Articles

Single crystals of a helical covalent polymer have been obtained from an achiral monomer through spiroborate formation. Polymerization and crystallization occur simultaneously to give a network of pairs of entwined helical strands of the same handedness. No strong non-covalent interactions were observed between the two helical polymers forming a pair; instead, each interacts with neighbouring pairs through hydrogen bonding.

Although diazoalkenes have been reported as reactive intermediates in organic chemistry, their detection and isolation remains challenging. Such species have previously only been detected at low temperatures in matrix-isolation studies. Now, a room-temperature stable diazoalkene has been reported, which shows dual-site nucleophilicity and can undergo N₂ exchange or lose dinitrogen under irradiation.

In atomic solids, substitutional doping is a powerful approach to modulating materials properties. Now, three substitutional mixtures of {Co₆Se₈} and {Cr₆Te₈} clusters in a crystal lattice with C₆₀ fullerenes have been prepared. At two Co:Cr mixing ratios, the solid solutions showed particularly high electrical conductivities and low activation barriers for electron transport, owing to their structural heterogeneity.

Although strategies for the automated assembly of compounds of pharmaceutical relevance is a growing field of research, the synthesis of small-molecule pharmacophores remains a predominantly manual process. Now, an automated six-step synthesis of prexasertib is achieved by multistep solid-phase chemistry in a continuous-flow fashion using a chemical recipe file that enables automated scaffold modification through both early and late-stage diversification.

Robust delivery of proteins into cells is challenging, but it has now been shown that by conjugating arginine-rich cell-penetrating peptides to the surface of cells, proteins containing a cell-penetrating peptide can be delivered efficiently into them. Using a thiol-reactive cell-penetrating peptide enables thiol-containing proteins to be delivered by simple co-incubation.

The development of metal–organic magnets that combine tunable magnetic properties with other desirable physical properties remains challenging despite numerous potential applications. Now, a mixed-valent chromium–triazolate material has been prepared that exhibits itinerant ferromagnetism with a magnetic ordering temperature of 225 K, a high conductivity and large negative magnetoresistance (23%).

Voltage imaging is a powerful technique for studying electrical signalling in neurons. A palette of bright and sensitive voltage indicators has now been developed via enzyme-mediated ligation and Diels–Alder cycloaddition. Among these, a far-red indicator faithfully reports neuronal action potential dynamics with an excitation spectrum orthogonal to optogenetic actuators and green/red-emitting biosensors.

A supramolecular three-shell matryoshka-like complex di rects the functionalization of the C₆₀ inner shell to the selective formation of a single trans-3 fullerene bis-adduct. The selectivity with this matryoshka-like approach could be useful for applications where regioisomerically pure C₆₀ bis-adducts have been shown to have superior properties compared with isomer mixtures.

The assembly of a single configuration of an all-carbon quaternary centre within acyclic systems remains a challenge for synthetic chemists. Now, it has been shown that α-all-carbon quaternary centres can be installed in acyclic amides, with excellent levels of absolute stereocontrol, through a radical sulfinyl Truce–Smiles rearrangement.

A DNA-encoded chemical library based on regio- and stereoisomers of phenylalanine has been synthesized and used for affinity-based selections against multiple target proteins. This approach led to the isolation and validation of potent ligands capable of CAR T-cell activation and tumour targeting.

The overall efficiency of free-triplet generation from intramolecular singlet fission is limited by the efficiency of the dissociation of spatially adjacent triplet pairs. Now, using transient magneto-optical spectroscopy, it has been shown that this limitation can be overcome by promoting a pathway mediated by spatially separated triplet pairs in tetracene trimers and tetramers.

State-of-the-art industrial methods for transforming P₄ into useful phosphorus compounds currently rely on indirect, multi-step strategies. It has now been shown that straightforward one-pot reactions can convert P₄ directly into industrially relevant products while requiring only mild conditions and simple, inexpensive reagents—and can also functionalize P₄ catalytically.

DNA G-quadruplexes can adopt a variety of secondary structures, but it is challenging to identify and classify them quickly. Multivariate analysis of different fluorescence enhancements—generated from an arrayed suite of synthetic hosts and cationic dyes—enables discrimination between G-quadruplex structures of identical length and similar topological types.

Small liposomes of uniform sizes are valuable tools for studying membrane biology and developing drug-delivery vehicles. Now, a DNA-assisted sorting technique has been shown to produce multiple species of monodispersed liposomes with mean diameters below 150 nm in a scalable manner. This approach has enabled the high-resolution analyses of curvature-dependent membrane protein activities.

On-surface dehydrogenative bond formation between sp³-hybridized carbon atoms usually requires high temperatures. Now, it has been shown that the higher homologue, silicon, can undergo dehydrogenative polymerization at room temperature on metal surfaces. This process creates well-ordered structures on Au(111) and Cu(111), with different stereoselectivity depending on the metal.

O-methyl nitronate is a rare functional group in natural products. Now, the biosynthetic pathway to O-methyl nitronate, which involves O-methylation of a peptidyl carrier protein (PCP)-tethered nitronate, has been revealed. In some bacteria, the same PCP-tethered nitronate is shown to be oxidized by nitronate monooxygenases to provide nitrite and a PCP-tethered glyoxylate.

RNA-cleaving DNA enzymes (DNAzymes) have the potential to function as therapeutic agents by silencing the expression of disease-associated proteins. Xeno-nucleic acids were used to improve the catalytic activity and biological stability of a highly evolved DNAzyme known as 10–23. The enzyme exhibits a robust multiple-turnover activity in cultured mammalian cells.

Molecular catalysts can be made more practical by anchoring them onto electrode surfaces, but such systems are less stable than standard heterogeneous electrocatalysts. Now, supramolecular hosts bound to electrode surfaces have enabled the immobilization of molecular electrocatalysts through host–guest interactions. Desorbed or degraded guest molecules can be replaced with fresh guest molecules, extending their lifetimes.

Excising hydrogen adjacent to a carbonyl group—one of the most basic and widely employed transformations in organic synthesis—is traditionally achieved using metals and/or stoichiometric oxidants. Now, it has been shown that an electrochemically driven approach removes such requirements, resulting in a more sustainable and easily scalable method with wide substrate scope.

Although many natural products and drug molecules contain N–N linkages, the chemistry of N–N coupling is somewhat underdeveloped. Now, a nitrene-mediated intermolecular N–N coupling of dioxazolones and arylamines that relies on iridium or iron catalysis has been developed. These reactions offer a simple and efficient method for the synthesis of hydrazides from readily available precursors.