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The smallest catalyst : A new strategy to control chemical synthesis by exposure to low‐energy electrons relies on the electrostatic attraction caused by the soft ionization of one of the reaction partners. This approach was used to induce a reaction between C2H4 and NH3 yielding aminoethane. The reaction resembles a hydroamination except that the electron beam replaces the catalyst used in the organic synthesis.

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Easy and direct : Regioselective Mizoroki–Heck‐coupling reactions using heteroaromatic tosylates as electrophiles were achieved, thus providing direct and easy access to highly functionalized α‐heteroarylvinyl amides and ethers.

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Exciton migration! Spectroscopic analyses and extensive molecular dynamics studies revealed a well‐defined 41 helix in which the perylene molecules (see figure) form four “helter‐skelter‐like” overlapping pathways along which excitons and electrons can rapidly migrate.

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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.

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An N for Ir : The synthesis and X‐ray crystal structure of a late‐transition‐metal complex with a terminal nitrido ligand and its hydrogenation to the related amido complex are reported (see scheme).

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Eradicating hedgehogs : The title molecule has been previously identified as a potent inhibitor of the Hedgehog signaling pathway, which gives embryonic cells information needed to develop properly. This molecule is shown to modulate Hedgehog target gene expression by depolymerizing microtubules, thus revealing dual roles of the cytoskeleton in pathway regulation (see figure).

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Let's stick together : The gelation ability of a dendritic gelator has been enhanced by its complexation with a polyelectrolyte (see figure). This concept provides a route to construct novel functional or ordered materials by complexation of other low‐molecular‐mass functional species with polyelectrolytes.

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The right path : The mechanism of organocatalyzed Michael addition between propanal and methyl vinyl ketone is investigated using the density functional and ab intio methods. The kinetic preference for the formation of key intermediates is established in an effort to identify the competing pathways associated with the reaction. The effect of co‐catalyst/protic solvent on the energetics of the reaction is also studied

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Form and function : The natural product myxopyronin A provides the key to understanding the inhibition of bacterial RNA polymerase and should spark new ideas for the design of new antibiotics against tuberculosis and other infectious diseases.

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Kept in the dark : The non‐photocatalytic generation of free radicals from fine and ultrafine TiO2 particles has been studied by means of a spin‐trapping/ESR spectroscopy technique (see figure). The amount and kind of free radicals generated depends on the crystalline structure, but not on the particle dimensions.

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The shortest He–He distance! r(He–He)=1.265 Å. The electronic interaction between confined pairs of He atoms in the C20H20 dodecahedrane cage is analyzed (see figure). A key observation about bonding that emerges uniquely from endohedral complexes is that a short internuclear separation does not necessarily imply the existence of a chemical bond.

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Life RAFT : A bulky methacrylate monomer, triphenylmethyl methacrylate (TrMA), was polymerized with reversible addition–fragmentation chain transfer (RAFT) agents. Stereogradient polymers in which the isospecificity increased spontaneously as the monomer concentration decreased were formed by a polymerization–depolymerization equilibrium that can convert a less stable growing polymer terminal into a more stable form (see picture).

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Enriched cleavage : An efficient chemoselective cysteine modification of unprotected peptides and proteins has been developed by using electron‐deficient alkynes in aqueous media. Interestingly, terminal alkynone‐modified peptides could be converted back into the unmodified peptides by cleavage by adding thiols under mild conditions (see scheme).

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