A highly efficient and facile cobalt-catalyzed C-H activation and peroxidation of 2-oxindoles was reported, which provides a new pathway for the synthesis of biologically active 3-peroxy-2-oxindoles from readily available starting materials in excellent chemical yields. The resulting products could be further transformed into various substituted 3-peroxyoxindoles in good to excellent yields. The developed method has been successfully applied to the synthesis of the natural product (±)-N-[2-(3-hydroxy-2-oxo-2,3-dihydro-1H-indol-3-yl)ethyl]acetamide.

Labelling and detecting 5‐formylpyrimidine is essential to understand its biological function. Herein, we describe a visible‐light triggered and catalyst‐free reaction in which 5‐formylcytidine RNA can be selectively labelled with 2‐thioaniline under the irradiation of a commercial blue LED light to generate fluorogenic 5‐(benzothiazol‐2‐yl) cytidine.magnified image

A new approach for the oxidation of 5‐methyl cytidine modification in nucleic acids to 5‐formyl cytidine is reported. This method displays excellent chemo‐/bio‐ selectivity, from which the methyl group in cytidine nucleosides could be selectively oxidized to biologically important formyl functionality without interfering with other cellular biomolecules.magnified image