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The first total synthesis of the Euphorbia diterpenoid pepluacetal is disclosed in both racemic and chiral fashions. The synthesis strategically relies on a photo‐induced Wolff rearrangement/lactonization cascade (WRLC) reaction to access the cyclobutane moiety, a ring‐closing metathesis/cyclopropanation sequence to rapidly forge the 7–3 bicyclic system, and a late‐stage Rh‐catalyzed transannular carbenoid insertion to C(sp3)−H bond followed by a Baeyer–Villiger oxidation and ring‐opening manipulations to install the side chain. The synthetic route demonstrates excellent stereochemical control on the non‐classical concave‐face bond formation, remote traceless stereochemical relay and high scalability to provide 20 mg of (+)‐pepluacetal. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O2) is an exceptional reactive oxygen species in advanced oxidation processes for environmental remediation. Despite single‐atom catalysts (SACs) representing the promising candidate for the selective generation of 1O2 from peroxymonosulfate (PMS), the necessity to meticulously regulate the coordination environment of metal centers poses a significant challenge in the precisely‐controlled synthetic method. Another dilemma to SACs is their high surface free energy, which results in an inherent tendency for the surface migration and aggregation of metal atoms. We here for the first time reported that Ru nanoparticles (NPs) synthesized by the facile pyrolysis method behave as robust Fenton‐like catalysts, outperforming Ru SACs, towards efficient activation of PMS to produce 1O2 with nearly 100 % selectivity, remarkably improving the degradation efficiency for target pollutants. Density functional theory calculations have unveiled that the boosted PMS activation can be attributed to two aspects: (i) enhanced adsorption of PMS molecules onto Ru NPs, and (ii) decreased energy barriers by offering adjacent sites for promoted dimerization of *O intermediates into adsorbed 1O2. This study deepens the current understanding of PMS chemistry, and sheds light on the design and optimization of Fenton‐like catalysts. [ABSTRACT FROM AUTHOR]

Here we report on an ultra‐sensitive colorimetric sensing platform that takes advantage of both the strong amplification power of rolling circle amplification (RCA) and the high efficiency of a simple urease‐mediated litmus test. The presence of a target triggers the RCA reaction, and urease‐labelled DNA can hybridize to the biotinylated RCA products and be immobilized onto streptavidin‐coated magnetic beads. The urease‐laden beads are then used to hydrolyze urea, leading to an increase in pH that can be detected by a simple litmus test. We show this sensing platform can be easily integrated with aptamers for sensing diverse targets via the detection of human thrombin and platelet‐derived growth factor (PDGF) utilizing structure‐switching aptamers as well as SARS‐CoV‐2 in human saliva using a spike‐binding trimeric DNA aptamer. Furthermore, we demonstrate that this colorimetric sensing platform can be integrated into a simple paper‐based device for sensing applications. [ABSTRACT FROM AUTHOR]

Despite the significance of sultines in synthesis, medicine, and materials science, the chemistry of sultines has remained unexplored due to their inaccessibility. Herein, we demonstrate the development of a photoredox‐catalyzed multifluoromethyl radical addition/SO2 incorporation/polar cyclization cascade approach to multifluoromethylated γ‐sultines. The reactions proceed by single electron transfer induced multifluoromethyl radical addition to an alkene followed by SO2 incorporation, and single‐electron reduction for polar 5‐exo‐tet cyclization. Key to the success of the protocol is the use of easily oxidizable multifluoroalkanesulfinates as bifunctional reagents. The reactions proceed with excellent functional‐group tolerance to deliver γ‐sultines in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

Synthetic fluorescent protein chromophores have been reported for their singlet state fluorescence properties and applications in bioimaging, but rarely for the triplet state chemistries. Herein, we enabled their photo‐sensitizing and photo‐crosslinking properties through rational modulations. Extension of molecular conjugation and introduction of heavy atoms promoted the generation of reactive oxygen species. Unlike other photosensitizers, these chromophores selectively photo‐crosslinked aggregated proteins and uncovered the interactome profiles. We also exemplified their general applications in chromophore‐assisted light inactivation, photodynamic therapy and photo induced polymerization. Theoretical calculation, pathway analysis and transient absorption spectroscopy provided mechanistic insights for this triplet state chemistry. Overall, this work expands the function and application of synthetic fluorescent protein chromophores by enabling their triplet excited state properties. [ABSTRACT FROM AUTHOR]

Two‐dimensional fused aromatic networks (2D FANs) have emerged as a highly versatile alternative to holey graphene. The synthesis of 2D FANs with increasingly larger lattice dimensions will enable new application perspectives. However, the synthesis of larger analogues is mostly limited by lack of appropriate monomers and methods. Herein, we describe the synthesis, characterisation and properties of an expanded 2D FAN with 90‐ring hexagons, which exceed the largest 2D FAN lattices reported to date. [ABSTRACT FROM AUTHOR]

The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo‐epoxidation to control the eight‐membered‐ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight‐membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif. [ABSTRACT FROM AUTHOR]

2-Deoxyglycosides, Bromine Radical, Intermolecular Hydroetherification, Photoreaction, Stereoselectivity The rapid constructions of oligosaccharides, 20-mer deoxyglycan, and digoxin are facilitated by a bromide-based hydrogen species through an electron transfer process. Keywords: 2-Deoxyglycosides; Bromine Radical; Intermolecular Hydroetherification; Photoreaction; Stereoselectivity EN 2-Deoxyglycosides Bromine Radical Intermolecular Hydroetherification Photoreaction Stereoselectivity 1 1 1 05/05/22 20220509 NES 220509 B A visible-light-promoted b iterative synthesis of 2-deoxyoligosaccharides is reported by De-Cai Xiong, Xin-Shan Ye, and co-workers in their Research Article (e202114726). [Extracted from the article]