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  • Lignin-derived phenolic acids can be upgraded to styrene derivatives through chemoenzymatic processes, however, the scale-up of such processes remains challenging. Here, the authors find that controlling the water activity during the decarboxylation of bio-based phenolic acids, including through the integration of a water reservoir, enables high conversions and efficient reaction times, that can be combined with a versatile acyl donor substrate scope.

    • Philipp Petermeier
    • Jan Philipp Bittner
    • Selin Kara
    ArticleOpen Access
  • Carbocations are highly electrophilic intermediates involved in SN1 reactions, such as the direct alkylation of low-reactivity nucleophiles, however, in situ activation of leaving groups in such reactions remains challenging due to the unstable nature of the carbocations, leading to cross-reactivity between nucleophiles and leaving group activators. Here, the authors develop a two-step procedure to avoid such cross-reactivity: they generate carbocationoids as coordinatively stabilized carbocations in one nucleophile-free solution, and then complete the alkylation in another reaction vessel under mild conditions.

    • Hikaru Fujita
    • Daichi Shimada
    • Munetaka Kunishima
    ArticleOpen Access
  • Retention time prediction in liquid chromatography plays an important role in molecule annotation and method optimization, however, the accuracy of current quantitative structure−retention relationship models highly depends on the chromatographic method (CM). Here, the authors develop a generic model featuring a post-projection calibration to eliminate the impact of specific CMs, reaching similar ranking levels of putative candidates among different CMs.

    • Yan Zhang
    • Fei Liu
    • Qing He Zhang
    ArticleOpen Access
  • Computer-aided retrosynthetic planning algorithms such as Monte Carlo Tree Search (MCTS) and A* search can expedite the identification of synthetic pathways, however, achieving a high success rate remains challenging. Here, the authors develop an enhanced search algorithm by incorporating the exploration capability of MCTS into A* search, achieving synthesis success rates of up to 100%.

    • Dengwei Zhao
    • Shikui Tu
    • Lei Xu
    ArticleOpen Access
  • The effective control of chirality on surfaces is crucial for applications such as enantioselective heterogeneous catalysis and nonlinear optics. Here, the authors study the on-surface synthesis of organometallic polymers and their chiral expression on Ag(110), demonstrating that kinetic effects play an important role in determining polymer chirality.

    • R. S. Koen Houtsma
    • Floris van Nyendaal
    • Meike Stöhr
    ArticleOpen Access
  • CO2 electrolyzers with gas diffusion electrodes take advantage of improved mass transport of gaseous CO2 to the catalyst surface to afford increased current densities, but the complex and coupled multi-phase processes occurring inside the electrolysis device are not fully understood. Here, the authors use a two-dimensional volume-averaged model of the cathode side of a microfluidic CO2 to CO electrolysis device with a gas diffusion electrode and find that under high cathodic potential, the catalyst layer is prone to forming H2 and CO bubbles, mirroring observed experimental electrode instability.

    • Venu Gopal Agarwal
    • Sophia Haussener
    ArticleOpen Access
  • Fluorescence-based oligonucleotide probes, also known as molecular beacons (MBs), are popular for detecting nucleic acids with high specificity. Here, the authors demonstrate self-sequestration of MB-based biosensors and target strands within peptide-based coacervates, increasing local concentrations and significantly increasing the sensitivity and kinetics of the DNA biosensors.

    • Christopher M. Green
    • Deborah Sementa
    • Sebastián A. Díaz
    ArticleOpen Access
  • Ipatasertib is a potent Akt (protein kinase B) inhibitor synthesized via a chemoenzymatic process. Here, the authors use mutational scanning and algorithm-aided enzyme engineering to optimize a ketoreductase from Sporidiobolus salmonicolor and generate a 10-amino acid substituted variant exhibiting a 64-fold higher kcat and improved yield for the relevant alcohol intermediate, with ≥ 98% conversion and a diastereomeric excess of 99.7% (R,R-trans) from 100 g L−1 ketone after 30 h.

    • Sumire Honda Malca
    • Nadine Duss
    • Rebecca Buller
    ArticleOpen Access
  • African swine fever virus type II DNA topoisomerase (AsfvTop2) is known to change DNA topology by employing a complex catalytic cycle and is involved in the early stages of viral gene replication, however, the structural and regulatory functions of AsfvTop2 remain underexplored. Here, the authors use cryo-EM to demonstrate six conformers of apo-AsfvTop2 as well as the structures of AsfvTop2-DNA-inhibitor complexes, revealing experimental evidence of their substrate binding mechanism that also shed light to other enzymes.

    • Chiung-Wen Mary Chang
    • Shun-Chang Wang
    • Ming-Daw Tsai
    ArticleOpen Access
  • The effects of co-solutes on protein solubility, stability and function have been well studied, however, some of the theories appear inconsistent and no clear theoretical framework has been established. Here, the authors investigate the NMR titrations of protein barnase with Hofmeister ions and osmolytes to distinguish binding effects from solvent perturbation and provide a coherent explanation for solute effects.

