Volume 3 Issue 12, December 2011

Michelle Francl wonders how much time chemists should spend learning history.

The scope of dynamic combinatorial chemistry is somewhat limited by the small number of predictably reversible reactions. Now, secondary alcohols are shown to quickly and reversibly react with iminium ions to form hemiaminal ethers, opening up opportunites for their use in the construction of complex — and functional — dynamic architectures.

Thermodynamic measurements show that the most stable structural form of a number of proteins under cellular conditions is fibrillar, implying that their functional states may only be metastable.

Cross-coupling between a racemic secondary alkyl halide and an alkyl borane to produce an enantioenriched alkyl–alkyl product is one of the final substrate combinations to succumb to the synthetically powerful Suzuki–Miyaura methodology.

Mutating RNA one nucleotide at a time and measuring the impact of this on its chemical reactivity provides a strategy for determining its three-dimensional structure, and from there, hopefully, its function.

Autonomous propulsion of microparticles using catalytic olefin polymerization, and directional rotation of a molecule on a metal surface using electrons from the tip of a scanning tunnelling microscope.

Contemporary macromolecular chemistry and physics offer interesting options for making, characterizing and manipulating single polymer chains. Although it is not yet possible to emulate the structural control and functional ability of biopolymers, recent advances have opened up interesting avenues for applications of these synthetic systems in microelectronics, photovoltaics, catalysis and biotechnology.

Cell-laden synthetic hydrogels — formed via a copper-free click reaction between a poly(ethylene glycol) tetra-cyclooctyne and a peptide-diazide — provide a platform to investigate the cells' response to various stimuli during growth. The hydrogel's biochemical aspects are readily controlled by a thiol-ene photocoupling reaction initiated with visible light, whereas the biomechanical properties of the network are altered via a UV-mediated photodegradation.

‘Roaming’ is a recently discovered reaction dynamics phenomenon in which a molecule undergoes frustrated dissociation to radicals, followed by an intramolecular abstraction reaction. An imaging study, with associated high-level ab initio calculations, has now shown that ‘roaming-mediated isomerization’ plays a key role in the photodissociation of nitrobenzene.

The polyprenylated polycyclic acylphloroglucines (PPAPs) are a family of natural products in which a common core is decorated with four different substituents. Here, a synthetic strategy is presented that separates the core building steps from the core decorating steps, offering a general solution to the synthesis of these natural products that will allow investigation of their biological activities.

The reversible covalent binding of mono-alcohols with high affinity is challenging because of their poor nucleophilicity. A multi-component assembly has now been used to achieve reversible binding of secondary alcohols through iminium activation and product stabilization. Moreover, such assemblies can be used to determine alcohol chirality and enantiomeric excess.

One-dimensional wires with metal–metal bonding have been studied for more than a century, but control over structure and properties has remained challenging. Here, palladium–palladium bonding is used to make one-dimensional wires with lengths of up to 750 nm in solution, whose molecular structures can be rationally modified.

Non-coding RNAs are ubiquitous biomolecules with intricate three-dimensional folds that are difficult to characterize. This Article presents an information-rich strategy for inferring RNA structure by combining nucleotide-by-nucleotide mutagenesis with single-nucleotide-resolution chemical mapping.

Intracellular biothiols can degrade nanoparticle monolayers, compromising the function of these potentially promising tools. Here, we describe a label-free method for quantifying the intracellular stability of quantum dot monolayers, using laser desorption/ionization mass spectrometry coupled with inductively coupled plasma mass spectrometry.

The natural product fumagillol has been exploited as a stereochemically rich scaffold for the synthesis of a structurally unique, chemically diverse library with chemotypes distinctly different from the parent structure. Thus, fumagillol has been remodelled into a diverse array of isoindoles, isoquinolines, furans, mopholinones and benzoxazepines.

Sodium, ubiquitous on Earth in living organisms, oceans and minerals — all the way to table salt — may seem like one of the more ordinary elements. Margit S. Müller highlights why we, like the fairytale king, should not take it for granted.