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1.
Org Biomol Chem ; 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39420589

RESUMEN

A mild, scalable, and high-yielding visible-light-promoted C-S cross-coupling between alkyl thiol derivatives and (hetero)aryl halides without the need for metals, ligands, or photocatalysts is reported, offering advantages over traditional C-S bond forming strategies. The formation of an electron donor-acceptor (EDA) complex is supported by experimental and computational mechanistic studies, which undergoes visible-light-induced charge transfer to initiate C-S bond formation in the absence of a photoredox catalyst.

3.
Org Lett ; 26(40): 8636-8642, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39326000

RESUMEN

A chlorotrimethylsilane (TMSCl)-mediated cascade phosphorylation and cycloisomerization of enynones with diphenylphosphine oxides is presented. This methodology enables the highly selective synthesis of monophosphorylated 2H-pyrans and bisphosphorylated dihydropyrans through precise solvent-reagent stoichiometry control. The strategy demonstrated excellent functional group compatibility and high yields (up to 96%), providing facile access to structurally diverse phosphorylated heterocycles with potential applications in medicinal chemistry and materials science.

4.
Org Lett ; 26(39): 8289-8294, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39315995

RESUMEN

Multicomponent radical tandem reactions have emerged as a crucial technique for synthesizing complex molecules in organic chemistry. In this study, we report a palladium-catalyzed four-component difluoroalkylative carbonylation of enynes and ethyl difluoroiodoacetate. This transformation proceeds through a multistep sequential reaction that introduces reactive difluoro and carbonyl groups while constructing the benzofuran skeleton. Moreover, a variety of valuable 2,3-disubstituted benzofuran derivatives were obtained in respectable yields with excellent functional group compatibility.

5.
Org Lett ; 26(37): 7834-7840, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39235769

RESUMEN

The Narasaka-Heck reaction is one of the most straightforward methods for constructing pyrroline derivatives. Herein, we report a novel nickel-catalyzed three-component carbonylation reaction, which cleverly realizes the continuous construction of C(sp3)-N bonds and C(sp3)-C(sp2) bonds and effectively promotes the synthesis of acyl-substituted pyrroline derivatives. Furthermore, this strategy not only expands the conversion pathway of γ,δ-unsaturated oxime esters but also provides a new method for the synthesis of nitrogen-containing heterocyclic compounds.

6.
BMC Microbiol ; 24(1): 237, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961326

RESUMEN

OBJECTIVE: Bladder cancer(BCa) was a disease that seriously affects patients' quality of life and prognosis. To address this issue, many researches suggested that the gut microbiota modulated tumor response to treatment; however, this had not been well-characterized in bladder cancer. In this study, our objective was to determine whether the diversity and composition of the gut microbiota or the density of specific bacterial genera influence the prognosis of patients with bladder cancer. METHODS: We collected fecal samples from a total of 50 bladder cancer patients and 22 matched non-cancer individuals for 16S rDNA sequencing to investigate the distribution of Parabacteroides in these two groups. Further we conducted follow-up with cancer patients to access the impact of different genera of microorganisms on patients survival. We conducted a Fecal Microbiota Transplantation (FMT) and mono-colonization experiment with Parabacteroides distasonis to explore its potential enhancement of the efficacy of anti-PD-1 immunotherapy in MB49 tumor-bearing mice. Immunohistochemistry, transcriptomics and molecular experiment analyses were employed to uncover the underlying mechanisms. RESULTS: The 16S rDNA showed that abundance of the genus Parabacteroides was elevated in the non-cancer control group compared to bladder cancer group. The results of tumor growth curves showed that a combination therapy of P. distasonis and ICIs treatment significantly delayed tumor growth and increased the intratumoral densities of both CD4+T and CD8+T cells. The results of transcriptome analysis demonstrated that the pathways associated with antitumoral immune response were remarkably upregulated in the P. distasonis gavage group. CONCLUSION: P. distasonis delivery combined with α-PD-1 mAb could be a new strategy to enhance the effect of anti-PD-1 immunotherapy. This effect might be achieved by activating immune and antitumor related pathways.


