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The air mediated radical alkylation of cyclic aldimines via autoxidation of alkylboronic acids has been realized under mild reaction conditions. By simply heating cyclic aldimines with alkylboronic acid using air as sole oxidant, this protocol provides a catalyst‐free access to a variety of alkylated cyclic aldimines with 21–91% yields. Preliminary mechanistic studies suggest that a radical pathway might be involved in the reaction. [ABSTRACT FROM AUTHOR]

An efficient and versatile copper- or iron-catalyzed direct β-C(sp2)–H methylation of enamides by using dicumyl peroxide (DCP) as the methylating reagent has been developed. This methodology provides convenient access to a wide range of β-C(sp2)-methylated enamides with exclusive E-selective control in moderate to good yields. Mechanistic studies reveal that a methyl radical was involved in this transformation. Notably, this method features cheap copper or iron salts as the catalyst, a simple procedure, commercially available methylation reagents, a broad substrate scope, and excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

Established herein is a Rh(III)-catalyzed direct ortho-C–H diarylation of arylsulfoximine derivatives with diverse arylsilanes. The protocol demonstrates a wide scope of substrates, good functional group tolerance and the adoption of environmentally friendly arylsilanes, allowing the synthesis of potentially valuable tricyclic arylsulfoximine derivatives. [ABSTRACT FROM AUTHOR]

Herein, we disclosed an electrochemically induced method for the regio‐ and stereoselective (E)‐β‐C(sp2)−H trifluoromethylation of enamides by employing readily available and inexpensive Langlois' reagent (CF3SO2Na). Preliminary mechanistic studies indicate the involvement of free radicals in the process. The exogenous oxidant‐free reaction proceeds in an undivided electrochemical cell under mild conditions and allows for the accomplishment of the trifluoromethylation products with exclusive E‐selective control. The methodology is featured by catalyst‐free, simple setup, and broad substrate scopes of enamides with good functional group tolerance. Using ArSO2Na as the coupling partner, the corresponding (E)‐β‐C(sp2)−H arylsulfonylated enamides products are obtained under standard reaction conditions. [ABSTRACT FROM AUTHOR]

Herein, we report a Mn(OAc)2‐promoted formal dehydrative dehydroaromatizing [4+2] cycloaddition of enamides with maleimides for the construction of pyridine rings to access the diverse synthetically valuable pyrrolo[3,4‐c]‐pyridine derivatives. This protocol allows two C−C bond formation for the assembly of pyridine derivatives from enamides synthesizable in two steps and inexpensive maleimides, which exhibits broad substrate scope and good functional group compatibility. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient copper‐catalyzed aerobic Chan‐Lam type N‐arylation of various indoles and anilines with structurally diverse aryltrialkoxysilanes under mild conditions. This silicon‐based protocol enables the efficient C−N cross‐coupling of indoles and anilines with user‐friendly organosilicon reagents by employing inexpensive and nontoxic Cu(OAc)2, which is efficient and practical without the addition of other ligands, bases, and metal oxidants. This transformation is compatible with a wide range of substrates, and typically proceeds with high efficiency as well as with good functional group compatibility. A plausible mechanism involving the formation of Cu(III) species in the reaction was tentatively proposed. [ABSTRACT FROM AUTHOR]

