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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. Uncommonly, the tripeptide coassembled with two kinds of achiral noncovalent frameworks (G1/CB[8] or G2/CB[8]) displayed different opposite circular dichroism signals based on different binding modes and affinity, achieving chirality transfer from tripeptide to organic supramolecular assemblies with further enhanced NIR fluorescence up to 46.2 times and the quantum yield (QY) increased from 0.71% to 10.29% for G2/CB[8], showing reversible chirality transfer and tunable NIR fluorescence under thermal stimulus. Therefore, the current research has achieved controllable chirality transfer from tripeptide to the SOFs and the enhancement of tunable NIR fluorescence, which is successfully applied in thermal responsive chiral logic gates, information encryption, and cell imaging. [ABSTRACT FROM AUTHOR]

Clustering ensembles can obtain more superior final results by combining multiple different clustering results. The qualities of the points, clusters, and partitions play crucial roles in the consistency of the clustering process. However, existing methods mostly focus on one or two aspects of them, without a comprehensive consideration of the three aspects. This paper proposes a three-level weighted clustering ensemble algorithm namely unified point-cluser-partition algorithm (PCPA). The first step of the PCPA is to generate the adjacency matrix by base clusterings. Then, the central step is to obtain the weighted adjacency matrix by successively weighting three layers, i.e., points, clusters, and partitions. Finally, the consensus clustering is obtained by the average link method. Three performance indexes, namely F, NMI, and ARI, are used to evaluate the accuracy of the proposed method. The experimental results show that: Firstly, as expected, the proposed three-layer weighted clustering ensemble can improve the accuracy of each evaluation index by an average value of 22.07% compared with the direct clustering ensemble without weighting; Secondly, compared with seven other methods, PCPA can achieve better clustering results and the proportion that PCPA ranks first is 28/33. [ABSTRACT FROM AUTHOR]

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. Varying from the spherical nanoparticles and nanorods for binary assemblies, three-dimensional nanoplate is obtained by the ternary co-assembly of guest with cucurbit[7]uril/cucurbit[8]uril, accompanying enhanced phosphorescence at 540 nm. Uncommonly, the secondary assembly of β-cyclodextrin modified hyaluronic acid and ternary assembly activates a single intramolecular phosphorescence resonance energy transfer process derived from phenyl pyridines unit to methoxy-tetraphenylethylene function group, enabling a near-infrared delayed fluorescence at 700 nm, which ultimately applied to mitochondrial targeted imaging for cancer cells.Phosphorescence resonance energy transfer systems have potential in light-harvesting and bioimaging, but host-guest systems are rarely explored. Here, the authors report the development of a macrocyclic host-guest system for targeted cell imaging. [ABSTRACT FROM AUTHOR]

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. The patients' cerebral small vessel disease markers were automatically segmented using a V-shaped bottleneck network, and the number and volume were calculated after manual correction. The segmentation results of the V-shaped bottleneck network for white matter hyperintensity and recent small subcortical infarction were in high agreement with the ground truth (DSC> 0.90). In small lesion segmentation, cerebral microbleed (average recall=0.778; average precision=0.758) and perivascular spaces (average recall=0.953; average precision=0.923) were superior to lacunar infarct (average recall=0.339; average precision=0.432) in recall and precision. Binary logistic regression analysis showed that age, systolic blood pressure, and total cerebral small vessel disease load score were independent risk factors for lacunar stroke (P< 0.05). Ordered logistic regression analysis showed age was positively correlated with cerebral small vessel disease load score and total cholesterol was negatively correlated with cerebral small vessel disease score (P< 0.05). Conclusion: Lacunar stroke patients exhibited higher cerebral small vessel disease imaging markers, and age, systolic blood pressure, and total cerebral small vessel disease score were independent risk factors for lacunar stroke patients. V-shaped bottleneck network segmentation network based on multimodal deep learning can segment and quantify various cerebral small vessel disease lesions to some extent. [ABSTRACT FROM AUTHOR]

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. Multiple hydrogen bonds among the mononuclear molecules result in three‐dimensional frameworks that are stable in electrolyte. The origin of the remarkable lithium storage performance of this family was revealed through kinetic analysis and DFT calculations. [ABSTRACT FROM AUTHOR]

Herein, two kinds of amorphous solid‐state supramolecular systems with purely organic room temperature phosphorescence (RTP) from calix[3]phenothiazine (C[3]Pz) activated by 1,2‐/1,3‐dicyanobenzene (1,2‐/1,3‐DCB) are reported. Different from macrocycle‐confined guest phosphorescence emission, RTP of these two amorphous solid‐state supramolecular systems is entirely from the 1,2‐/1,3‐DCB rivets C[3]Pz cavity to form dense supramolecular complex through CH...π interactions, leading to two different phosphorescence emissions at 566/524 nm under 430 nm excitation, respectively. Although C[3]Pz shows a regular arrangement in the crystal, the vibration dissipation of the benzene ring results in C[3]Pz emitting only fluorescence at 508 nm at room temperature. 1,2‐DCB and 1,3‐DCB can act as molecular rivets to fix the C[3]Pz to inhibit molecular vibration so as to reduce nonradiative relaxation, which enables C[3]Pz to achieve effective RTP emission with 20.8–36.8% quantum yields. This kind of guest‐activated host RTP, which is fairly rare in supramolecular systems, is successfully used for color QR codes and information encryption. [ABSTRACT FROM AUTHOR]