Asunto(s)
Bacteroidetes , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Inmunoterapia , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/microbiología , Animales , Humanos , Ratones , Inmunoterapia/métodos , Bacteroidetes/genética , Bacteroidetes/inmunología , Femenino , Masculino , ARN Ribosómico 16S/genética , Heces/microbiología , Persona de Mediana Edad , Anciano , Ratones Endogámicos C57BL
7.
Org Biomol Chem ; 22(38): 7834-7840, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39037724

RESUMEN

Organic synthesis methods initiated by visible light have received increasing attention from synthetic chemists. Reactions initiated by EDA complexes do not require the use of toxic or expensive photoredox catalysts, unlike traditional photoreaction processes. However, this kind of reaction requires a particular structure for the substrate, so it is important to study the detailed and systematic reaction mechanism for its design. EDA complexes of substituted 1H-indole and substituted benzyl bromide derivatives were studied by density functional theory (DFT). The difference between EDA complexes with substituents of different kinds and locations were compared by theoretical study and a new EDA complex was predicted.

8.
J Org Chem ; 89(11): 7741-7746, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38741558

RESUMEN

A novel three-component cyclization carbonylation reaction of iodoarene-tethered propargyl ethers with amine and CO is reported. This palladium-catalyzed cascade reaction undergoes a sequence of oxidative addition, unsaturated bond migration, carbonyl insertion, and nucleophilic attack to deliver the benzofuran skeleton. Both aromatic amines and aliphatic amines could proceed smoothly in this transformation under one atm of CO.

9.
J Phys Condens Matter ; 36(30)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38588675

RESUMEN

Modulating interlayer coupling modes can effectively enhance the thermoelectric properties of nanomaterials or nanoscale devices. By using density functional theory combined with non-equilibrium Green's function method, we investigate the thermoelectric properties of zigzag-type black arsenic nanoscale devices with varying interlayer coupling modes. Our results show that altering the interlayer coupling mode significantly modulates the thermoelectric properties of the system. Specifically, we consider four coupling modes with different strengths, by modulating different interlayer overlap patterns. Notably, in the weaker interlayer coupling mode, the system exhibits enhanced thermoelectric properties due to increased interface phonon scattering, for example, the M4reaching a peak value of 2.23 atµ= -0.73 eV. Furthermore, we explore the temperature-dependent behavior of each coupling model. The results suggest that the thermoelectric characteristics are more sensitive to temperature variations in the weaker coupling modes. These insights provide valuable guidance for enhancing the thermoelectric performance of nanoscale devices through precise interlayer coupling modulation.

10.
Cell Host Microbe ; 32(1): 48-62.e9, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38056458

RESUMEN

Acetaminophen overuse is a common cause of acute liver failure (ALF). During ALF, toxins are metabolized by enzymes such as CYP2E1 and transformed into reactive species, leading to oxidative damage and liver failure. Here, we found that oral magnesium (Mg) alleviated acetaminophen-induced ALF through metabolic changes in gut microbiota that inhibit CYP2E1. The gut microbiota from Mg-supplemented humans prevented acetaminophen-induced ALF in mice. Mg exposure modulated Bifidobacterium metabolism and enriched indole-3-carboxylic acid (I3C) levels. Formate C-acetyltransferase (pflB) was identified as a key Bifidobacterium enzyme involved in I3C generation. Accordingly, a Bifidobacterium pflB knockout showed diminished I3C generation and reduced the beneficial effects of Mg. Conversely, treatment with I3C or an engineered bacteria overexpressing Bifidobacterium pflB protected against ALF. Mechanistically, I3C bound and inactivated CYP2E1, thus suppressing formation of harmful reactive intermediates and diminishing hepatocyte oxidative damage. These findings highlight how interactions between Mg and gut microbiota may help combat ALF.


