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The use of sequence‐defined digital polymers for data storage and encryption has received increasing attention due to their precision structures similar to natural biomacromolecules (e.g. DNA) but increased stability. However, the rapid development of sequencing techniques raises the concern of information leakage. Herein, dendritic quaternary‐encoded oligourethanes bearing a photoresponsive trigger, self‐immolative backbones, and a mass spectrometry tag of PEG dendron have been developed for data encryption. Although the sequence information in linear analogs can be readily deciphered by mass spectrometry, sequencing of dendritic oligourethanes cannot be achieved by either primary MS or tandem MS/MS owing to the unique spatial conformation. Intriguingly, the fragmentation pathways of a quaternary dendrimer under MS/MS conditions can be converted to 2772‐bit 2D matrices with ≈1.98×1087 permutations, serving as high‐strength encryption keys for highly reliable data encryption. [ABSTRACT FROM AUTHOR]

Ligand coupling on hypervalent main group elements has emerged as a pivotal methodology for the synthesis of functionalized N‐heteroaromatic compounds in recent years due to the avoidance of transition metals and the mildness of the reaction conditions. In this direction, the reaction of N‐heteroaryl sulfur(IV) and N‐heteroaryl phosphorus(V) compounds has been well studied. However, the ligand coupling of sulfur(VI) is still underdeveloped and the reaction of alkyl N‐heteroarylsulfones is still elusive, which does not match the high status of sulfones as the chemical chameleons in organic synthesis. Here we present a ligand coupling‐enabled formal SO2 extrusion of fluoroalkyl 2‐azaheteroarylsulfones under the promotion of Grignard reagents, which not only enriches the chemistry of sulfones, but also provides a novel and practical synthetic tool towards N‐heteroaromatic fluoroalkylation. [ABSTRACT FROM AUTHOR]

A mild and convenient method for the synthesis of reverse glycosyl fluorides (RGFs) has been developed that is based on the silver‐promoted radical dehydroxymethylative fluorination of carbohydrates. A salient feature of the reaction is that furanoid and pyranoid carbohydrates furnish structurally diverse RGFs bearing a wide variety of functional groups in good to excellent yields. Intramolecular hydrogen atom transfer experiments revealed that the reaction involves an underexploited radical fluorination that proceeds via β‐fragmentation of sugar‐derived primary alkoxyl radicals. Structurally divergent RGFs were obtained by catalytic C−F bond activation, and our method thus offers a concise and efficient strategy for the synthesis of reverse glycosides by late‐stage diversification of RGFs. The potential of this method is showcased by the preparation and diversification of sotagliflozin, leading to the discovery of a promising SGLT2 inhibitor candidate. [ABSTRACT FROM AUTHOR]

Three‐dimensionally (3D) well‐ordered and highly integrated graphene hybrid architectures are considered to be next‐generation multifunctional graphene materials but still remain elusive. Here, we report the first realization of unprecedented 3D‐patterned graphene nano‐ensembles composed of a graphene monolayer, a tailor‐made structured organophenyl layer, and three metal oxide films, providing the first example of such a hybrid nano‐architecture. These spatially resolved and hierarchically structured quinary hybrids are generated via a two‐dimensional (2D)‐functionalization‐mediated atomic layer deposition growth process, involving an initial lateral molecular programming of the graphene lattice via lithography‐assisted 2D functionalization and a subsequent stepwise molecular assembly in these regions in the z‐direction. Our breakthrough lays the foundation for the construction of emerging 3D‐patterned graphene heterostructures. [ABSTRACT FROM AUTHOR]

The ability to monitor and quantify glutathione (GSH) in live cells is essential in order to gain a detailed understanding of GSH-related pathological events. However, owing to their irreversible response mechanisms, most existing fluorescent GSH probes are not suitable for this purpose. We have developed a ratiometric fluorescent probe (QG- 1) for quantitatively monitoring cellular GSH. The probe responds specifically and reversibility to GSH with an ideal dissociation constant ( Kd) of 2.59 m m and a fast response time ( t1/2=5.82 s). We also demonstrate that QG- 1 detection of GSH is feasible in a model protein system. QG- 1 was found to have extremely low cytotoxicity and was applied to determine the GSH concentration in live HeLa cells (5.40±0.87 m m). [ABSTRACT FROM AUTHOR]

