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α-Halo- N-tosylhydrazones are explored as reagents for the multiple carbon-carbon bond formations in palladium-catalyzed three-component reactions. A strategy has been designed for this transformation by using a nucleophile to react with the azoalkene intermediate formed in situ from the α-halo- N-tosylhydrazone to generate the diazo intermediate, which is further subjected to palladium-catalyzed C−C bond forming reactions with aryl iodides. [ABSTRACT FROM AUTHOR]

Chronic infection with Schistosoma japonicum is an important cause of hepatic fibrosis (HF). Human 9q33.3 is one of the most important loci for stress-related diseases. We examined the potential associations of 43 single-nucleotide polymorphisms (SNPs) with S. japonicum infection and HF in epidemic region in China. We identified a SNP (rs10118570 GG in mitogen-activated protein kinase associated protein 1, MAPKAP1) contributes to anti-infection (adjusted OR = 0.35) and anti-fibrogenesis (adjusted RR = 0.44) in the discovery study. Replicative and combined studies showed consistent protective quality for this genotype (replicative: adjusted OR = 0.37 for anti-infection, and adjusted RR = 0.40 for anti-fibrogenesis; Combined: adjusted OR = 0.45 for anti-infection, and adjusted RR = 0.42 for anti-fibrogenesis). Univariate and multivariate analysis in the discovery, replicative and combined studies, suggested that durations (years), splenomegaly, serum ALB and rs10118570 were independent predictors influencing the fibrogenesis. The analysis of gene-gene interaction showed rs10118570 functions independently. We conclude that MAPKAP1 may represent a novel anti-infection and anti-fibrogenesis genomic locus in chronic schistosomiasis japonica. And rs10118570 may be a potential biomarker and target for the treatment of this life-threatening ancient disease. [ABSTRACT FROM AUTHOR]

Comprehensive Summary We herein describe a Cp*RhIII‐catalyzed C(sp3)–H mono‐arylation of 8‐methylquinolines with benign arylsilanes. The use of 1‐adamantane carboxylic acid can benefit the efficiency in this transformation, and AgF was both activator and reoxidant. Control experiments indicated inability of C—H cleavage in determining the rate of the reaction. [ABSTRACT FROM AUTHOR]

Background: MicroRNA-584-5p (miR-584-5p) plays an important role in certain types of cancer. However, its precise role in head and neck squamous cell carcinoma (HNSC) remains unknown., Objective: Our aim was to investigate how miR-584-5p influences HNSC., Methods: The Cancer Genome Atlas (TCGA) provided samples for the study. We use statistical methods to evaluate the diagnostic value, the prognostic value, and the correlation with the clinical features of miR-584-5p. We analyze the target genes and the regulatory network of miR- 584-5p. Quantitative reverse transcriptase PCR (qRT-PCR) confirmed the expression of miR- 584-5p in HNSC cell lines., Results: MiR-584-5p expression of miR-584-5p varied significantly among different types of cancer. A notable correlation was observed between elevated miR-584-5p expression and gender (p < 0.001) and histological grade (p < 0.001). Furthermore, high levels of miR-584-5p were found to be associated with a decrease in overall survival (HR: 1.44; 95% CI: 1.10-1.88; p = 0.007), progression-free survival (HR: 1.35; 95% CI: 1.02-1.79; p = 0.035) and disease-specific survival (HR: 1.54; 95% CI: 1.09-2.18; p = 0.016) in the context of HNSC. miR-584-5p demonstrated independent prognostic significance in HNSC and potentially contributes to disease progression through multiple pathways, such as dilated cardiomyopathy and hypertrophic cardiomyopathy. In particular, HNSC cell lines exhibited a substantial upregulation of miR-584-5p compared to normal epithelial cells., Conclusions: It is possible that miR-584-5p could serve as a promising patent for a therapeutic target and prognostic biomarker for people with HNSC., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Herein, rhodium(III)-catalyzed β-C(sp 2 )-H alkenylation and alkylation of enamides are presented using readily accessible allylic alcohols by switching the reaction conditions. This tunable transformation has been applied to a wide range of substrates and typically proceeded with excellent regioselectivity and stereoselectivity as well as with good functional group tolerance. The catalytic system offers an efficient approach for synthesizing various functionalized enamides bearing N -(2 Z ,4 E )-butadiene and ( Z )-β-C(sp 2 )-H alkylated enamides. In addition, mechanistic experiments suggest that Rh(III)-catalyzed C-H activation is not related to the critical step.