Asunto(s)
Acetaminofén , Fallo Hepático Agudo , Humanos , Ratones , Animales , Acetaminofén/efectos adversos , Acetaminofén/metabolismo , Magnesio/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Citocromo P-450 CYP2E1/farmacología , Hígado/metabolismo , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/metabolismo
11.
J Affect Disord ; 346: 135-143, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-37949242

RESUMEN

BACKGROUND: To determine the prevalence of depression and anxiety among older adults in China, and explore the associated factors. METHODS: This cross-sectional study recruited participants between October 2022 and December 2022. The sample collection utilized a multi-stage stratified equal probability random sampling method. This study included 8436 older adults who underwent interviews utilizing standardized assessment instruments. The assessment of depressive symptoms employed the Patient Health Questionnaire 9, while the evaluation of anxiety utilized the Generalized Anxiety Disorder 7. Multivariate logistic regression was conducted to determine the odds ratio and 95 % confidence interval (CI). RESULTS: The weighted prevalence rates for depression and anxiety were 2.79 % (95 % CI: 2.38 %-3.28 %) and 1.39 % (95 % CI: 1.12 %-1.74 %), respectively. Older adults who were female, widowed, had irregular dietary habits, spent <1 h per day using electronic devices for socializing and entertainment, engaged in >8 h of sedentary behavior per day, and had chronic diseases (cardiovascular disease, cerebrovascular disease, insomnia, and Chronic gastroenteritis) displayed a higher likelihood of encountering symptoms indicative of depression and anxiety. Conversely, older adults living in rural areas and those who walked daily were less prone to experience symptoms of depression and anxiety. CONCLUSIONS: This study suggests that the psychological well-being of older adults should be cared for when treating chronic diseases. Moreover, families, communities, and clinics should recognize that supporting regular diets, providing social engagement and recreational activities, encouraging physical activity, and minimizing sedentary behavior can reduce the risk of depression and anxiety.


Asunto(s)
Ansiedad , Depresión , Humanos , Femenino , Anciano , Masculino , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Prevalencia , Ansiedad/epidemiología , Ansiedad/psicología , Trastornos de Ansiedad/epidemiología , Enfermedad Crónica , China/epidemiología
13.
Phys Chem Chem Phys ; 25(40): 27448-27456, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37796158

RESUMEN

Interface design and energy band engineering are two key strategies for improving the thermoelectric conversion efficiency of low dimensional nanoscale devices. By using first-principle-based density functional theory combined with a non-equilibrium Green function method, the thermoelectric properties of a single tetrathiafulvalene (TTF) molecule coupled with armchair phosphorene nanoribbons (APNRs) within different interface modes have been investigated. The results indicate that phonon transport can be dramatically suppressed in this intermediate weak-coupling system due to strong interfacial phonon scattering behavior, where very few phonons can propagate through two nonbonded interface regions from left side lead to a TTF molecule and then to right side lead. Furthermore, connecting a thiophene group at both the head and tail of the intermediate TTF molecule can significantly enhance the power factor (S2σ) of such a weak-coupling system based on an out-of-plane electronic transmission mechanism, and there is obvious charge transfer from S atoms to upper and lower APNRs. Compared to a single regular method, composite interface co-design can achieve more accurate control of thermal/electrical transmission performance. Electrical conductance can be effectively improved with low phonon thermal conductance being maintained at the same time, and an excellent thermoelectric figure of merit (ZT) of 0.73 has been obtained near 0.6 eV.

14.
Org Biomol Chem ; 21(43): 8744-8748, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37873567

RESUMEN

A p-TsOH/halotrimethylsilane facilitated cycloketonization of γ-hydroxyl ynones is detailed. This methodology enables the one-step synthesis of polysubstituted 3(2H)-furanone products. It is remarkable that the reaction exhibits excellent regio- and chemoselectivity by the addition of very small quantities of p-toluenesulfonic acid and water.