The ability to analyze highly toxic chemical warfare agents (CWAs) and related chemicals in a rapid and precise manner is essential in order to alleviate serious threats to humankind and public security caused by unexpected terrorist attacks and industrial accidents. In this investigation, we designed a o-phenylenediamine-pyronin linked dye that is capable of both fluorogenic and colorimetric discrimination between phosgene and the prototypical nerve-agent mimic, diethyl chlorophosphate (DCP) in the solution or gas phase. Moreover, this dye has been used to construct a portable kit that can be employed for real-time monitoring of DCP and phosgene in the field, both in a discriminatory manner, and in a simple and safe way. [ABSTRACT FROM AUTHOR]

The integration of 2D covalent organic frameworks (COFs) with atomic thickness with graphene will lead to intriguing two-dimensional materials. A surface-confined covalently bonded Schiff base network was prepared on single-layer graphene grown on copper foil and the dynamic reaction process was investigated with scanning tunneling microscopy. DFT simulations provide an understanding of the electronic structures and the interactions between the surface COF and graphene. Strong coupling between the surface COF and graphene was confirmed by the dispersive bands of the surface COF after interaction with graphene, and also by the experimental observation of tunneling condition dependent contrast of the surface COF. [ABSTRACT FROM AUTHOR]

The immune checkpoint blockade strategy has improved the survival rate of late‐stage lung cancer patients. However, the low immune response rate limits the immunotherapy efficiency. Here, we report a ROS‐responsive Fe3O4‐based nanoparticle that undergoes charge reversal and disassembly in the tumor microenvironment, enhancing the uptake of Fe3O4 by tumor cells and triggering a more severe ferroptosis. In the tumor microenvironment, the nanoparticle rapidly disassembles and releases the loaded GOx and the immune‐activating peptide Tuftsin under overexpressed H2O2. GOx can consume the glucose of tumor cells and generate more H2O2, promoting the disassembly of the nanoparticle and drug release, thereby enhancing the therapeutic effect of ferroptosis. Combined with Tuftsin, it can more effectively reverse the immune‐suppressive microenvironment and promote the recruitment of effector T cells in tumor tissues. Ultimately, in combination with α‐PD‐L1, there is significant inhibition of the growth of lung metastases. Additionally, the hyperpolarized 129Xe method has been used to evaluate the Fe3O4 nanoparticle‐mediated immunotherapy, where the ventilation defects in lung metastases have been significantly improved with complete lung structure and function recovered. The ferroptosis‐enhanced immunotherapy combined with non‐radiation evaluation methodology paves a new way for designing novel theranostic agents for cancer therapy. [ABSTRACT FROM AUTHOR]

Achieving circularly polarized organic ultralong room‐temperature phosphorescence (CP‐OURTP) with a high luminescent dissymmetry factor (glum) is crucial for diverse optoelectronic applications. In particular, dynamically controlling the dissymmetry factor of CP‐OURTP can profoundly advance these applications, but it is still unprecedented. This study introduces an effective strategy to achieve photoirradiation‐driven chirality regulation in a bilayered structure film, which consists of a layer of soft helical superstructure incorporated with a light‐driven molecular motor and a layer of room‐temperature phosphorescent (RTP) polymer. The prepared bilayered film exhibits CP‐OURTP with an emission lifetime of 805 ms and a glum value up to 1.38. Remarkably, the glum value of the resulting CP‐OURTP film can be reversibly controlled between 0.6 and 1.38 over 20 cycles by light irradiation, representing the first example of dynamically controlling the glum in CP‐OURTP. [ABSTRACT FROM AUTHOR]