    • Clare R. Trevitt
    • D. R. Yashwanth Kumar
    • Mike P. Williamson
    ArticleOpen Access
  • Dual-controlled molecular release is of importance in the construction of controlled delivery systems with high anti-interference capabilities, but has been underexplored in the context of guest release from supramolecular entities. Here, the authors report a coordination cage whereby changes in both the coordinative metal cation and the solvent system are needed to induce guest release.

    • Yuqing Yao
    • Chengyuan Shao
    • Ying Wang
    ArticleOpen Access
  • The atomically precise on-surface synthesis of carbon-based nanostructures is of relevance for electronic and optoelectronic devices, but achieving control over such architectures remains challenging. Here, the authors demonstrate the selective stepwise on-surface synthesis of nitrogen-doped porous carbon nanoribbons with well-defined topologies and structures, and predict variable band gaps dependent on ribbon width.

    • Jin Xu
    • Shuaipeng Xing
    • Ziliang Shi
    ArticleOpen Access
  • Sorbicillactone A is a nitrogen-containing sorbicillinoid that displays various bioactivities, identified from a sponge-derived Penicillium chrysogenum strain. The first and so far obly total synthesis of sorbicillactone A led to the racemate in 12 linear steps and a 0.13% overall yield. Here, the authors develop a chemoenzymatic stereoselective total synthesis of sorbicillactone A in 4 steps and 11% yield by using the enzyme SorbC for the enantioselective oxidative dearomatization of sorbillin to sorbicillinol followed by addition of an azlactone unit.

    • Jonas I. Müller
    • Tobias A. M. Gulder
    ArticleOpen Access
  • Although depolymerization methods for various commodity plastics and several engineering plastics have been developed, such methods for robust super engineering plastics that have very high heat and chemical resistance are nearly unexplored. Here, the authors report the catalytic depolymerization-like chemical decomposition of oxyphenylene-based super engineering plastics such as polyetheretherketone, polysulfone, and polyetherimide using thiols via selective carbon–oxygen main chain cleavage to form monomer-type molecules, namely electron-deficient arenes with sulfur functional groups and bisphenols.

    • Yasunori Minami
    • Sae Imamura
    • Masaru Yoshida
    ArticleOpen Access
  • Recently, a medium-density amorphous ice (MDA) was synthesized via ball-milling of hexagonal ice, adding complexity to our understanding of the phase diagram of supercooled water and amorphous ice. Here, the authors use molecular dynamics simulations to show that, depending on the employed pressure, isobaric cooling can generate a continuum of amorphous ices with densities that expand in between those of low- and high-density amorphous ices, with some of these amorphous ices being remarkably similar to MDA.

    • Ali Eltareb
    • Gustavo E. Lopez
    • Nicolas Giovambattista
    ArticleOpen Access
  • Bivalent molecules comprising dual functional motifs often exhibit strong target binding, however arriving at the optimal structure is challenging. Here, the authors employ EGFR as a model system for understanding a subtle difference in the linker structure of bivalent inhibitors to enhance binding against drug-resistant EGFR mutants.

    • Florian Wittlinger
    • Blessing C. Ogboo
    • David E. Heppner
    ArticleOpen Access
  • Ultraprecise spectral line lists of molecules such as water, omnipresent in various environments, can be used to calibrate high-resolution spectra, which is particularly relevant for exoplanet transit observations. Here, the authors use measured spectra and network theory to achieve ultraprecise characterization of H216O and H218O hubs, the most relevant quantum states within a spectroscopic network.

    • Roland Tóbiás
    • Meissa L. Diouf
    • Attila G. Császár
    ArticleOpen Access
  • Electronic energy transfer (EET) between chromophores is a critical process for solar energy funneling, and recent studies using scanning tunneling microscopy have shown that chromophores deposited on solid substrates in such conditions display peculiar EET features. Here, hybrid ab initio and electromagnetic modeling provide a comprehensive theoretical analysis of tip-enhanced EET.

    • Colin V. Coane
    • Marco Romanelli
    • Stefano Corni
    ArticleOpen Access
  • Nickel organic compounds play a crucial role in organic and bioinorganic chemistry, however, their potential role in prebiotic chemistry is not well understood. Here, the authors identify the formation of a nickel bis(dithiolene) from nickel sulfide under an acetylene-containing volcanic hydrothermal experimental environment and reveal its role in the transformation of acetylene to acetaldehyde.

    • Philippe Diederich
    • Christian Seitz
    • Philippe Schmitt-Kopplin
    ArticleOpen Access
  • Covalent probes are a powerful tool for investigating small molecule and protein interactions, however, the development of reactive warheads to form covalent probes remains underexplored. Here, the authors develop α-acyloxyenamide electrophiles to covalently bind to lysine residues, and selectively profile the conserved lysine residues of kinase in live cells.

    • Yuanyuan Zhao
    • Kang Duan
    • Zhengqiu Li
    ArticleOpen Access