Reviews & Analysis

Molecules containing a chiral S(VI) moiety have found extensive applications in drug design and organic synthesis, despite a lack of diverse asymmetric methods for their creation. Now, a ligand-mediated process has enabled the production of enantioenriched S(VI)–F motifs, providing a foundation for further stereospecific elaborations.

A protein-templated selection approach has been developed for the discovery of full ligands from dual-pharmacophore DNA-encoded libraries by incorporating fragment linking into the selection process. The performance of this method was demonstrated with selections against protein–protein interaction and protein–DNA interaction targets, through which potent and selective inhibitors were identified.

Dinitrogen (N₂) fixation to ammonia (NH₃) is typically challenging under mild conditions. Now, lithium hydride (LiH) is shown to mediate photodriven N₂ fixation under ambient conditions. Under ultraviolet illumination, LiH is photolysed to release H₂, leaving electrons residing in surface hydrogen vacancies, which facilitate N₂ activation and photocatalytic NH₃ synthesis.

Cryptic halogenation reactions result in natural products with diverse structural motifs and bioactivities. However, these halogenated species are difficult to detect with current analytical methods because the final products are often not halogenated. An approach to identify products of cryptic halogenation using halide depletion has now been discovered, opening up space for more effective natural product discovery.

Interlocking unstable motifs is a useful way to enhance their stability through shielding protection. Now, stable interlocked polyynes bearing several macrocycles have been prepared, including a [5]rotaxane having 34 contiguous alkynes with properties similar to those of carbyne.

Despite the growing clinical use of radium in cancer treatments, the fundamental chemistry of nature’s largest +2 cation remains largely unexplored. Now, structural analysis of a radium complex reveals that its behaviour cannot always be predicted from the chemistry of its closest nonradioactive congener, barium.

Directional interactions and three-dimensional functional groups are crucial to medicinal compounds. Consequently, new functional groups require stereocontrolled synthetic methods. Now, an enantiopure building block provides controlled and divergent access to valuable sulfonimidoyl functional groups.

Trans–cis photoisomerization is a fundamental photochemical reaction that is thought to proceed through an intermediate with a perpendicular conformation. However, unambiguous identification of this state has proved challenging. The combination of state-of-the-art ultrafast spectroscopy and quantum chemical calculations now provides evidence for its structural observation in stilbene photoisomerization.

Tetracoordinate boron molecules are the key intermediates in many organoboron-related chemical transformations. Now, using alkynyl tetracoordinate boron species, a nickel-catalysed asymmetric 1,3-metallate shift towards axial chirality has been developed, giving access to various axially chiral alkenes in high efficiency.

The self-assembly of stimuli-responsive building blocks yields functional nano-systems and smart materials. This Perspective discusses how the integration of photoswitches into discrete coordination cages enables control over their assembly, guest binding and systems behaviour. Four scenarios are drawn to highlight the relationship between the photoswitching and dynamic assembly equilibria.

Liquid–liquid phase separation (LLPS) within cells is a captivating phenomenon known to aid the organization of cellular components; however, its complex kinetics have remained a puzzle. Now, a new study elucidates the crosstalk between the phase state of an encapsulating membrane and LLPS dynamics.

As the need for specific fluorescent probes that enable high sensitivity and super-resolution imaging experiments continues to grow, it is imperative to develop new, well-characterized methods to modulate the emission of fluorophores. Now, a general platform affords visible-to-NIR fluorogenic fluorophores by engineering a simple cyclization event into cyanine dyes.

The study of disordered materials poses numerous challenges, and computational approaches have proved useful to supplement and support structural experiments. Now, an abstract computational model has been used to study the structure of amorphous calcium carbonate, providing mechanistic insights into the emergence of the disordered phase as well as its atomic-level configurations.

Fluoroalkyl fragments are ubiquitous motifs in pharmaceuticals and agrochemicals, but their introduction to a given molecule typically involves expensive or difficult-to-handle reagents. Now, the photocatalysed hydrofluoroalkylation of alkenes has been achieved using simple and readily available fluoroalkyl carboxylic acids.

Stereoselective decarboxylative protonation can produce diverse chiral molecules from widely available carboxylic acids. However, general and practical strategies are lacking. Now, a chiral spirocyclic phosphoric acid-catalysed decarboxylation of aminomalonic acids has enabled the modular synthesis of α-amino acids.

Recent improvements in de novo protein design are likely to support a broad range of applications, but larger complexes will be easier to create if a building block approach is adopted. Now protein filaments with tunable geometry can be made using assemblies that have both cyclic and superhelical symmetries aligned along the same axis.

Ribonucleoprotein granules are ubiquitous in living organisms with the protein and RNA components having distinct roles. In the absence of proteins, RNAs are shown to undergo phase separation upon heating. This transition is driven by desolvation entropy and ion-mediated crosslinking and is tuned by the chemical specificity of the RNA nucleobases.

To develop covalent inhibitors with high potency and low off-target effects, combinatorial approaches that search for candidates from large libraries are desired. Here, sulfur(VI) fluoride exchange (SuFEx) in vitro selection is established for the evolution of covalent aptamers from trillions of SuFEx-modified oligonucleotides. Through this technique, covalent aptamers with optimally balanced selectivity and reactivity are identified.