Volume 7 Issue 1, January 2015

Michelle Francl wonders what makes benzene resonate with chemists.

A combined experimental and theoretical study of the biosynthesis of a family of antibacterial natural products has uncovered some of the finer details of unusual stereoselectivity observed in a peptide cyclization.

The photoinduced production of hydrogen from HCl is an attractive alternative to water splitting. Insights into this challenging reaction have now been gained using photocrystallography, which provides a snapshot of the structural changes occurring during the elimination of chlorine from a dinuclear rhodium catalyst.

Short peptides are among the most intriguing building blocks in nanotechnology, but it would be very challenging to experimentally study the properties of large numbers of different sequences. Now, a computational analysis of all 8,000 possible tripeptides has been used to identify those with interesting self-assembly behaviour.

Creating chemical systems that can model living systems is far from easy. However, the evolution of oil droplets in water through the application of artificial selective pressure to produce droplets with dramatically different — yet specific — behaviours, is an encouraging step in this direction.

DNA self-assembly has previously been used to create channel-like structures that can penetrate through lipid bilayer membranes. However, such assemblies have not been shown to cause cell death before. Now a DNA nanopore has been shown to exert a cytotoxic effect when administered to cells.

Energy storage using batteries offers a solution to the intermittent nature of energy production from renewable sources; however, such technology must be sustainable. This Review discusses battery development from a sustainability perspective, considering the energy and environmental costs of state-of-the-art Li-ion batteries and the design of new systems beyond Li-ion. Images: batteries, car, globe: © iStock/Thinkstock.

Peptides that self-assemble into nanostructures are of interest for many applications, including ones relevant to cosmetics, food, biomedicine and nanotechnology. Now, computational tools have been developed that enable peptide sequence space to be rapidly searched for supramolecular properties and this approach has been used to identify unprotected tripeptide hydrogelators.

Amines are essential in a number of research areas, but a general, selective and step-efficient synthesis has been elusive. Now, the use of a single copper catalyst to transform alkynes into enamines, α-chiral branched alkylamines, and linear alkylamines is described. These transformations have been applied in the preparation of a selection of current pharmaceutical agents.

Modifying or functionalizing transition metal dichalcogenides (TMDs) allows their properties to be altered and controlled. Now, non-defect-mediated covalent functionalization of single-layer semiconducting TMDs such as MoS₂, WS₂ and MoSe₂ has been demonstrated by reacting them with organohalides, utilizing the excess charge in the 1T metallic phase.

The maximum attainable capacity of the Li–O₂ battery is limited by the passivation of its cathode by electronically insulating Li₂O₂. It is now shown that electrolyte additives, which activate solution-mediated growth of Li₂O₂, make it possible to circumvent this fundamental limitation, leading to design rules for additive selection.

The stereochemical outcome of enzyme-catalysed reactions with physiological substrates is typically governed by the well-defined geometry of the enzyme active site. Now, a rare example is reported where the substrate controls the stereoselectivity of a Michael-type addition during lanthipeptide biosynthesis.

Crystals of hexachlorobenzene easily break when pressed on the (100) face, but bend to 360° without disintegrating when stress is applied on the (001) face. In the latter case this extraordinary malleability arises from the segregation and sliding of layers of molecules in the crystal, a process in which halogen–halogen interactions are broken and reformed.

A method for rapidly screening small-molecule inhibitors of amyloid assembly has been developed. This method uses electrospray ionization–ion mobility spectrometry–mass spectrometry to detect and identify the type of inhibition. A screen of this nature could help in the discovery of therapeutics for numerous diseases associated with aberrant protein aggregation.

The pseudopterosins are a family of natural products whose interesting anti-inflammatory and pain-relieving properties have inspired many synthetic approaches. Now, an unusual approach that starts with an axially chiral hydrocarbon that engages in a triple Diels–Alder sequence has been shown to result in the shortest total synthesis of a pseudopterosin so far.

Claire Hansell surveys the uses, past and present, for antimony, including an unusual method for 'recycling' it.