Interplay between electronic effects imparted by phosphinothiol substituents and steric effects imposed by amino-acid reactants affects the rate of the traceless Staudinger ligation of peptides in a predictable manner.

Click chemistry is a powerful chemical reaction with excellent bioorthogonality features: biocompatible, rapid and highly specific in biological environments. For glycobiology, bioorthogonal click chemistry has created a new method for glycan non-invasive imaging in living systems, selective metabolic engineering, and offered an elite chemical handle for biological manipulation and glycomics st...

Eighteen Palaearctic taxa of the Mniotype adusta species-group are reviewed. One new species (M. kobyakovi Volynkin, Matov & Behounek, sp. n.) and six new subspecies (M. lama kortka Volynkin, Matov & Behounek, ssp. n., M. lama etugen Volynkin, Matov & Behounek, ssp. n., M. lama ayubaevorum Volynkin, Matov & Behounek, ssp. n., M. adusta poltavskyi Volynkin, Matov & Behounek, ssp. n., M. adjuncta...

Department of Physics, University of California at Berkeley, Berkeley, California 94720, United States Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States. CIC nanoGUNE, Donostia San Sebastián 20018, Spain Ikerbasque, Basque Foundation for Science, Bilbao 48011, Spain Departamento de Física Teórica de la Materia Condensada...

The covalent attachment of polyethylene glycol (PEG) to therapeutic proteins can improve their physicochemical properties. In this work we utilized the non-natural amino acid p-azidophenylalanine (pAzF) in combination with the chemoselective Staudinger-phosphite reaction to install branched PEG chains to recombinant unglycosylated erythropoietin (EPO) at each single naturally occurring glycosyl...

Using small molecules to control the function of proteins in live cells with complete specificity is highly desirable, but challenging. Here we report a small-molecule switch that can be used to control protein activity. The approach uses a phosphine-mediated Staudinger reduction to activate protein function. Genetic encoding of an ortho-azidobenzyloxycarbonyl amino acid using a pyrrolysyl tran...

The Palaearctic Hylaea fasciaria (Linnaeus, 1758) species group is revised (Lepidoptera: Geometridae, Ennominae). Four taxa are considered valid at species level: H. fasciaria (Linnaeus, 1758), H. pinicolaria (Bellier, 1861), H. compararia (Staudinger, 1894) and one new species, H. mediterranea, from Italy: Sicily, Calabria and Molise. The following taxonomic changes are proposed: Ellopia cedri...

The stereoselectivity of the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents was investigated experimentally by determination of the product stereochemistry and theoretically via DFT calculations. The results indicate that imines preferentially attack the less sterically hindered exo-side of the ketenes to generate zwitterionic intermediates. Subsequen...