Biofuel-Driven Stepping Chiral Supramolecular Transfer Container.

Herein, we reported a biofuel-driven recyclable chiral supramolecular transfer container based on hexacationic triphenylamine cage and nucleotides. Possessing rotatable paddle rigid backbones, the artificial receptor effectively encapsulated nucleotides with a high binding constant up to 5.37×10 M in water, displaying guest-induced efficient fluorescence enhancement with quantum yield increased from 6.

Configurationally Stepping Confinement Achieved Tunable Chiral Near-Infrared Luminescence Supramolecular Phenothiazine Organic Framework.

Herein, thermally responsive reversible chiral supramolecules are reported, constructed by the chirality transfer from tripeptides to achiral network supramolecular organic frameworks (SOF) based on configurationally stepping confinement, which displayed not only highly selective reversible chirality transfer but also efficient enhanced near-infrared (NIR) luminescence. Taking advantage of macrocyclic confinement, CB[8] separately encapsulated two kinds of tetracationic bis(phenothiazines) derivatives (G1, G2) at 2:1 stoichiometric to form organic 2D SOFs, efficiently enhancing 12.6 fold NIR luminescence and blueshifted from 705 to 680 nm for G1, and redshifted from 695 to 710 nm for G2, respectively.

Supramolecular assembly activated single-molecule phosphorescence resonance energy transfer for near-infrared targeted cell imaging.

Pure organic phosphorescence resonance energy transfer is a research hotspot. Herein, a single-molecule phosphorescence resonance energy transfer system with a large Stokes shift of 367 nm and near-infrared emission is constructed by guest molecule alkyl-bridged methoxy-tetraphenylethylene-phenylpyridines derivative, cucurbit[n]uril (n = 7, 8) and β-cyclodextrin modified hyaluronic acid. The high binding affinity of cucurbituril to guest molecules in various stoichiometric ratios not only regulates the topological morphology of supramolecular assembly but also induces different phosphorescence emissions.

Laponite-activated AIE supramolecular assembly with modulating multicolor luminescence for logic digital encryption and perfluorinated pollutant detection.

Recently, the non-covalently activated supramolecular scaffold method has become a prominent research area in the field of intelligent materials. Here, the inorganic clay (LP) promoted the AIE properties of 4,4',4″,4‴-(ethene-1,1,2,2-tetrayltetrakis(benzene-4,1-diyl))tetrakis(1-ethylpyridin-1-ium) (P-TPE), showing an astonishing 42-fold enhancement of the emission intensity of the yellow-green luminescence and a 34-fold increase of the quantum yield via organic-inorganic supramolecular strategy as well as the efficient light-harvesting properties (energy transfer efficiency up to 33 %) after doping with the dye receptor Rhodamine B. Furthermore, the full-color spectral regulation, including white light, was achieved by adjusting the ratio of the donor to the acceptor component and co-assembling with the carbon dots (CD).

Density Functional Theory Study of the Mechanism of Ni-Catalyzed Carboxylation of Aryl C(sp)-S Bonds with CO: Computational Evidence for the Multifaceted Role of Additive Zn.

The mechanism of Ni-catalyzed carboxylation of aryl C(sp)-S bonds with CO was studied for the first time by density functional theory calculations. We first proposed another possible reaction pathway in which CO insertion occurs prior to reduction. Then, we performed calculations on all proposed reaction pathways, and our calculation results show that the pathway in which reduction occurs prior to CO insertion is the favored pathway for this reaction.

Density Functional Theory Study on the Mechanism of Nickel-Catalyzed 3,3-Dialkynylation of 2-Aryl Acrylamides Via Double Vinylic C-H Bond Activation.

The mechanisms of Ni-catalyzed 3,3-dialkynylation of 2-aryl acrylamide have been investigated by using density functional theory calculations. The result shows that this reaction includes double alkynylation, which involves sequential key steps of vinylic C-H bond activation, successive oxidative addition, and reductive elimination, with the second C-H bond activation being the rate-determining step. C-H and N-H bond activation occurs via the concerted metalation-deprotonation mechanism.

Structural deep multi-view clustering with integrated abstraction and detail.

Deep multi-view clustering, which can obtain complementary information from different views, has received considerable attention in recent years. Although some efforts have been made and achieve decent performances, most of them overlook the structural information and are susceptible to poor quality views, which may seriously restrict the capacity for clustering. To this end, we propose Structural deep Multi-View Clustering with integrated abstraction and detail (SMVC).

Quantitative Analysis of Multimodal MRI Markers and Clinical Risk Factors for Cerebral Small Vessel Disease Based on Deep Learning.