15.
J Glob Antimicrob Resist ; 35: 268-270, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37866682

RESUMEN

OBJECTIVES: Prevotella bivia is a species that commonly colonizes various human body sites, and it is associated with lots of human infections. However, until now, no complete genome sequence of this species has been published. Here, we assembled the first complete genome of P. bivia from a clinically derived strain PLW0727, to characterize its general genomic features, and to profile the capacity in encoding antibiotic resistance and virulence factors. METHODS: Whole-genome sequencing was performed using Illumina and Nanopore platforms. Hybrid assembly was conducted using flye v2.9.1 and Unicycler v0.4.9b. Assembly completeness was assessed using CheckM v1.0.12. Comprehensive genome annotation was performed using eggNOG-mapper v2.1.5 and PATRIC v3.6.10. RESULTS: The complete genome of PLW0727 consists of two circular chromosomes, chr1 and chr2, exhibiting a completeness of 99.66%, a G+C content of 39.5%, and a total size of 2.43 Mb. Chr1 and chr2 have lengths of 1 272 652 bp and 1 155 021 bp, harbouring 1 132 CDSs and 1 055 CDSs, respectively. Completion of the genome significantly reduced the proportion of hypothetical CDS annotations compared with the draft genomes. A gene-encoding antibiotic resistance to beta-lactams (i.e., cfxA3) has been annotated in chr2. By providing the genome sequence, strain PLW0727 was identified as a human pathogen with a probability of 0.614 using the PathogenFinder. Furthermore, genes involved in virulence-related functions, including host cell adherence and capsule immune modulation were also annotated. CONCLUSIONS: This study assembles the first complete genome for P. bivia, providing valuable genomic insights into its phylogeny, pathogenicity, and antibiotic resistance. These findings have important implications for the clinical management and prevention of P. bivia infections.


Asunto(s)
Genoma Bacteriano , Prevotella , Humanos , Prevotella/genética , Secuenciación Completa del Genoma , Genómica
16.
Front Microbiol ; 14: 1147469, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37152761

RESUMEN

Background: Winkia neuii, previously known as Actinomyces neuii, is increasingly recognized as a causative agent of various human infections, while its taxonomy and genomic insights are still understudied. Methods: A Winkia strain NY0527 was isolated from the hip abscess of a patient, and its antibiotic susceptibility was assessed. The genome was hybrid assembled from long-reads and short-reads sequencing. Whole-genome-based analyses on taxa assignment, strain diversity, and pathogenesis were conducted. Results: The strain was found to be highly susceptible to beta-lactam antibiotics, but resistant to erythromycin, clindamycin, and amikacin. The complete genome sequences of this strain were assembled and found to consist of a circular chromosome and a circular plasmid. Sequence alignment to the NCBI-nt database revealed that the plasmid had high sequence identity (>90%) to four Corynebacterium plasmids, with 40-50% query sequence coverage. Furthermore, the plasmid was discovered to possibly originate from the sequence recombination events of two Corynebacterium plasmid families. Phylogenomic tree and genomic average nucleotide identity analyses indicated that many Winkia sp. strains were still erroneously assigned as Actinomyces sp. strains, and the documented subspecies within W. neuii should be reclassified as two separate species (i.e., W. neuii and W. anitratus). The core genome of each species carried a chromosome-coded beta-lactamase expression repressor gene, which may account for their broadly observed susceptibility to beta-lactam antibiotics in clinical settings. Additionally, an ermX gene that expresses fluoroquinolone resistance was shared by some W. neuii and W. anitratus strains, possibly acquired by IS6 transposase-directed gene transfer events. In contrast, tetracycline resistance genes were exclusively carried by W. neuii strains. In particular, W. neuii was found to be more pathogenic than W. anitratus by encoding more virulence factors (i.e., 35-38 in W. neuii vs 27-31 in W. anitratus). Moreover, both species encoded two core pathogenic virulence factors, namely hemolysin and sialidase, which may facilitate their infections by expressing poreformation, adhesion, and immunoglobulin deglycosylation activities. Conclusion: This study highlights the underappreciated taxonomic diversity of Winkia spp. and provides populational genomic insights into their antibiotic susceptibility and pathogenesis for the first time, which could be helpful in the clinical diagnosis and treatment of Winkia spp. infections.

