A rationally designed pH‐activatable fluorescent probe (pHocas‐RIS) has been used to measure localised pH levels in osteocytic lacunae in bone tissue. Conjugation of the moderate bone binding drug risedronate to a pH activatable BODIPY fluorophore enables the probe to penetrate osteocytic lacunae cavities that are embedded deep within the bone matrix. After injection of pHocas‐RIS, any osteocytic lacunae caused by bone‐resorbing osteocytes cause the probe to fluoresce in vivo , thus allowing imaging...
Mon Aug 03, 2020 22:00
The homolytic cleavage of O‒H and N‒H or weak C‒H bonds is a key elementary step in redox catalysis, yet thought to be unfeasible for palladium. In stark contrast, we report the room temperature and reversible oxidative addition of water, isopropanol, hexafluoroisopropanol, phenol, and aniline to a palladium(0) complex with a very labile pyridino ligand thus resembling pervasive N‐heterocyclic carbene (NHC) palladium(II) pre‐catalysts. We elucidate how the oxidative addition of protic solvents or...
Mon Aug 03, 2020 21:24
While the electrochemical nanoimpact technique has recently emerged as a method of studying single entities, its scope is limited by its typical requirement of a catalytically active particle impacting an inert electrode. We show that an active particle–active electrode type scheme can provide valuable mechanistic insight into electrochemical reactions. When an individual Pt electrocatalyst adsorbs to the surface of a partially active electrode, further reduction of electrode‐produced species can...
Mon Aug 03, 2020 20:25
Advances in genomic analyses enable the identification of new proteins that are associated with disease. To validate these targets, tool molecules are required to demonstrate that a ligand can have a disease‐modifying effect. Currently, as tools are reported for only a fraction of the proteome, platforms for ligand discovery are essential to leverage insights from genomic analyses. Fragment screening offers an efficient approach to explore chemical space. We present a fragment screening platform,...
Mon Aug 03, 2020 20:25
Discovering new functional genes, designing perfect crystal structures, and developing high performance materials are the goal being pursued by scientists. Herein, the first antimony pyrophosphate, K2Sb(P2O7)F, possessing an optimal layered structure is reported, where the perfect structure arrangement induces excellent optical properties. K2Sb(P2O7)F not only displays a sharply enhanced birefringence (0.157@546 nm) compared to the existing phosphate optical materials, but also exhibits a strong...
Mon Aug 03, 2020 19:56
Lithium‐oxygen (Li‐O 2 ) batteries are considered as one of the most promising energy storage systems due to their ultra‐high theoretical capacity. However, most currently studied Li‐O 2 batteries are based on the reduction/oxidation of Li 2 O 2 and involve highly reactive superoxide and peroxide species that would cause serious degradation of cathodes, especially carbon‐based materials. It is of great importance to explore lithium‐oxygen reactions and find new Li‐O 2 chemistry which can...
Mon Aug 03, 2020 19:54
The development of concise, sustainable and cost‐effective synthesis of aryltetralin lignans bearing a fused lactone or cyclic ether is of significant medicinal importance. We found that in the presence of Fukuzumi’s acridinium salt under blue LEDs irradiation, functionalized dicinnamyl ether derivatives are converted to aryltetralin cyclic ether lignans with concurrent generation of three stereocenters in good to high yields with up to 20:1 diastereoselectivity. Oxidation of alkene to radical cation...
Mon Aug 03, 2020 18:55
Membrane proteins require lipid bilayers for function. While lipid compositions reach enormous complexities, high‐resolution structures are usually obtained in artificial detergents. To understand whether and how lipids guide membrane protein function, we use single‐molecule FRET to probe the dynamics of DtpA, a member of the proton‐coupled oligopeptide transporter (POT) family, in various lipid environments. We show that detergents trap DtpA in a dynamic ensemble with cytoplasmic opening. Only reconstitutions...
Mon Aug 03, 2020 18:54
Bifunctional catalysis in zeolites possessing both Brønsted and Lewis acid sites offers unique opportunities to tailor shape selectivity and enhance catalyst performance. Here, we examine the impact of framework and extra‐framework gallium species on enriched aromatics production in zeolite ZSM‐5. In this study we compare three distinct methods of preparing Ga‐ZSM‐5 and reveal direct (single step) synthesis leads to optimal catalysts compared to post‐synthesis methods. Using a combination of state‐of‐the‐art...