We report a chelation-assisted C-H arylation of various indoles with sterically and electronically diverse (hetero)arylsilanes enabled by cost-effective Cp*-free cobalt catalysis. Key to the success of this strategy is the judicious choice of copper(II) fluoride as a bifunctional sliane activator and catalyst reoxidant. This methodology features a broad substrate scope and good functional group compatibility. The synthetic versatility of this protocol has been highlighted by the gram-scale synthesis and late-stage diversification of biologically active molecules.

In this study, we report a pH-/thermo-responsive hydrogel formed by N , N '-dibenzoyl-l-cystine (DBC). It is difficult to dissolve DBC in water even on heating, and it exhibits no gelation ability. Interestingly, DBC is readily soluble in NaOH solution at room temperature and the self-assembled hydrogels are obtained by adjusting the basic DBC aqueous solution with HCl to achieve a given pH value (<3.5). When NaOH is added to the hydrogel (pH > 9.4), it becomes a sol again. This small-molecule hydrogel is characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, rheological measurement and differential scanning calorimetry. The results indicate that the DBC hydrogel exhibits excellent mechanical properties, thermo-reversibility, and pH-responsive properties. Fortunately, the single crystal of DBC is obtained by volatilizing its acid aqueous solution. It crystallizes in the monoclinic space group P 2 1 ( Z = 2) with lattice parameters a = 10.8180 (11) Å, b = 9.0405 (9) Å, c = 10.9871 (11) Å and β = 90.798 (3)°. By comparing the X-ray diffraction result of the DBC single crystal with that of its xerogel, the self-assembled structure of DBC in hydrogel has been ascertained. The gelators are self-assembled via strong intermolecular hydrogen bonds linking neighboring amide and carboxyl groups, π-π stacking interactions for aromatic rings, and hydrogen bonds between water molecules. In addition, the release behavior of salicylic acid (SA) molecules from the DBC gel is also investigated taking into account the DBC concentration, phosphate buffer solution (PBS) pH and SA concentration. When the concentrations of DBC and SA are 3.0 g L -1 and 200 mg L -1 , respectively, the release ratio in PBS (pH = 4.0) reaches 58.02%. The diffusion-controlled mechanism is in accordance with Fickian diffusion control within the given time range., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

A straightforward N-trifluoroethylation of anilines has been developed based on silver-catalyzed N-H insertions with 2,2,2-trifluorodiazoethane (CF3CHN2). Mechanistically, the reaction is proposed to involve migratory insertion of a silver carbene as the key step. In contrast, when amides are employed as the substrates under similar reaction conditions, O-trifluoroethylation occurs to afford trifluoroethyl imidates., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose: Observational studies have recently focused on the association between heme oxygenase-1 (HMOX1) gene promoter polymorphisms and cancer risk. However, conflicting results have been obtained. To derive a precise estimate of the association, a systematic review and meta-analysis were conducted., Methods: This study followed the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. PubMed, Medline, Embase and Web of Knowledge were systematically searched for relevant studies. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for the allelic and genotypic comparisons according to the homozygous, heterozygous, dominant, and recessive genetic models. Between-study heterogeneity was quantified through I2 statistics, and publication bias was appraised by using funnel plots. Sensitivity analyses were conducted to evaluate the robustness of the meta-analysis findings., Results: Meta-analysis of 9 studies involving 2491 cases and 3380 controls did not reveal any significant association of the HMOX-1 (GT)n and 413A>T polymorphisms with cancer risk. Stratified analysis by ethnicity showed a statistically significant association between (GT)n repeat length variant and susceptibility to cancer for the heterozygous genetic model among Asian populations (OR=1.42, 95% CI: 1.04-1.95, Pheterogeneity=0.218), which is a robust finding according to sensitivity analysis. Funnel plot inspection did not reveal any publication bias., Conclusion: In conclusion, this study comprehensively examined the available literature on the association of HMOX-1 (GT)n and 413A>T polymorphisms with cancer risk. Meta-analysis results suggest (GT)n repeat length polymorphism as a potential susceptibility variant for cancer in Asians. Additional large-scale and well-designed studies are needed to confirm these results.