17.
Org Lett ; 25(16): 2761-2766, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37052909

RESUMEN

We report a highly regioselective three-component coupling reaction of styrene, CO gas, and an amine compound to synthesize multisubstituted α,ß-unsaturated amides, which involves a palladium-catalyzed sequential 1,4-palladium migration, C(sp2)-H activation, carbonylation, and amination. Salient features of this strategy include the use of 1 atm of CO, excellent stereochemistry, and good functional group tolerance. Further, a series of control experiments and density functional theory calculations were performed to afford some insights for the transfer mechanism.

18.
Org Lett ; 25(13): 2306-2311, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36988237

RESUMEN

A novel and efficient method for the catalytic installation of a carbonyl group via remote radical coupling is disclosed. The nickel-catalyzed reaction proceeds to undergo a sequential single-electron transfer, 1,5-hydrogen atom transfer, and carbonyl insertion, thus providing the α-substituted ketone. Further, this reaction could be carried out smoothly under normal pressure and redox-neutral conditions, and demonstrated functional-group compatibility and excellent site-selectivity.

19.
J Org Chem ; 88(3): 1403-1410, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36656018

RESUMEN

A nickel-catalyzed three-component tandem radical cyclization reaction of aryl bromides with 1,3-enynes and aryl boric acids to construct γ-lactam-substituted allene derivatives has been described. This protocol provides lactam alkyl radicals through the free radical cyclization process, which can be effectively used to participate in the subsequent multicomponent coupling reaction so that 1,3-enynes could directly convert into corresponding poly-substituted allene compounds. In addition, this efficient method enjoys a broad substrate scope and provides a series of 1,5-difunctionalized allenes in a one-pot reaction.

20.
Front Cell Infect Microbiol ; 12: 1030315, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36452303

RESUMEN

Objective: Overactive bladder (OAB) is a disease that seriously affects patients' quality of life and mental health. To address this issue, more and more researchers are examining the relationship between OAB treatment and urinary microecology. In this study, we sought to determine whether differences in treatment efficacy were related to microbiome diversity and composition as well as the abundance of specific genera. Machine learning algorithms were used to construct predictive models for urine microbiota-based treatment of OAB. Methods: Urine samples were obtained from 64 adult female OAB patients for 16S rRNA gene sequencing. Patients' overactive bladder symptom scores (OABSS) were collected before and after mirabegron treatment and patients were divided into effective and ineffective groups. The relationship between the relative abundance of certain genera and OABSS were analyzed. Three machine learning algorithms, including random forest (RF), supporting vector machine (SVM) and eXtreme gradient boosting (XGBoost) were utilized to predict the therapeutic effect of mirabegron based on the relative abundance of certain genera in OAB patients' urine microbiome. Results: The species composition of the two groups differed. For one, the relative abundance of Lactobacillus was significantly higher in the effective group than in the ineffective group. In addition, the relative abundance of Gardnerella and Prevotella in the effective group was significantly lower than in the ineffective group. Alpha-diversity and beta-diversity differed significantly between the two groups. LEfSe analysis revealed that Lactobacillus abundance increased while Prevotella and Gardnerella abundance decreased in the effective group. The Lactobacillus abundance ROC curve had high predictive accuracy. The OABSS after treatment was negatively correlated with the abundance of Lactobacillus, whereas the relationship between OABSS and Prevotella and Gardnerella showed the opposite trend. In addition, RF, SVM and XGBoost models demonstrated high predictive ability to assess the effect of mirabegron in OAB patients in the test cohort. Conclusions: The results of this study indicate that urinary microbiota might influence the efficacy of mirabegron, and that Lactobacillus might be a potential marker for evaluating the therapeutic efficacy of mirabegron in OAB patients.


Asunto(s)
Vejiga Urinaria Hiperactiva , Adulto , Humanos , Femenino , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Lactobacillus , Calidad de Vida , ARN Ribosómico 16S/genética , Gardnerella , Prevotella
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