Background: Cerebral small vessel disease lacks specific clinical manifestations, and extraction of valuable features from multimodal images is expected to improve its diagnostic accuracy. In this study, we used deep learning techniques to segment cerebral small vessel disease imaging markers in multimodal magnetic resonance images and analyze them with clinical risk factors.

Methods And Results: We recruited 211 lacunar stroke patients and 83 control patients.

Bile acids inhibit ferroptosis sensitivity through activating farnesoid X receptor in gastric cancer cells.

Background: Gastric cancer (GC) is associated with high mortality rates. Bile acids (BAs) reflux is a well-known risk factor for GC, but the specific mechanism remains unclear. During GC development in both humans and animals, BAs serve as signaling molecules that induce metabolic reprogramming.

Light and Heat-Driven Flexible Solid Supramolecular Polymer Displaying Phosphorescence and Reversible Photochromism.

Herein, a type of light- and heat-driven flexible supramolecular polymer with reversibly long-lived phosphorescence and photochromism is constructed from acrylamide copolymers with 4-phenylpyridinium derivatives containing a cyano group (P-CN, P-oM, P-mM), sulfobutylether-β-cyclodextrin (SBCD), and polyvinyl alcohol (PVA). Compared to their parent solid polymers, these flexible supramolecules based on the non-covalent cross-linking of copolymers, SBCD, and PVA efficiently boost the phosphorescence lifetimes (723.0 ms for P-CN, 623.

Selective Access to Silacyclopentanes and Homoallylsilanes by La-Catalyzed Hydrosilylations of 1-Aryl Methylenecyclopropanes.

Methylenecyclopropanes (MCPs) have emerged as versatile building blocks in synthetic chemistry because of their unique reactivity. However, metal-catalyzed hydrosilylation of MCPs has met with very limited successes. In this paper, catalytic selective hydrosilylations of MCPs with some primary silanes using an ene-diamido lanthanum ate complex as the catalyst were described.

DFT Study on Mechanism of Ni-Al Bimetallic-Catalyzed C-H Cyclization to Construct Tricyclic Imidazoles: Roles of NHC Ligand and AlMe.

The mechanism of the Ni-Al bimetallic-catalyzed C-H cyclization to construct tricyclic imidazoles is investigated using density functional theory calculations. The calculation result shows that the reaction mechanism involves sequential steps of substrate coordination, ligand-to-ligand hydrogen transfer (LLHT), and C-C reductive elimination to produce the final product tricyclic imidazole. The LLHT step is calculated to be the rate-determining step.

DFT Study on the Mechanism of the Palladium-Catalyzed [3 + 2] Annulation of Aromatic Amides with Maleimides via Benzylic and -C-H Bond Activation: Role of the External Ligand Ac-Gly-OH.

The mechanism of the Ac-Gly-OH-assisted palladium-catalyzed [3 + 2] annulation of aromatic amides with maleimides is investigated using density functional theory calculations. The results show that the reaction undergoes the sequential steps of N-H bond deprotonation, first benzylic C-H bond activation, maleimide insertion, second -C-H bond activation, reductive elimination, and oxidation. The external ligand Ac-Gly-OH acts as the internal base for hydrogen abstraction in the first benzylic C-H bond activation.

Theory and experiment: The synthesis and drug application of "ON-OFF-ON" fluorescent probes for copper and biothiols detection.

Abnormal copper ions (Cu) and biothiols have potential impacts on environmental pollution and human health, so the detection of these substances with high selectivity and sensitivity has become an important research topic. In this study, we designed and synthesized two fluorescent probes (L and L) based on naphthalene and anthracene derivatives that could specifically detect Cu and biothiols. Owing to the paramagnetic effect of Cu, the strong fluorescent intensity was quenched after the addition of Cu.

Structure-aware deep clustering network based on contrastive learning.

Recently, deep clustering has been extensively employed for various data mining tasks, and it can be divided into auto-encoder (AE)-based and graph neural networks (GNN)-based methods. However, existing AE-based methods fall short in effectively extracting structural information, while GNN suffer from smoothing and heterophily. Although methods that combine AE and GNN achieve impressive performance, there remains an inadequate balance between preserving the raw structure and exploring the underlying structure.

Unimolecular Chiral Stepping Inversion Machine.

Intelligent molecular machines that are driven by light, electricity, and temperature have attracted considerable interest in the fields of chemistry, materials, and biology. Herein, a unimolecular chiral stepping inversion molecular machine (SIMM) was constructed by a coupling reaction between dibromo pillar[5]arene and a tetrathiafulvalene (TTF) derivative (PT3 and PT5). Compared with the longer aliphatic linker PT5, PT3 with a shorter aliphatic linker shows chiral stepping inversion, achieving chiral inversion under a two-electron redox potential.