Aberrant lipid metabolism has recently been recognized as a new hallmark of malignancy, but the characteristics of fatty acid metabolism in breast cancer stem cells (BCSC) and potential interventions targeting this pathway remain to be addressed. Here, by using the in vitro BCSC models, mammosphere‐derived MCF‐7 cells and HMLE‐Twist‐ER cells, we found that the cells with stem cell‐like properties exhibited a very distinct profile of fatty acid metabolism compared with that of their parental cancer cells, characterized by increased lipogenesis, especially the activity of stearoyl‐CoA desaturase 1 (SCD1) responsible for the production of monounsaturated fatty acids, and augmented synthesis and utilization of the omega‐6 arachidonic acid (AA). Suppression of SCD1 activity by either enzyme inhibitors or small interfering RNA (siRNA) knockdown strikingly limited self‐renewal and growth of the BCSC, suggesting a key role for SCD1 in BCSC proliferation. Furthermore, elevated levels of SCD1 and other lipogenic enzymes were observed in human breast cancer tissues relative to the noncancer tissues from the same patients and correlated with the pathological grades. Interestingly, treatment of BCSC with omega‐3 fatty acids, eicosapentaenoic acid and docosahexaenoic acid, effectively downregulated the expression of the lipogenic enzymes and markedly suppressed BCSC self‐renewal and growth. Dietary supplementation of nude mice bearing BCSC‐derived tumors with omega‐3 fatty acids also significantly reduced their tumor load. These findings have demonstrated that increased lipogenesis is critical for self‐renewal and growth of BCSC, and that omega‐3 fatty acids are effective in targeting this pathway to exert their anticancer effect. [ABSTRACT FROM AUTHOR]

Herein we report a facile method for the synthesis of arylphosphonates via copper‐mediated the cross‐coupling reaction in the presence of 1, 10‐Phenanthroline and Ag2O. This method features a broad scope with respect to both the arylsilanes and H‐phosphonate diesters. Mechanistically, the reaction is proposed to involve oxidation by phosphinyl radical and reductive elimination process as the two key steps. With the optimized conditions established, various arylphosphonates were obtained up to 74% yield. This protocol is the first example of copper mediated the Ar−P bond formation of various arylsilanes with H‐phosphonates, and this novel methodology expands the applications of low cost and toxicity copper reagent in Ar−P bond construction. [ABSTRACT FROM AUTHOR]

The genome-wide association study (GWAS) is an effective method to detect single-nucleotide polymorphisms (SNPs) of multiple individual genes based on linkage disequilibrium (LD). GWAS examines genotypes and distinguishing gene characteristics that are exhibited in diseases. In the past few decades, more and more literature has reported the results of applying GWAS to study tumors. Although many pleiotropic loci associated with complex phenotypes have been identified by GWAS, the biological functions of many genetic variation loci remain unclear, and the genetic mechanisms of most complex phenotypes cannot be systematically explained. In this article, we will review the new findings of several tumor types, and categorize the new sites and mechanisms that have recently been discovered. We linked the mechanisms of action of various tumors and searched for links to related gene expression pathways. We found that susceptible sites can be divided into hub genes and peripheral genes; the two interact to link gene expression in a variety of diseases. [ABSTRACT FROM AUTHOR]

The patients with high microsatellite instability (MSI-H)/mismatch repair deficient (dMMR) tumors recently have been reported that can benefit from immunotherapy, and MSI can be used as a genetic instability of a tumor detection index. However, many studies have shown that there are many heterogeneous phenomena in patients with MSI tumors in terms of immunotherapy, prognosis and chemotherapy sensitivity. Here we mainly review the research results of MSI detection methods, the mechanisms of MSI occurrence and its relationship with related tumors, aiming to make a brief analysis of the current research status of MSI and provide comparable reference and guidance value for further research in this field. [ABSTRACT FROM AUTHOR]

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]

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. [ABSTRACT FROM AUTHOR]

A novel and efficient methodology that allows for the construction of Ar–P bonds via the Pd-catalyzed oxidative cross-coupling reaction of various arylsilanes with H-phosphonates leading to valuable arylphosphonates has been developed. [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]

