Research articles

The development of molecules that target protein–protein interactions is one of the main goals of contemporary medicinal chemistry. Computational alanine scanning and molecular dynamics now leads to the identification of two peptide sequences that are important in microtubule assembly, and shows that the in silico activity can be translated into in vitro activity.

The properties of surfaces can be tailored by coating them with a thin film of molecules, for example by forming self-assembled monolayers. Now, researchers have shown how dynamic covalent chemistry can be used to reversibly pattern different compounds on to a surface with a high degree of spatial control to produce molecular gradients.

The ability to study structural changes of DNA in live cells is of considerable interest. Here, a dinuclear ruthenium (II) complex that acts as a multifunctional stain for DNA and its use in both luminescence and transmission electron microscopy studies is described.

Plastic solar cells contain a blend of conjugated polymer and fullerene electron-acceptor material that phase separates, resulting in the formation of heterojunctions. Improving the performance of these devices requires an understanding of the blend morphology. Now researchers show how a microwave-assisted synthesis method can be used to create structurally diverse copolymers enabling the investigation of their structure–function relationship.

Materials built from metal centres and organic ligands have traditionally attracted attention for their channels’ host–guest properties. Now, controlling the occupancy of the channels by guest molecules has resulted in a framework that conducts protons under anhydrous conditions and acts as a gas-tight membrane, offering a promising approach to fuel-cell electrolytes.

The properties of molecular electronic devices can be tuned by tailoring the structures of the molecules from which they are built. Researchers now show that two closely related molecules — each containing a string of four aryl groups — behave very differently when strung between gold electrodes, with the non-symmetrical structure leading to diode-like behaviour.

Artificial vesicles consisting of encapsulated fluorescence resonance energy transfer (FRET)-donor molecules and a FRET-acceptor bilayer dye-membrane provide ultrasensitive pH information in aqueous media by displaying pH-dependent fluorescence colour covering the entire visible light range. An exceptional white fluorescence was observed at pH 9.

A ¹⁹F magnetic resonance imaging signal from a protein-specific binding agent can be used to detect the presence of the target protein in live cells. The signal is switched off in the absence of target protein due to aggregation of the probe into nanoclusters.

Improvements in the activity and stability of catalysts for oxygen reduction reactions are needed to make low-temperature, polymer electrolyte membrane fuel-cells viable for mobile applications. Pt₃Sc and Pt₃Y are shown experimentally to have greater catalytic activity than pure Pt after being identified through computational investigation of Pt- and Pd-based alloys.

Compounds containing dioxygen bonded to metal atoms – such as metal-peroxo or -superoxo species – are models of enzymes that can activate oxygen. Now a mononuclear side-on nickel(III)-peroxo complex has been made, which is stabilized by a macrocyclic ligand. The complex can transfer the bound dioxygen to another metal, and conduct nucleophilic reactions.

The cycloaddition of N-metalated azomethine ylides to C₆₀ can result in the formation of a number of different stereoisomeric products. Now, it has been shown that the stereochemical outcome of this reaction can be controlled by carefully choosing the the correct combination of metal and ligand to form the complex that catalyses this process.

Industrial chemicals can pose serious health risks in the workplace, and monitoring them is of vital importance. Researchers now show that an optoelectronic nose based on a colorimetric sensor array of nanoporous pigments can rapidly identify a wide range of toxic gases at their IDLH (immediately dangerous to life or health) concentrations.

A synthesis of 6-deoxyerythronolide B is reported that uses a late-stage C–H oxidative macrocyclization reaction to forge the key macrocyclic core found in the erythromycins. By installing oxygen at a late-stage, this strategy improves synthetic efficiency by minimizing the ‘oxygen load’, and provides stereochemical versatility at the site of oxidation.

H/D exchange reactions in the high vacuum of a mass spectrometer reveal how crown ethers move between ammonium ion binding sites of an oligolysine peptide. This study enables the dynamics of non-covalent interactions to be probed in a unique environment and could be applied to more complex artificial or natural systems.

Protein imbalances in serum can be correlated with disease, but measurement and subsequent diagnosis is made difficult by the complex composition of serum. Now an array-based sensor, containing synthetic gold nanoparticles and biocompatible green fluorescent protein, has been developed that can detect proteins in undiluted human serum at physiologically relevant concentrations.

Single-walled carbon nanotubes wrapped with a carbohydrate-based polymer bearing diaminophenyl groups can be used to detect nitric oxide (NO) — an important messenger molecule for biological signalling. These polymer–nanotube hybrids are capable of real-time and spatially resolved sensing of NO in living cells, and could ultimately prove useful for in vivo detection.

Porous metal–organic frameworks are promising for hydrogen storage applications, but adsorption capacities have remained too low for practical use. Now, the adsorption behaviour of such a framework has been modulated by exchanging cations within its pores resulting in either kinetic trapping or enhanced hydrogen affinity.

Better understanding of the fundamental bonding interactions at electrified metal–liquid interfaces is critical for improving the electrochemical reactions of fuel cells, but now traditional models are shown to be insufficient. Using experimental measurements of various electrocatalytic reactions on platinum and density functional theory it is shown that non-covalent interactions must be considered.

An analysis of key intermediates relevant to gold(I) catalysis has been performed using density functional theory. A bonding model is proposed whereby the reactivity of gold(I)-coordinated carbenes is dependent on carbene substituents and ancillary ligands that dictate where these gold structures lie on a continuum ranging from a metal-stabilized singlet carbene to a metal-coordinated carbocation.

New economic and environmentally benign methods for achieving carbon–carbon bond formation are in constant demand. Here, a remarkably efficient and functional-group-tolerant, metal-free reductive cross-coupling of carbonyl compounds with boronic acids is described.