To realize sensing and labeling biomarkers is quite challenging in terms of designing multimodal imaging probes. In this study, we developed a novel β‐galactosidase (β‐gal) activated bimodal imaging probe that combines near‐infrared (NIR) fluorescence and magnetic resonance imaging (MRI) to enable real‐time visualization of activity in living organisms. Upon β‐gal activation, Gal‐Cy‐Gd‐1 exhibits a remarkable 42‐fold increase in NIR fluorescence intensity at 717 nm, allowing covalent labeling of adjacent target enzymes or proteins and avoiding molecular escape to promote probe accumulation at the tumor site. This fluorescence reaction enhances the longitudinal relaxivity by approximately 1.9 times, facilitating high‐resolution MRI. The unique features of Gal‐Cy‐Gd‐1 enable real‐time and precise visualization of β‐gal activity in live tumor cells and mice. The probe's utilization aids in identifying in situ ovarian tumors, offering valuable assistance in the precise removal of tumor tissue during surgical procedures in mice. The fusion of NIR fluorescence and MRI activation through self‐immobilizing target enzymes or proteins provides a robust approach for visualizing β‐gal activity. Moreover, this approach sets the groundwork for developing other activatable bimodal probes, allowing real‐time in vivo imaging of enzyme activity and localization. [ABSTRACT FROM AUTHOR]

Cell surface engineering with functional polymers is an effective strategy to modulate cell activity. Here, a bio‐palladium catalyzed polymerization strategy was developed for in situ synthesis of conjugated polymers on living cell surfaces. Through Sonagashira polymerization, photoactive polyphenyleneethynylene (PPE) is synthesized on the cell surface via cell‐generated bio‐Pd catalyst. The in situ formed PPE is identified by excellent light‐harvest capacity and blue fluorescence on the surfaces of E. coli and C. pyrenoidosa. Besides imaging microbes for tracing the polymerization process, PPE also exhibits enhanced antibacterial activity against E. coli. It can also augment the ATP synthesis of C. pyrenoidosa through enlarging the light absorption and accelerating the cyclic electron transport of the algae. With this bio‐metal catalyzed polymerization method, functional polymers can be synthesized in situ on the living cell surface. [ABSTRACT FROM AUTHOR]

Activation of nitromethane to endow new reactivity is an interesting and meaningful but also challenging topic. Herein, we report an electrochemical activation of nitromethane to serve as both the heterocyclic skeleton and oxime sources for the construction of isoxazoline aldoximes. The isoxazoline aldoximes that are prepared by four steps with the reported strategy are synthesized in a single step from low‐cost and readily available nitromethane and olefins with moderate to excellent yields under our electrochemical conditions. The reaction also takes advantage of high atom‐economy and E‐selectivity. Moreover, the mechanism is studied by control experiments, a kinetic isotope effect (KIE) study, cyclic voltammogram (CV) experiments, and density functional theory (DFT) calculations. The mechanistic results reveal that nitromethane may be activated under electrochemical conditions to deliver a 1,2,5‐oxadiazole 2‐oxide intermediate, which undergoes [3+2] cycloaddition with olefins to yield isoxazoline aldoximes. [ABSTRACT FROM AUTHOR]

In‐cell NMR spectroscopy is an effective tool for observing proteins at atomic resolution in their native cellular environment. However, its utility is limited by its low sensitivity and the extensive line broadening caused by nonspecific interactions in the cells, which is even more pronounced in human cells due to the difficulty of overexpressing or delivering high concentrations of isotopically labeled proteins. Here, we present a high‐sensitivity tag (wPSP‐6F) containing two trifluoromethyl groups that can efficiently label globular proteins with molecular weights in the 6–40 kDa range under mild conditions. This tag allowed us to detect globular proteins in human cells at concentrations as low as 1.0 μM, which would not have been achievable with 15N or 3‐fluorotyrosine labeling. Moreover, we detected conformational changes and interactions of proteins in the cellular environment. The new sensitive 19F NMR tag may significantly expand the scope of protein NMR in human cells. [ABSTRACT FROM AUTHOR]

