Bromide is best : The first [2]rotaxane incorporating the triazolium anion‐binding motif is prepared using bromide anion templation. Preliminary anion‐binding investigations reveal that the rotaxane exhibits the rare selectivity preference for bromide over chloride ions.
From sugar to cycloadduct : The effect of the trans‐acetonide blocking group and the stereochemistry of the substituents on the regio‐ and stereoselectivity in the intramolecular nitrone–alkene cycloaddition (INAC) reaction of hept‐6‐enoses (see scheme) is reported and studied by using theoretical analysis.
One's enough : The direct observation of a DNA‐polymerase‐based “sequencing engine” using single‐molecule detection recently allowed single‐molecule sequencing by synthesis in real time. Nucleotides with a fluorescent marker at the 5′‐phosphate unit and zero‐mode waveguides are crucial components of this approach, which at last promises low‐cost genome‐scale sequencing.
Another way to dienes : The ruthenium‐catalyzed 6‐endo‐cycloisomerization of 1,5‐enynes gives the corresponding 1,3‐cyclohexadienes in high to excellent yields. This novel synthetic and catalytic method constitutes another way to selectively prepare 1,3‐cyclohexadienes, this cyclic diene skeleton being a core subunit in many natural products and a useful building block for a variety of organic transformations.
Rings around a ring : The synthesis, characterization, material properties and biological studies of novel hexakis porphyrinato cyclotriphosphazene systems (see scheme) and their metal derivatives are described.
Light on target : Silica‐coated upconverting nanophosphor (UCNP) nanocomposites have been synthesized with organic dye (fluorescein isothiocyanate, FITC) incorporated in the silica shell. The nanocomposites are well dispersed and have good photostability and biocompatibility. These nanocomposites readily conjugated with folic acid for targeted multimodal bioimaging (see schematic representation).
Enzyme in action : The accumulated single‐molecule image (see picture) of phospholipase A2 (PLA2) 15–21 min after its injection on a lipid membrane shows transient interactions of PLA2 (blue) with the membrane surface and stable binding to the boundaries of membrane structure defects. The adsorbed PLA2 molecules move with a speed below the experimental resolution of 40 nm min?1.
Ignoring the STOP sign : A pyrrolysine analogue bearing a terminal alkyne was site‐specifically incorporated into recombinant calmodulin (CaM) through a UAG codon. The resulting protein was labeled with an azide‐containing dye using a copper(I)‐catalyzed click reaction. Subsequent application of an orthogonal cysteine tagging method yielded a CaM labeled with two distinct fluorophores that enabled its study by FRET spectroscopy.
Lithium makes the difference : A simple strategy for the synthesis of lithium‐doped porous metal–organic frameworks (MOFs) is developed (see structure; C black, O red, AlO6 blue octahedra), thus paving the way for the facile preparation of lithium‐doped MOFs. Moreover, the significant increase in hydrogen adsorption predicted by theoretical calculations is observed.
Sheet‐like mimic enzyme : A novel nanostructure (see figure) of sheet‐like FeS with peroxidase‐like activity was synthesized as a mimic enzyme for the development of amperometric transducers and biocatalysts.