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. The low reduction potential of the electrophile and effective transfer of the nitrile group were found to be essential for the success of this method. We studied the reaction mechanism in detail by means of control experiments and theoretical calculations and found that a combination of electronic and steric factors determined the regioselectivity of reactions involving C2‐substituted pyridines. [ABSTRACT FROM AUTHOR]

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. The low reduction potential of the electrophile and effective transfer of the nitrile group were found to be essential for the success of this method. We studied the reaction mechanism in detail by means of control experiments and theoretical calculations and found that a combination of electronic and steric factors determined the regioselectivity of reactions involving C2‐substituted pyridines. [ABSTRACT FROM AUTHOR]

We have developed a synthetic strategy for Et3N‐promoted [5+3] cycloaddition reactions between acetoxypyranones and azomethine imines to access functionalized azabicyclo[3.3.1]alkenones with three tertiary stereocenters (31 examples, 36% to 87% yield, 5.5:1 to >20:1 dr). The method was scalable, and the products could be transformed to various eight‐membered‐ring bridged heterocyclic molecules. [ABSTRACT FROM AUTHOR]

A purely organic supramolecular assembly emitting three‐photon room‐temperature phosphorescence (RTP) is constructed from a macrocyclic host, cucurbit[8]uril (CB[8]), and 4‐bromophenyl pyridine salt having an alkyl chain length of 6 or 12 carbon atoms (6C and 12C, respectively). Benefiting from macrocyclic host confined guests, the encapsulation of 12C and 6C in the CB[8] cavity results in three‐photon absorption and subsequent near‐infrared (NIR) phosphorescence emission. Notably, secondary assembly with sulfonated β‐cyclodextrin (SCD) further enhances the phosphorescence emission of the multilevel supramolecular assembly. NIR‐delayed fluorescence via a light‐harvesting phosphorescent energy transfer system is achieved by adding Nile blue as a substrate. Comparison of 12C/CB[8]/SCD and 6C/CB[8]/SCD shows that a long hydrophobic layer is more conducive to stabilizing NIR‐delayed fluorescence emission. These findings indicate that multilevel supramolecular assemblies can be used for three‐photon‐excited NIR‐delayed fluorescence and RTP imaging of cancer cells, which greatly expands the biological applications of pure organic RTP materials. [ABSTRACT FROM AUTHOR]

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. The distorted yet symmetrical structure can endow 1 with unique two‐photon absorption property upon excitation by near‐infrared light. Also, 1 can be utilized as an efficient photosensitizer to produce singlet oxygen (1O2) both in inanimate milieu and under cellular environment. More intriguingly, due to the strong association of 1 with negatively charged biomacromolecules, organelle‐specific migration is achieved from lysosome to nucleus during the 1O2‐induced cell apoptosis process. To be envisaged, this conformationally confined cationic macrocycle with photocontrolled lysosome‐to‐nucleus translocation may provide a feasible approach for in situ identifying different biospecies and monitoring physiological events at subcellular level. [ABSTRACT FROM AUTHOR]

Two colorimetric and fluorescent probes based on ferrocene derivatives have been designed and synthesized. Among studied anions (F−, AcO−, H2PO4−, Cl−, Br− and I−), probe 1 with p‐nitrophenyl hydrazine structure has the strongest binding ability for F−, as well as probe 2 for H2PO4−. It had strong binding ability and was not affected by other anions. The determination limit of 1 toward F− was 5.0×10−6 mol⋅L−1 which can be used for the trace detection of F−. The interacted process of host–guest accompanied by colorimetric changes and increment in fluorescent intensity of the probes. A 1H‐NMR titration experiment and theoretical investigation indicated that −NH in hydrazine participated in the interaction, and the hydrogen‐bonding formed between the probes and anions. These results provided an essential clue to the developing the colorimetric probe based on hydrazine participation. [ABSTRACT FROM AUTHOR]

Regulation of physio‐chemical properties and reaction activities via noncovalent methodology has become one of increasingly significant topics in supramolecular chemistry and showed inventive applications in miscellaneous fields. Herein, we demonstrate that sulfonated crown ether can form very stable host‐guest complexes with a series of push‐pull‐type photosensitizers, eventually leading to the dramatic fluorescence enhancement in visible and near‐infrared regions. Meanwhile, severe suppression in singlet oxygen (1O2) production is found, mainly due to the higher energy barriers between the excited single and triple states upon host‐guest complexation. Moreover, such complexation‐induced tuneable 1O2 generation systems has been utilized in adjusting the photochemical oxidation reactions of polycyclic aromatic hydrocarbons (anthracene) and sulfides ((methylthio)benzene) in water. This supramolecularly controlled photooxidation based on the selective molecular binding of crown ether with photosensitizers may provide a feasible and applicable strategy for monitoring and modulating many photocatalysis processes in aqueous phase. [ABSTRACT FROM AUTHOR]

