Articles in 2023

A nanopore framework has been developed to reveal the crosstalk effect on the renin–angiotensin system. By reading the single-amino-acid differences in angiotensin peptides with high accuracy and high efficiency, the selective inhibition of angiotensin-converting enzyme by angiotensin-converting enzyme 2 was revealed. This activity was shown to be suppressed by the spike protein of SARS-CoV-2.

Organolithium compounds are important reagents but are often hazardous due to their high reactivity. Now, encapsulating organolithium reagents within a supramolecular organogel has been found to enhance their stability, facilitating their storage and handling under ambient conditions. The homogeneous gels can be easily subdivided and dosed into a wide range of synthetic reactions.

Substituted bicyclo[2.1.1]hexanes (BCHs) are emerging bicyclic hydrocarbon bioisosteres for ortho- and meta-substituted benzenes, but are difficult to access. Now a SmI₂-catalysed intermolecular coupling of bicyclo[1.1.0]butyl ketones and alkenes provides a general approach to access substituted BCHs, thus promoting their widespread use in medicinal chemistry and crop science.

Sorbent materials that reversibly transform between closed (non-porous) and open (porous) phases on the uptake and release of guests are relevant to gas storage and separation applications. Now, a coordination network has been prepared that exhibits gas-induced transformations between multiple non-porous phases. This phenomenon is attributed to subtle structural rearrangements that enable transient porosity.

The advantages and disadvantages of building a nanosystem using one, two or more molecular components are poorly understood. Now, using structural and catalytic DNA-based nanosystems and theoretical simulations, it has been shown that the assembly of trimeric nanosystems displays much higher levels of programmability and functionality than the monomeric or dimeric counterparts.

X-ray diffraction is crucial for the phase elucidation of polycrystalline materials but remains challenging for complex multiphase systems. Now serial rotation electron diffraction has been shown to enable rapid, reliable and semiquantitative phase analysis of such systems, facilitating high-throughput screening of complex synthesis systems and providing new opportunities for materials development.

Neutral homoaromatic hydrocarbons—which possess an interrupted π-system yet display aromatic properties owing to through-space or through-bond interactions—have remained rare as they are typically unstable. Now a class of stable neutral homoaromatic homoannulenes has been synthesized, including one that acts as a photoswitch through a reversible [1, 11] sigmatropic rearrangement.

Current strategies for photoinduced olefin metathesis lack wavelength tunability. Now, plasmonic nanoparticles have been used to activate latent ruthenium catalysts, enabling light-induced olefin metathesis in the infrared range with several advantages when compared with conventional heating. Implementing this approach in ring-opening metathesis polymerization resulted in photoresponsive polymer–nanoparticle composites with enhanced mechanical properties.

Mechanochemical generation of dyes with different photophysical properties generally requires the use of discrete mechanophore derivatives with unique chemical structures. Now it has been shown that diverse donor–acceptor Stenhouse adducts can be produced via a mechanically gated chromogenic reaction, enabling mechanochemical multicolour lithography.

Cycloaddition reactions are among the most useful reactions in chemical synthesis, but biosynthetic enzymes with 2 + 2 cyclase activity have yet to be observed. Now it is shown that a β-barrel-fold protein catalyses competitive 2 + 2 and 4 + 2 cycloaddition reactions. This protein can be engineered to preferentially produce the exo-2 + 2, exo-4 + 2 or endo-4 + 2 product.

The direct conversion of sulfones to chiral sulfinyl compounds is one of the major challenges in the fields of asymmetric synthesis and organosulfur chemistry. Now, through incorporation of a cyano group into the sulfone, an organocatalytic asymmetric deoxygenation strategy has been developed that enables the synthesis of chiral sulfinyl compounds.

An active-template approach has been used to prepare π-conjugated interlocked nanocarbons derived from [n]cycloparaphenylenes. A metal ion bound within the central cavity of a precursor macrocycle first catalyses cross-coupling reactions and then the resulting mechanically interlocked intermediates are further transformed into π-conjugated species—[2] and [3]catenanes as well as a conjugated [3]rotaxane.

A Diels–Alderase that catalyses the inherently disfavoured cycloaddition and forms a bicyclo[2.2.2]diazaoctane scaffold with a strict α-anti-selectivity has now been discovered. This Diels–Alderase, called CtdP, is an NmrA-like protein. Isotopic labelling, structural biology and computational studies reveal that the CtdP-catalysed Diels–Alder reaction involves a NADP⁺/NADPH-dependent redox mechanism.

Controlling various selectivities in radical reactions presents both formidable challenges and great opportunities. Now, Co(II)-based metalloradical catalysis has enabled the concurrent control of multiple convergences and selectivities in intermolecular radical allylic C−H amination. The reaction provides access to valuable chiral α-tertiary amines directly from an isomeric mixture of alkenes.

The complementarity of the two strands in the DNA double helix provides a mechanism for the storage and processing of genetic information. Now, an alternative ‘strand commutation’ mechanism of data processing with DNA/RNA has been revealed based on the reversible low-affinity interactions of essentially non-complementary nucleic acids.