Hydrogen-bonded Complex-based Frameworks for Stable Lithium Storage.

Metal-complex-based materials for lithium storage have attracted great interest due to their highly designable structures with multiple active sites and well-defined lithium transport pathways. Their cycling and rate performances, however, are still constrained by structural stability and electrical conductivity. Herein, we present two hydrogen-bonded complex-based frameworks with excellent lithium storage capability.

Computational Study of Iron-Catalyzed Intramolecular [2 + 2] Cycloaddition and Cycloisomerization of Enyne Acetates: Mechanism and Selectivity.

The mechanism of iron-catalyzed intramolecular [2 + 2] cycloaddition and cycloisomerization of enyne acetates has been investigated with DFT computations. Both mechanisms start the catalytic cycle from the stepwise 1,2-acyloxy migration to afford the iron carbene. The [2 + 2] cycloaddition mechanism involves subsequent key steps of [2 + 2] cycloaddition, 1,2-acyloxy migration, and reductive elimination to generate the azabicyclo [3.

Efficient Recognition and Removal of Persistent Organic Pollutants by a Bifunctional Molecular Material.

Persistent organic pollutants (POPs) exist widely in the environment and place significant impact on human health by bioaccumulation. Efficient recognition of POPs and their removal are highly challenging tasks because their specific structures interact often very weakly with the capture materials. Herein, a molecular nanocage () is studied as an efficient sensing and sorbent material for POPs, which is demonstrated by a representative and stable perfluorooctane sulfonate (PFOS) substrate containing a hydrophilic sulfonic group and a hydrophobic fluoroalkyl chain.

C3-Cyanation of Pyridines: Constraints on Electrophiles and Determinants of Regioselectivity.

Methods for C-H cyanation of pyridines are rare. Here, we report a method for C3-selective cyanation of pyridines by a tandem process with the reaction of an in situ generated dihydropyridine with a cyano electrophile as the key step. The method is suitable for late-stage functionalization of pyridine drugs.

A tunable full-color lanthanide noncovalent polymer based on cucurbituril-mediated supramolecular dimerization.

The construction of lanthanide multicolor luminescent materials with tunable photoluminescence properties has been developed as one of the increasingly significant topics and shown inventive applications in miscellaneous fields. However, fabricating such materials based on synergistically assembly-induced emission rather than simple blending of different fluorescent dyes together still remains a challenge. Herein, we report a europium-based noncovalent polymer with tunable full-color emission, which is constructed from the 2,6-pyridinedicarboxylic acid-bearing bromophenylpyridinium salt.

Application of Diffusion Tensor Imaging Based on Automatic Fiber Quantification in Alzheimer's Disease.

Background: Neuroimaging suggests that white matter microstructure is severely affected in Alzheimer's disease (AD) progression. However, whether alterations in white matter microstructure are confined to specific regions and whether they can be used as potential biomarkers to distinguish normal control (NC) from AD are unknown.

Methods: In this cross-sectional study, 33 cases of AD and 25 cases of NC were recruited for automatic fiber quantification (AFQ).

Conformationally Confined Emissive Cationic Macrocycle with Photocontrolled Organelle-Specific Translocation.

The optimization of molecular conformation and aggregation modes is of great significance in creation of new luminescent materials for biochemical research and medical diagnostics. Herein, a highly emissive macrocycle (1) is reported, which is constructed by the cyclization reaction of triphenylamine with benzyl bromide and exhibits very distinctive photophysical performance both in aqueous solution and the solid state. Structural analysis reveals that the 1 can form self-interpenetrated complex and emit bright yellow fluorescence in the crystal lattice.

Cyclodextrin-Confined Supramolecular Lanthanide Photoswitch.

The utilization of azobenzene-based photoisomerization cannot only control the morphology of supramolecular assemblies, but can also regulate many biological processes. However, the design of azobenzene-involved nanoconstructs with switchable photoluminescence remains challenging because of the light-quenching ability of azobenzene. Herein, an azobenzene-derived multicomponent nanosystem is reported and its function as a supramolecular lanthanide photoswitch is explored.

Generation of Allogeneic CAR T Cells through Specific Degradation of the T Cell Antigen Receptor by E3 Ubiquitin Ligase Fusion Proteins.

Receptor downregulation is instrumental for many therapeutic interventions. Receptor knockout through gene-editing technologies is efficient but can introduce off-target mutations and chromothripsis. Regulation of gene expression at the protein level is a promising alternative.