Colibactin is a small molecule produced by certain bacterial species of the human microbiota that harbour the pks genomic island. Pks+ bacteria induce a genotoxic phenotype in eukaryotic cells and have been linked with colorectal cancer progression. Colibactin is produced in a benign, prodrug form which, prior to export, is enzymatically matured by the producing bacteria to its active form. Although the complete structure of colibactin has not been determined, key structural features have been described including an electrophilic cyclopropane motif, which is believed to alkylate DNA. To investigate the influence of the putative "warhead" and the prodrug strategy on genotoxicity, a series of photolabile colibactin probes were prepared that upon irradiation induced a pks+ like phenotype in HeLa cells. Furthermore, results from DNA cross‐linking and imaging studies of clickable analogues enforce the hypothesis that colibactin effects its genotoxicity by directly targeting DNA. Photoactivated‐colibactin probes provoke a cellular phenotype that is consistent with the DNA damage observed during infection with colibactin‐producing bacteria. DNA cross‐linking and cellular localization studies support the hypothesis that the colibactin warhead targets nuclear DNA. [ABSTRACT FROM AUTHOR]

Nitroreductase (NTR) is an important biomarker widely used to evaluate the degree of tumor hypoxia. Although a few optical methods have been reported for detecting nitroreductase at low concentration ranges, an effective strategy for nitroreductase monitoring in vivo without limits to the imaging depth is still lacking. Herein, a novel dual‐mode NIR fluorescence and 19F MRI agent, FCy7‐NO2, is proposed for imaging tumor hypoxia. We show that FCy7‐NO2 serves as not only a rapid NIR fluorescence enhanced probe for monitoring and bioimaging of nitroreductase in tumors, but also a novel 19F MR chemical shift‐sensitive contrast agent for selectively detecting nitroreductase catalyzed reduction. Notably, integrating two complementary imaging technologies into FCy7‐NO2 enables sensitive detection of nitroreductase in a broad concentration range without tissue‐depth limit. In general, this agent has a remarkable response to nitroreductase, which provides a promising method for understanding tumor evolution and its physiological role in the hypoxic microenvironment. [ABSTRACT FROM AUTHOR]

Achieving efficient catalytic conversion over a heterogeneous catalyst with excellent resistance against leaching is still a grand challenge for sustainable chemical synthesis in aqueous solution. Herein, we devised a single‐atom Pt1/hydroxyapatite (HAP) catalyst via a simple hydrothermal strategy. Gratifyingly, this robust Pt1/HAP catalyst exhibits remarkable catalytic selectivity and catalyst stability for the selective oxidation of C2–C4 polyols to corresponding primary hydroxy acids. It is found that the Pt−(O−P) linkages with strong electron‐withdrawing function of PO43− (Pt1−OPO43− pair active site) not only realize the activation of the C−H bond, but also destabilize the transition state from adsorbed hydroxy acids toward the C−C cleavage, resulting in the sharply increased selectivity of hydroxy acids. Moreover, the strong PO43−‐coordination effect provides electrostatic stabilization for single‐atom Pt, ensuring the highly efficient catalysis of Pt1/HAP for over 160 hours with superior leaching resistance. [ABSTRACT FROM AUTHOR]

The enantioselective conjugated addition of tritylthiol to in situ generated ortho-quinone methides ( o-QMs) is catalyzed by an acid-base bifunctional squaramide organocatalyst. The transformation proceeds with high yield (up to 99 %) and stereoselectivity (up to 97:3 e.r.) using water as solvent under mild conditions. The catalyst system provides a new strategy for the synthesis of optically active benzyl mercaptans. Control experiments suggested that o-QMs are generated by the tertiary amine moiety of the squaramide organocatalyst and that the water-oil biphase is crucial for achieving high reactivity and stereoselectivity. [ABSTRACT FROM AUTHOR]

