Nickel-catalysed radical tandem cyclisation/arylation: practical synthesis of 4-benzyl-3,3-difluoro-γ-lactams.

Enabled by nickel catalysis, a practical access to the synthesis of 4-benzyl-3,3-difluoro-γ-lactams has been developed via radical tandem cyclisation/arylation. This method features a nickel catalyst, high reaction efficiency, and good substrate tolerance and scope. This protocol proceeds through an intramolecular radical addition to form a primary alkyl radical followed by intermolecular Suzuki-type coupling.

Chemical strategies for the synthesis of peptide-oligonucleotide conjugates.

The use of synthetic oligonucleotides and their mimics to inhibit gene expression by hybridizing with their target sequences has been hindered by their poor cellular uptake and inability to reach the nucleus. Covalent postsynthesis or solid-phase conjugation of peptides to oligonucleotides offers a possible solution to these problems. As feasible chemistry is a prerequisite for biological studies, development of efficient and reproducible approaches for convenient preparation of peptide-oligonucleotide conjugates has become a subject of considerable importance. The present review gives an account of the main synthetic methods available to prepare covalent conjugation of peptides to oligonucleotides.