blotting was used to analyze levels of the HSP90AA1, protein kinase B (AKT), p-AKT, CD44 and SOX2 proteins. The interaction between miR-302c-5p and HSP90AA1 was detected using a luciferase reporter assay. The bicinchoninic acid assay was used to observe cisplatin resistance in NPC cells. Our records confirmed that the expression of miR-302c-5p was substantially reduced and HSP90AA1 was increased in NPC cells. Additionally, miR-302c-5p inhibited cisplatin resistance and the traits of stem cells in NPC. A luciferase assay confirmed that miR-302c-5p is bound to HSP90AA1. Overexpression of HSP90AA1 may reverse the effects of overexpressed miR-302c-5p and inhibit cisplatin resistance and stem cell traits of NPC. This study investigated whether miR-302c-5p inhibited the AKT pathway by regulating HSP90AA1 expression and altered the resistance of NPC cells to cisplatin and the traits of tumor stem cells, which has not yet been reported.


Assuntos
MicroRNAs , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Cisplatino/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP90/metabolismo
14.
J Org Chem ; 87(21): 14364-14373, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36285822

RESUMO

A facile and mild Ru(II)-catalyzed ortho-C-H hydroxyfluoroalkylation of arenes with cheap and easily accessible fluorinated alcohols has been developed in the presence of 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO). The readily available fluorinated alcohols were used as hydroxyfluoroalkylation reagents to form various α-aryl-α-trifluoromethyl alcohols. The present work provides a new method for the introduction of hydroxyfluoroalkyl groups into arenes.

15.
Org Lett ; 24(41): 7502-7506, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36218222

RESUMO

A highly regioselective synthesis of spiro[benzofuran-2,2'-furan]-3-ones has been explored via Lewis acid-catalyzed [3 + 2] cyclization of iodonium ylides with azadienes. The acidity of the Lewis acid was significantly strengthened with strong hydrogen bond donors, thereby promoting the enolization isomerization of iodonium ylides for the subsequent cycloaddition. This reaction was compatible with a broad range of substrates under the mild reaction conditions, and efficiently delivered spiro-heterocycles with excellent stereoselectivity.

16.
Org Biomol Chem ; 20(34): 6750-6754, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35938985

RESUMO

An original and facile method for the generation of ß-naphtha-1-thioquinones using DAST and 2-naphthols has been developed. A series of dehydro-2-naphthol-1-sulphides or naphtha-oxathiane derivatives were synthesized by in situ Diels-Alder cycloaddition reactions of ß-naphtha-1-thioquinone with itself or various alkenes.


Assuntos
Naftóis , Alcanos , Reação de Cicloadição , Dietilaminas , Flúor , Solventes , Estereoisomerismo
17.
Org Biomol Chem ; 20(32): 6459-6463, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35894817

RESUMO

A mild and efficient visible-light-induced radical method was developed to produce C3-malonated five-membered heterocycles using 2-substituted thiophenes/furans and diethyl bromomalonate as the starting materials. Various 2-substituted (benzo)thiophenes/furans were suitable for the C3-ethoxycarbonylmethylation. The free radical mechanism was proposed based on the results of control experiments, cyclic voltammetry experiments and luminescence quenching experiments. We suggested that the heteroleptic halogen-bridged iridium(III) dimers might play an important role in this system.


Assuntos
Furanos , Tiofenos , Luz , Estrutura Molecular
18.
Chem Commun (Camb) ; 58(62): 8674-8677, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35822922

RESUMO

A mild and efficient Cu-assisted trifluoromethylthiolation/radical cascade cyclization of alkynes with readily available and stable AgSCF3 as the trifluoromethylthiolating reagent has been disclosed. This transformation provides an opportunity to construct a series of potential medicinally valuable trifluoromethylthio-substituted dioxodibenzothiazepines with wide functional group compatibility. This protocol opens up a new avenue for the construction of useful trifluoromethylthiolated seven-membered N-heterocycles.


Assuntos
Alcinos , Cobre , Catálise , Ciclização , Indicadores e Reagentes
19.
Cell Mol Life Sci ; 79(7): 357, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680727

RESUMO

BACKGROUND: Radiation is currently used to be a mainstay of salvage therapy for nasopharyngeal carcinoma (NPC), however, development of radioresistance largely limits the radiation efficacy. Circular RNAs (circRNAs) have been shown to affect NPC progression, but its role in radioresistance remain unclear. METHODS: The circular structure of circFIP1L1(circ_0069740) was verified by RNA-sequencing, RT-PCR based on gDNA or cDNA, RNase R treatment, and actinomycin D treatment. Cellular localization of circFIP1L1 and miR-1253 was detected by nucleoplasmic separation and/or fluorescence in situ hybridization. Expression of non-coding RNAs and mRNAs was detected by qRT-PCR, protein expression was detected by Western blot. Functionally, EdU, CCK-8, and colony formation experiments were employed to assess cell proliferation, flow cytometry was adopted to estimate cell cycle and apoptosis. Xenograft tumor growth was performed to detect the role of circFIP1L1 in vivo. Mechanistically, we examined the interplay between miR-1253 and circFIP1L1 or EIF4A3 through dual-luciferase reporter assay. The potential regulatory impacts of EIF4A3 on circFIP1L1 or PTEN was examined by RNA immunoprecipitation and RNA pull-down assays. RESULTS: CircFIP1L1 overexpression and miR-1253 knockdown repressed NPC cell proliferation, facilitated NPC cell apoptosis, and enhanced NPC radiosensitivity. Mechanistically, circFIP1L1 was revealed to repress miR-1253 by binding to it, and EIF4A3 is a target gene of miR-1253. CircFIP1L1 regulated NPC proliferation, apoptosis, and radiosensitivity through miR-1253/EIF4A3. Moreover, we found that EIF4A3 bound to FIP1L1 mRNA transcript and induced circFIP1L1 formation, and thus stabilizing PTEN mRNA. CONCLUSION: Our findings suggested that EIF4A3-induced circFIP1L1 repressed NPC cell proliferation, facilitated NPC cell apoptosis, and enhanced NPC radiosensitivity by miR-1253.


Assuntos
MicroRNAs , Neoplasias Nasofaríngeas , Linhagem Celular Tumoral , Proliferação de Células/genética , RNA Helicases DEAD-box/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/radioterapia , RNA Mensageiro , Tolerância a Radiação/genética
20.
Org Lett ; 24(25): 4650-4655, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704765

RESUMO

Dioxazolone has been attractive as an important synthon for a direct C-H amidation through a nitrene intermediate or Curtius rearrangement to form the isocyanate. However, the combination of two reaction models of dioxazolone has not been reported. Herein, a cobalt-catalyzed C-H and N-H functionalization of 1-arylpyrazolidinones with dioxazolones was developed. The dioxazolones acted as an amidated and carboxamidated reagent. Three C-N bonds were formed in a "one-pot" manner, which promoted the requirement of synthetic diversity.

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