It has been long‐pursued but remains a challenge to precisely manipulate the molecular assembly process to obtain desired functional structures. Reported here is the control over the assembly of solute molecules, by a programmed recrystallization of solvent crystal grains, to form micro/nanoparticles with tunable sizes and crystalline forms. A quantitative correlation between the protocol of recrystallization temperature and the assembly kinetics results in precise control over the size of assembled particles, ranging from single‐atom catalysts, pure drug nanoparticles, to sub‐millimeter organic‐semiconductor single crystals. The extensive regulation of the assembly rates leads to the unique and powerful capability of tuning the stacking of molecules, involving the formation of single crystals of notoriously crystallization‐resistant molecules and amorphous structures of molecules with a very high propensity to crystallize, which endows it with wide‐ranging applications. [ABSTRACT FROM AUTHOR]

Direct conversion of methane to value‐added chemicals with high selectivity under mild conditions remains a great challenge in catalysis. Now, single chromium atoms supported on titanium dioxide nanoparticles are reported as an efficient heterogeneous catalyst for direct methane oxidation to C1 oxygenated products with H2O2 as oxidant under mild conditions. The highest yield for C1 oxygenated products can be reached as 57.9 mol molCr−1 with selectivity of around 93 % at 50 °C for 20 h, which is significantly higher than those of most reported catalysts. The superior catalytic performance can be attributed to the synergistic effect between single Cr atoms and TiO2 support. Combining catalytic kinetics, electron paramagnetic resonance, and control experiment results, the methane conversion mechanism was proposed as a methyl radical pathway to form CH3OH and CH3OOH first, and then the generated CH3OH is further oxidized to HOCH2OOH and HCOOH. [ABSTRACT FROM AUTHOR]

Chiral α‐hydroxyl acids are of great importance in chemical synthesis. Current methods for recognizing their chirality by 1H NMR are limited by their small chemical shift differences and intrinsic solubility problem in organic solvents. Herein, we developed three YbDO3A(ala)3 derivatives to recognize four different commercially available chiral α‐hydroxyl acids in aqueous solution through 1H NMR and chemical exchange saturation transfer (CEST) spectroscopy. The shift difference between chiral α‐hydroxyl acid observed by proton and CEST NMR ranged from 15–40 and 20–40 ppm, respectively. Our work demonstrates for first time, that even one chiral center on the side‐arm chain of cyclen could set the stage for rotation of the other two non‐chiral side chains into a preferred position. This is ascribed to the lower energy state of the structure. The results show that chiral YbDO3A‐like complexes can be used to discriminate chiral α‐hydroxyl acids with a distinct signal difference. [ABSTRACT FROM AUTHOR]

Abstract: Fluorooxoborates, benefiting from the large optical band gap, high anisotropy, and ever‐greater possibility to form non‐centrosymmetric structures activated by the large polarization of [BOxF4−x](x+1)− building blocks, have been considered as the new fertile fields for searching the ultraviolet (UV) and deep‐UV nonlinear optical (NLO) materials. Herein, we report the first asymmetric alkaline‐earth metal fluorooxoborate SrB5O7F3, which is rationally designed by taking the classic Sr2Be2B2O7 (SBBO) as a maternal structure. Its [B5O9F3]6− fundamental building block with near‐planar configuration composed by two edge‐sharing [B3O6F2]5− rings in SrB5O7F3 has not been reported in any other borates. Solid state 19F and 11B magic‐angle spinning NMR spectroscopy verifies the presence of covalent B−F bonds in SrB5O7F3. Property characterizations reveal that SrB5O7F3 possesses the optical properties required for deep‐UV NLO applications, which make SrB5O7F3 a promising crystal that could produce deep‐UV coherent light by the direct SHG process. [ABSTRACT FROM AUTHOR]

