Rearrangement Reaction Based on the Structure of N-Fluoro- N-alkyl Benzenesulfonamide.

A novel rearrangement reaction based on the structure of N-fluoro- N-alkyl benzenesulfonamide was developed. The reaction proceeded readily at 50 °C in formic acid and generated a variety of benzenesulfonamides and aldehydes or ketones simultaneously. The reaction mechanism is believed to be a concerted mechanism that consist of 1,2-aryl migration with the departure of fluorine anion via an SN2 mechanism. This rearrangement reaction features an interesting reaction mechanism, mild reaction conditions, simple operations, and a broad substrate scope.

The prognostic value of HOTAIR for predicting long-term prognosis of patients with gastrointestinal cancers.

BACKGROUND: Increased expression of HOX transcription antisense RNA (HOTAIR) has been reported to be associated with unfavorable prognosis in cancer patients. Several studies have evaluated the significance of HOTAIR in the development and progression of gastrointestinal cancers (GICs). METHODS: Systematic literature retrieval was performed by searching keywords in several electronic databases, including PubMed, Embase, Web of Science, CNKI, Springer, Google Scholar, and GEO. Relevant articles on association between HOTAIR expression levels and prognosis in patients with GIC were collected and screened with eligible criteria. The RevMan 5.2 software and Stata SE12.0 software was applied. RESULTS: A total of 1297 patients from 15 eligible articles were included in this meta-analysis. The results revealed that increased expression of HOTAIR was significantly associated with shorter overall survival (OS) in GIC patients [hazard ratio (HR) = 1.93, 95% CI: 1.64-2.26], as well as poorer disease-free survival (DFS) (HR = 2.79; 95% CI: 1.38-5.63). Additionally, the pooled odds ratio (OR) indicated that increased HOTAIR was associated with clinicopathological parameters, including lymph node metastasis (OR = 2.48, 95% CI: 1.71-3.61), distant metastasis (OR = 4.34, 95% CI: 2.12-8.91), poor tumor differentiation (OR = 2.90, 95% CI: 1.45-5.80), lymphovascular invasion (OR = 2.86, 95% CI: 1.83-4.46), high depth of tumor invasion (OR = 2.07, 95% CI: 1.36-3.16), and poor clinical stage (OR = 2.72, 95% CI: 1.70-4.35). In survival analysis through the Kaplan-Meier plotter database, enhanced level of HOTAIR was associated with better OS and DFS in gastric cancer patients. CONCLUSIONS: High expression level of HOTAIR was related to poor clinical outcome of GIC patients. The HOTAIR could be applied as potential biomarker for assessing the prognosis. Further well-designed studies should be performed to verify the clinical applications of HOTAIR in GIC.

microRNA-21 promotes osteogenic differentiation of mesenchymal stem cells by the PI3K/ß-catenin pathway.

Osteogenesis of mesenchymal stem cells (MSCs) is essential for bone repair. Recently, microRNAs have been proven to play an important role in the regulation of MSC differentiation, including osteogenesis. Here, the function of microRNA-21 (miR-21) in the osteogenic differentiation of human umbilical cord mesenchymal stem cells (hUMSCs) was investigated. Briefly, the miR-21 mimics (m-miR-21) and the antisense miR-21 (as-miR-21) were transfected to hUMSCs, and the capacity of miR-21 for the osteogenic differentiation of hUMSCs was evaluated by the expression of osteogenic markers encoding alkaline phosphatase (ALP), runt-related gene-2 (RUNX-2) and osteocalcin (OCN), as well as by Alizarin red S staining. The results indicated that the overexpression of miR-21 elevated the expression level of the osteogenesis-related genes of hUMSCs. During this process, the PI3K-AKT signaling pathway activity had an increasing tendency responding to miR-21 up-regulation. This enhancement promoted the phosphorylation of GSK-3ß, leading to the stabilization and high concentration accumulation of ß-catenin in cytoplasm to activate the transcription of RUNX-2, and finally increased the osteogenesis of hUMSCs. This work demonstrated that miR-21 and its target PI3K-AKT-GSK3ß pathway played an important role in the osteogenic differentiation of hUMSCs by stabilizing ß-catenin.

Monocarboxylation and intramolecular coupling of butenylated arenes via palladium-catalyzed C-H activation process.

A novel and practical reaction for the direct intramolecular oxidative coupling of butenylated arenes is reported. With the catalysis of Pd(OAc)2, reactions of various butenylated arenes and carboxylic acids with Selectfluor reagent in CH3CN solution afforded the corresponding monocarboxylation/cyclization products in good yields under mild conditions. This research demonstrated an economic method with the synthesis of 2-tetralyl carboxylic esters, a valuable class of bioactive compounds.

One-pot synthesis of functionalized 2,5-dihydrofurans via an amine-promoted Petasis borono-Mannich reaction.

A series of functionalized 2,5-dihydrofurans were efficiently synthesized via an amine-promoted Petasis borono-Mannich reaction of 4-substituted 1,2-oxaborol-2(5H)-ols with salicylaldehydes in high yields. The process, which combines a boronic acid-based Mannich reaction and a highly efficient intramolecular SN2 cyclization, provides a one-step and efficient route toward 2,5-dihydrofurans from simple and stable starting materials.