Background: Epidemiological studies have evaluated the association between 3801T>C polymorphism of CYP1A1 gene and the risk for idiopathic male infertility, but the results are inconclusive. We aimed to derive a more precise estimation of the relationship by conducting a meta-analysis of case-control studies. Methods: This study conformed to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase and CNKI databases were searched through November 2013 to identify relevant studies. Pooled odds ratios with 95% confidence intervals were used to assess the strength of the association between CYP1A1 3801T>C polymorphism and idiopathic male infertility risk. Q-test was performed to evaluate between-study heterogeneity and publication bias was appraised using funnel plots. Sensitivity analyses were conducted to evaluate the robustness of meta-analysis findings. Results: Six studies involving 1,060 cases and 1,225 controls were included in this meta-analysis. Overall, significant associations between 3801T>C polymorphism and idiopathic male infertility risk were observed in allelic comparison (OR = 1.36, 95% CI: 1.01–1.83), homozygous model (OR = 2.18, 95% CI: 1.15–4.12), and recessive model (OR = 1.86, 95% CI: 1.09–3.20), with robust findings according to sensitivity analyses. However, subgroup analyses did not further identify the susceptibility to idiopathic male infertility in all comparisons. Funnel plot inspections did not reveal evidence of publication bias. Conclusions: The current meta-analysis provides evidence of a significant association between CYP1A1 3801T>C polymorphism and idiopathic male infertility risk. Considering the limitation inherited from the eligible studies, further confirmation in large-scale and well-designed studies is needed. [ABSTRACT FROM AUTHOR]

Background: Overexpression of phosphatase of regenerating liver 3 (PRL-3) has been implicated in gastric cancer (GC) metastasis. Epidemiological studies have evaluated the relationship between PRL-3 expression and prognosis in GC. However, results still remains controversial. In this study, a meta-analysis was performed to evaluate the association of PRL-3 expression with overall survival (OS) and clinicopathological characteristics. Methods: Literature databases were searched to identify eligible studies dated until April 2013. Summary hazard ratios (HRs) or odds ratios (ORs) with 95% confidence interval (95% CI) were calculated to estimate the association. Results: A total of 1380 GC patients from six studies were included in the meta-analysis. Overall, the combined HR estimate for OS in a random-effect model was 1.89 (95% CI = 1.38–2.60; P<0.001). Results showed that PRL-3 overexpression was significantly associated with OS, indicating that it may be a biomarker for poor prognosis of GC. Both subgroup and sensitivity analyses further identified the prognostic role of PRL-3 expression in GC patients. Moreover, PRL-3 overexpression was significantly associated with tumor stage (OR = 2.25; 95% CI = 1.63–3.12; P<0.001), depth of invasion (OR = 2.03; 95% CI = 1.38–2.98; P<0.001), vascular invasion (OR = 2.52; 95% CI = 1.79–3.56; P<0.001), lymphatic invasion (OR = 3.74; 95% CI = 2.49–5.63; P<0.001), and lymph node metastasis (OR = 4.56; 95% CI = 2.37–8.76; P<0.001). However, when age, sex, tumor size, and tumor differentiation were considered, no obvious association was observed. Conclusions: This meta-analysis reveals significant association of PRL-3 overexpression with OS and some clinicopathological features in GC. PRL-3 may be a predicative factor of poor prognosis and aggressive tumor behavior in GC patients. [ABSTRACT FROM AUTHOR]

α-Halo-N-tosylhydrazones are employed as reagents for the formation of multiple carbon–carbon bonds in the three-component reactions. In this transformation, a strategy has been designed to generate the diazo intermediate by using a nucleophile to react with the azoalkene intermediate generated in situ from the α-halo-N-tosylhydrazone. The diazo intermediate thus generated further undergoes transition-metal-free C–C bond forming reaction with arylboronic acids. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed cross-coupling reaction of electron-deficient aryl fluorides with aryl N-tosylhydrazones has been reported. Mechanistically, this approach involves C–F bond activation and migratory insertion of palladium carbene as the two key steps. [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]

A wide range of substrates is applied under mild reaction conditions. [ABSTRACT FROM AUTHOR]

For the N-trifluoroethylation of anilines, a formal N-H insertion reaction is suggested involving a Ag(I)/carbene formation and subsequent amine ligand migratory insertion. [ABSTRACT FROM AUTHOR]

An abstract of the article "Palladium-catalyzed cross-coupling of aryl fluorides with N-tosylhydrazones via C-F bond activation," by H. Lou and colleagues is presented.