Mon Aug 03, 2020 17:10
Capability to significantly shorten the synthetic period of a broad spectrum of open organic materials presents an enticing prospect for materials processing and applications. Herein we discovered 1,2,4‐triazolium poly(ionic liquid)s (PILs) could serve as a universal additive to accelerate by at least one order of magnitude the growth rate of representative imine‐linked crystalline open organics, including organic cage, covalent‐organic framework (COF) and macrocycle. This phenomenon results from...
Mon Aug 03, 2020 17:10
The g old‐catalyzed intermolecular oxyarylation of alkene is reported. This work employed the oxidative addition of aryl iodide to Me‐DalphosAu + for the formation of Au(III)‐Ar intermediate. The better binding ability of alkene over O nucleophiles ensured the success of intermolecular oxyarylation, giving desired products with broad substrate scope and high efficiency (>50 examples with up to 95% yield). “One‐pot” converting of methoxy group into other nucleophiles allowed achieving alkene...
Mon Aug 03, 2020 17:10
While many life critical reactions would be infeasibly slow without metal cofactors, a detailed understanding of how protein structure can influence catalytic activity remains elusive. Using de novo designed 3‐stranded coiled coils (TRI and Grand peptides formed using a heptad repeat approach), we examine how the insertion of a three residue discontinuity, known as a stammer insert, directly adjacent to a (His)3 metal binding site alters catalytic activity. The stammer, which locally alters the twist...
Mon Aug 03, 2020 17:08
The wide application of CRISPR‐Cas9 has transformed genome engineering. Nevertheless, the precision to control the tar‐geting activity of Cas9 requires further improvement. Here, we report a toehold switch‐based approach to engineer the conformation of single guide RNA (sgRNA) for programmable activation of Cas9. The activation circuit responsive to multiple inputs can regulate the conformation of sgRNA via toehold switch‐mediated strand displacement reactions. We demonstrate the orthogonal suppression...
Mon Aug 03, 2020 14:25
Herein, we reported the discovery of a redox‐neutral Ni(II) catalytic cycle which is capable of the linear‐selective hydroarylation of unactivated alkenes with arylboronic acids for the first time. This novel catalytic cycle, enabled by the use of electron‐rich diimine ligand, features broad substrate scope, excellent functional group and heterocycle compatibility under mild conditions in the absence of additional oxidants or reductants. Mechanistic investigations using kinetic analysis and deuterium‐labelling...
Mon Aug 03, 2020 13:55
We report a range of highly regioselective openings of [1.1.1]propellane with various allylic zinc halides, as well as zinc enolates of ketones, esters and nitriles. The resulting zincated bicyclopentanes (BCPs) were trapped with a range of electrophiles including acyl chlorides, sulfonothioates, hydroxylamino benzoates, tosyl cyanide as well as aryl and allyl halides, generating highly functionalized BCP‐derivatives. The unusually high regioselectivity of these reactions has been rationalized using...
Mon Aug 03, 2020 12:24
The ligands L1 and L2 form trinuclear self‐assembled complexes with Cu2+ (i.e. [(L1)2Cu3]6+ or [(L2)2Cu3]6+) which both act as a host to a variety of anions. Inclusion of long aliphatic chains on these ligands allows the assemblies to extract anions from aqueous media into organic solvents. Phosphate can be removed from water efficiently and highly selectively even in the presence of other anions.
Sun Aug 02, 2020 22:00
The geometry of reaction compartments can affect the local outcome of interface‐restricted reactions. Giant unilamellar vesicles (GUVs) are commonly used to generate cell‐sized, membrane‐bound reaction compartments, which are, however, always spherical. Here, we have developed a microfluidic chip to trap and reversibly deform GUVs into cigar‐like shapes. When trapping and elongating GUVs that contain the primary protein of the bacterial Z ring, FtsZ, we find that membrane‐bound FtsZ filaments align...
Fri Jul 31, 2020 22:00
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