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A simple and general copper-catalyzed method has been developed for transformations of various functional groups (-I, -N(3), -SO(2)R, -OH, -NH(2), and -NO(2)) on aromatic rings from arylboronic acids in water under air. The protocol uses cheap and readily available inorganic salts (KI, NaN(3), NaSO(2)R, NaOH, NaNO(2)) and aqueous ammonia as the functional-group sources, simple Cu(2)O/NH(3) as the catalyst system, environmentally friendly water as the solvent, and oxygen in air as the oxidant. Importantly, the copper catalyst system in water was recyclable. This study should provide a useful strategy for interconversions of the functional groups on aromatic rings.

Efficient and practical visible-light photoredox borylation of aryl halides and subsequent aerobic oxidative hydroxylation were developed. The protocols use readily available aryl halides and bis(pinacolato)diboron as the starting materials, fac-Ir(ppy) as the photocatalyst, and corresponding arylboronic esters and phenols were obtained in good yields. The methods show some advantages including simple equipment, mild conditions, easy operation, and wide substrate scope. Therefore, they should provide a valuable strategy for chemical transformations.

The formation of aryl C-S bonds is an important chemical transformation because aryl sulfides are valuable building blocks for the synthesis of biologically and pharmaceutically active molecules and organic materials. Aryl sulfides have traditionally been synthesized through the transition-metal-catalyzed cross-coupling of aryl halides with thiols. However, the aryl halides used are usually bromides and iodides; readily available, low-cost aryl chlorides often not reactive enough. Furthermore, the deactivation of transition-metal catalysts by thiols has forced chemists to use high catalyst loadings, specially designed ligands, high temperatures, and/or strong bases, thus leading to high costs and the incompatibility of some functional groups. Herein, we describe a simple and efficient visible-light photoredox arylation of thiols with aryl halides at room temperature. More importantly, various aryl chlorides are also effective arylation reagents under the present conditions.

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Transforming growth factor-b (TGF-b) is involved in actin cytoskeleton reorganization and tumor progression. Fascin1, an actin-binding protein, increases cell invasiveness and motility in various transformed cells. To determine whether fascin1 is an important mediator of the tumor response to TGF-b, we applied the small interfering RNA (siRNA) technique to silence fascin1 in gastric cancer (GC) cells MKN45. Results showed that the effects of TGF-b1 on GC cells invasion and metastasis were mediated by tumor production of fascin1; furthermore, it was found that TGF-b1-induced fascin1 expression was suppressed by the specific inhibitors of JNK and ERK pathways, SP6001125 and PD98059, respectively, but not by transient transfection of Smad2 and Smad4 siRNA. Our data for the first time demonstrated that fascin1 is an important mediator of TGF-b1-induced invasion and metastasis of GC cells, which involves JNK and ERK signaling pathways.

Carboxylica cids and their derivatives are abundant and inexpensive organic and biomass-derived platform molecules,a nd their conversion into high-value products represents an important goal. Recently,v isible-light photoredox decarboxylative couplingr eactions have become an important chemical transformation because of their wide sub-strate scope, mild reaction conditions, high efficiency,a nd practicability.T his review summarizes recenta dvances in visible-light photoredox decarboxylative coupling strategies, which include the formation of CÀCa nd CÀY( Y= heteroatom) bonds.Scheme1.Visible-lightp hotoredox decarboxylative Michael additiono fN-(acyloxy)phthalimides (LED = light-emitting diode).Scheme3.Visible-lightp hotoredox synthesis of unnatural chiral amino acids (CFL = compact fluorescent light).