ABSTRACT
Transition-metal-catalyzed directed C-H functionalization with various carbene precursors has been widely employed for constructing a wide range of complex and diverse active molecules through metal carbene migratory insertion processes. Among various carbene precursors, iodonium ylides serve as a novel and emerging carbene precursor with features including easy accessibility, thermal stability and high activity, which have attracted great attention from organic chemists and have achieved tremendous success in organic transformation. In this review, recent progress on the application of iodonium ylides with multifunctional coupling characteristics in C-H bond activation reactions is summarized, and the potential of iodonium ylides is discussed.
ABSTRACT
An efficient 2,2,6,6-tetramethylpiperidinooxy (TEMPO)-mediated hydroxyfluoroalkylation of arylamines with polyfluorinated alcohols via a radical-triggered C(sp2)-H/C(sp3)-H dehydrogenative cross-coupling process was developed. This transformation features simple operation, high atom economy, broad substrate compatibility, and excellent regioselectivity, leading to a series of hydroxyfluoroalkylated arylamine derivatives. Importantly, these synthetic products were further used to evaluate the antitumor activity in cancer cell lines by Cell Counting Kit-8 assay and the outcomes indicated that some compounds show a potent antiproliferative effect.
ABSTRACT
A novel and efficient Rh(III)-catalyzed direct C-H bond tandem annulation of N-nitrosoanilines with 1,3-dicarbonyl compounds through two C-H bond cleavage was developed. This protocol provides a rapid access to a series of valuable tetrahydrocarbazol-4-ones with the feature of readily available starting materials, broad functional group tolerance, and in situ generation of carbene precursors. Importantly, some reaction products exhibited promising antiproliferative activity in cancer cell lines.
ABSTRACT
The aim of the present study was to evaluate the effects of programmed cell death 4 (PDCD4) on cell proliferation and apoptosis, and to elucidate the potential role of the Jun N-terminal kinase (JNK)/c-Jun pathway in human bladder cancer (BCa) cells. Mixed BCa cells were transfected with plasmids containing PDCD4 (PDCD4-pcDNA3). The sensitivity to cisplatin was analyzed using cell viability, invasion/migration, apoptosis, flow cytometry, wound healing and Transwell assays at different transfection times. Furthermore, epithelial-to-mesenchymal transition (EMT) markers were detected by immunofluorescence staining, and the protein expression of c-Jun, and phosphorylated Jun N-terminal kinase (p-JNK) and c-Jun (p-c-Jun, Ser-73) were also tested using western blotting. It was observed that BCa cell proliferation and invasion and tumor growth were significantly inhibited, whereas apoptosis was enhanced in PDCD4-transfected cells treated with cisplatin compared with controls. Moreover, the western blotting and immunofluorescence results demonstrated that PDCD4 upregulated the expression of epithelial cell markers, but downregulated the expression of mesenchymal cell markers. Furthermore, overexpression of PDCD4 reduced the protein levels of p-JNK and p-c-Jun. Taken together, the findings of the present study indicate that PDCD4 enhances the sensitivity of BCa cells to cisplatin, partially via regulation of the JNK/c-Jun pathway, and reverses EMT. In conclusion, the results of the present study suggested that PDCD4, a nuclear/cytoplasmic shuttling protein with multiple functions, plays an important role in the development and progression of human BCa.