Two new bithiophene imide (BTI)-based n-type polymers were synthesized. f-BTI2-FT based on a fused BTI dimer showed a smaller band gap, a lower LUMO, and higher crystallinity than s-BTI2-FT containing a BTI dimer connected through a single bond. s-BTI2-FT exhibited a remarkable electron mobility of 0.82 cm2 V−1 s−1, and f-BTI2-FT showed a further improved mobility of 1.13 cm2 V−1 s−1 in transistors. When blended with the polymer donor PTB7-Th, f-BTI2-FT-based all-polymer solar cells (all-PSCs) attained a PCE of 6.85 %, the highest value for an all-PSC not based on naphthalene (or perylene) diimide polymer acceptors. However, s-BTI2-FT all-PSCs showed nearly no photovoltaic effect. The results demonstrate that f-BTI2-FT is one of most promising n-type polymers and that ring fusion offers an effective approach for designing polymers with improved electrical properties. [ABSTRACT FROM AUTHOR]

A novel radical [1,3]-nitrogen shift catalyzed by copper diacetate under an oxygen atmosphere (1 atm) has been developed for the construction of a diverse range of indole derivatives from α,α-disubstituted benzylamine. In this reaction, oxygen was used as a clean terminal oxidant, and water was produced as the only by-product. Five inert bonds were cleaved, and two C−N bonds and one C−C double bond were constructed in one pot during this transformation. This unique method demonstrated broad application protential for the late-stage modification of biologically active natural products and drugs. Mechanistic investigations indicate that a unique 4- exo-trig cyclization of an aminyl radical onto a phenyl ring is involved in the catalytic cycle. [ABSTRACT FROM AUTHOR]

The giant protein titin plays a critical role in regulating the passive elasticity of muscles, mainly through the stochastic unfolding and refolding of its numerous immunoglobulin domains in the I-band of sarcomeres. The unfolding dynamics of titin immunoglobulin domains at a force range greater than 100 pN has been studied by atomic force microscopy, while that at smaller physiological forces has not been measured before. By using magnetic tweezers, it is found that the titin I27 domain unfolds in a surprising non-monotonic force-dependent manner at forces smaller than 100 pN, with the slowest unfolding rate occurring around 22 pN. We further demonstrate that a model with single unfolding pathway taking into account the elasticity of the transition state can reproduce the experimental results. These results provide important novel insights into the regulation mechanism of the passive elasticity of muscle tissues. [ABSTRACT FROM AUTHOR]

A bimodal imaging probe FCy7‐NO2 was applied to image nitroreductase overexpressed by lung cancer in vivo, as reported by Xin Zhou and co‐workers in their Research Article (e202213495). Integrating two complementary imaging technologies into FCy7‐NO2 enables sensitive detection of nitroreductase over a broad concentration range without tissue‐depth limit. [ABSTRACT FROM AUTHOR]

Inside Back Cover: In Vivo Nitroreductase Imaging via Fluorescence and Chemical Shift Dependent 19F NMR (Angew. Integrating two complementary imaging technologies into FCy7-NO SB 2 sb enables sensitive detection of nitroreductase over a broad concentration range without tissue-depth limit. 19F MRI, Biosensors, Fluorescence Imaging, Hypoxia, Nitroreductase. [Extracted from the article]

Achieving efficient catalytic conversion over a heterogeneous catalyst with excellent resistance against leaching is still a grand challenge for sustainable chemical synthesis in aqueous solution. Herein, we devised a single‐atom Pt1/hydroxyapatite (HAP) catalyst via a simple hydrothermal strategy. Gratifyingly, this robust Pt1/HAP catalyst exhibits remarkable catalytic selectivity and catalyst stability for the selective oxidation of C2–C4 polyols to corresponding primary hydroxy acids. It is found that the Pt−(O−P) linkages with strong electron‐withdrawing function of PO43− (Pt1−OPO43− pair active site) not only realize the activation of the C−H bond, but also destabilize the transition state from adsorbed hydroxy acids toward the C−C cleavage, resulting in the sharply increased selectivity of hydroxy acids. Moreover, the strong PO43−‐coordination effect provides electrostatic stabilization for single‐atom Pt, ensuring the highly efficient catalysis of Pt1/HAP for over 160 hours with superior leaching resistance. [ABSTRACT FROM AUTHOR]