Reviews & Analysis

Site-specific modification of RNA in cells is crucial for analysis and functional investigations. Natural enzymes that promote RNA methylation using S-adenosyl-l-methionine (SAM) exist, but leveraging these proteins for RNA modification is limited by cell permeability, stability and specificity of their substrates. Now, a de novo ribozyme that acts on a stabilized and cell-permeable SAM analogue enables site-specific RNA modification with a click handle in living cells.

Fluorination strategies are important in assisting the synthesis of pharmaceuticals. Iodine(I/III) catalysis has become particularly useful for installing gem-difluoro groups but is limited to styrenes. Now, the hypervalent iodane-catalysed difluorination of enynes has enabled access to diverse homopropargylic difluorides.

Organic chemists meet biennially to present exciting developments in the realm of synthesis. Thomas Barber discusses the standout themes of this year’s international synthesis in organic chemistry symposium.

Gas bubble accumulation at interfaces is a barrier to achieving more efficient electrochemical devices. A clever model system to understand bubble formation during electrochemical hydrogen evolution now reveals similarities between the forces at play during their detachment from the catalyst surface and those involved in wine climbing up a glass.

Aromatic oligoamide macrocycles have been developed in which the constrained backbone enforces hydrogen-bond donors to orient towards the macrocycle centre, forming a highly electropositive cavity. These macrocycles show strong binding for various anions and can partition into biomembranes to facilitate selective transmembrane anion transport.

The factors that control the solubility of a salt are many and varied. Now a set of salts with closely related cations suggests that weak London dispersion-controlled CH···π interactions can dominate solubility, despite the presence of much stronger forces.

The intentional interweaving of two different metal–organic framework (MOF) lattices could offer a strategy for combining the disparate properties of the two frameworks within a single MOF material. Now, the rational construction of such hetero-interpenetrated MOFs has been demonstrated.

Light is a major driver of the chemistry of the atmosphere and usually involves the photolytic fragmentation of molecules into radicals before their reaction. New results show that formaldehyde, excited by low-energy light, can react with oxygen, opening up alternative atmospheric oxidation pathways.

An infrared laser-induced temperature jump provides a rapid and broadly applicable perturbation to protein dynamics. Temperature-jump crystallography was paired with time-resolved X-ray crystallography to study the dynamic enzyme lysozyme. Measurements with and without a functional inhibitor revealed different patterns in the propagation of motion throughout the enzyme.

Experimental and computational studies establish the operation of Fe(iii)-based metalloradical catalysis for the asymmetric cyclopropanation of alkenes with different classes of diazo compounds. The reaction proceeds through a stepwise radical mechanism involving α-Fe(iv)-alkyl and γ-Fe(iv)-alkyl radical intermediates. This work provides a future direction for the development of metalloradical catalysis.

Deuterated compounds are used in many applications such as mass-spectrometry standards, drugs or in organic light-emitting diodes. Now, hydrogen-activated homogeneous pincer complex catalysts can be used to perform selective alkene deuteration with the cheapest available deuterium source, D₂O.

Aryl ethers are useful intermediates in organic synthesis and are found in countless biologically active compounds. Now, through palladium/norbornene cooperative catalysis and incorporation of a polarity-reversed N–O reagent as the O-electrophile, an efficient arene methoxylation approach has been successfully developed.

Medicinal chemistry efforts typically focus on drug–protein interactions and overlook RNA binding as a source of off-target pharmacology. Now, a new method has been developed to map the interactions of small-molecule drugs with RNA in cells and characterize how these interactions can exert functional effects.

Radiation damage in biological systems by radicals and low-energy electrons formed from water ionization is a consequence of ultrafast processes that follow core-level ionization of hydrated metal ions. More details of the complex pathway are now revealed from the study of aluminium-ion relaxation through sequential electron-transfer-mediated decay.

Plants produce a wide range of compounds with important bioactivities. Celastrol, an anti-obesity agent found in the root of certain plants, can now be produced de novo in yeast.

When atoms first appeared in the Universe, molecules were needed to help coalesce them into stars. The trihydrogen cation H₃⁺ is among the prime candidates for that process, and now two independent studies provide detailed insight into the ultrafast dynamics of the formation of this important ion from two hydrogen molecules.

Although Li–O₂ batteries offer high theoretical energy storage capacities, few approach these limits. Now, a class of redox mediators is shown to send the discharge reaction from the electrode surface into the electrolyte solution, boosting device capacities and providing selection criteria for future efforts.

Scientists have been studying how polymers break in solutions for decades, but the mechanism by which chains are stretched to the point of covalent bond scission is not trivial. Now, an experiment series provides ample support for a dynamic model in which chains uncoil from end to middle, while concurrently relaxing.

Although light-driven conversion of carbon dioxide receives widespread attention, it is also criticized due to the challenge of discerning true product formation from that of impurities. Now, significantly advanced guidelines for proper product identification have been developed, so we can better trust in what we see.

A multimodal imaging approach is developed to interrogate microorganism–semiconductor biohybrids at the single-cell and single-molecule level for light-driven CO₂ fixation. Application to lithoautotrophic bacterium Ralstonia eutropha biohybrids reveals the roles of two hydrogenases in electron transport and bioplastic formation, the magnitude of semiconductor-to-single-cell electron transport and the associated pathways.