The photoreversible switch persistent room‐temperature phosphorescent (p‐RTP) system is attractive but challenging in the field of smart luminescent materials. In particular, those p‐RTPs with the excitation‐wavelength‐responsive and time‐dependent multicolor emission are very important but underexplored. Herein an excitation‐wavelength‐responsive and time‐dependent multicolor p‐RTP emission pseudopolyrotaxanes supramolecular system based on host–guest interaction between α‐cyclodextrin (α‐CD) and two luminophores (benzene and naphthalene) modified polyethylene glycol (PEG) derivatives is reported. The excitation‐wavelength‐responsive and time‐dependent multicolor afterglows of the supramolecular system are derived from the diverse p‐RTP emission species with different lifetimes. More importantly, the p‐RTP can be reversibly adjusted by photoisomerization of diarylethylene (DAE), that is, it could be erased under ultraviolet light and recovered under visible‐light for several cycles. Taking advantage of the reversible photoencryption property, this intelligent luminescence supramolecular system has broad application prospects in information storage and treatment. [ABSTRACT FROM AUTHOR]

A series of solid supramolecules based on acrylamide–phenylpyridium copolymers with various substituent groups (P−R: R=−CN, −CO2Et, −Me, −CF3) and cucurbit[7]uril (CB[7]) are constructed to exhibit tunable second‐level (from 0.9 s to 2.2 s) room‐temperature phosphorescence (RTP) in the amorphous state. Compared with other solid supramolecules P−R/CB[7] (R=−CN, −CO2Et, −Me), P−CF3/CB[7] displays the longest lifetime (2.2 s), which is probably attributed to the fluorophilic interaction of cucurbiturils leading to a uncommon host–guest interaction between 4‐phenylpyridium with −CF3 and CB[7]. Furthermore, the RTP solid supramolecular assembly (donors) can further react with organic dyes Eosin Y or SR101 (acceptors) to form ternary supramolecular systems featuring ultralong phosphorescence energy transfer (PpET) and visible delayed fluorescence (yellow for EY at 568 nm and red for SR101 at 620 nm). Significantly, the ultralong multicolor PpET supramolecular assembly can be further applied in fields of anti‐counterfeiting and information encryption and painting. [ABSTRACT FROM AUTHOR]

A series of solid supramolecules based on acrylamide–phenylpyridium copolymers with various substituent groups (P−R: R=−CN, −CO2Et, −Me, −CF3) and cucurbit[7]uril (CB[7]) are constructed to exhibit tunable second‐level (from 0.9 s to 2.2 s) room‐temperature phosphorescence (RTP) in the amorphous state. Compared with other solid supramolecules P−R/CB[7] (R=−CN, −CO2Et, −Me), P−CF3/CB[7] displays the longest lifetime (2.2 s), which is probably attributed to the fluorophilic interaction of cucurbiturils leading to a uncommon host–guest interaction between 4‐phenylpyridium with −CF3 and CB[7]. Furthermore, the RTP solid supramolecular assembly (donors) can further react with organic dyes Eosin Y or SR101 (acceptors) to form ternary supramolecular systems featuring ultralong phosphorescence energy transfer (PpET) and visible delayed fluorescence (yellow for EY at 568 nm and red for SR101 at 620 nm). Significantly, the ultralong multicolor PpET supramolecular assembly can be further applied in fields of anti‐counterfeiting and information encryption and painting. [ABSTRACT FROM AUTHOR]

Although purely organic room‐temperature phosphorescence (RTP) has drawn widespread attention in recent years, regulatable phosphorescence resonance energy transfer (PRET) supramolecular switch is still rare. Herein, single molecular dual‐fold supramolecular light switches, which are constructed by phenylpyridinium salts modified diarylethene derivatives (DTE‐Cn, n = 3, 5) and cucurbit[8]uril (CB[8]) are reported. Significantly, biaxial [3]pseudorotaxane displayed efficiently reversible RTP after binding with CB[8] and the phosphorescence quenching efficiency is calculated up to be 99%. Furthermore, the binary supramolecular assembly can coassemble with Cy5 to form ternary supramolecular assembly showing efficiently PRET, which is successfully applied in switchable near infrared (NIR) mitochondria‐targeted cell imaging and photocontrolled data encryption. This supramolecular strategy involving energy transfer provides a convenient approach for phosphorescent application in biology and material fields. [ABSTRACT FROM AUTHOR]

K[CpFe(CO)2] and [NEt4][CpFe(CO)2] enabled highly efficient hydrosilylation of ketones and aldehydes with PhSiH3 to synthesize tris- and bis(alkoxy)silanes in excellent yields depending on the substituents on the carbonyl compounds. The catalyst represents one of the most efficient and practical iron catalysts for hydrosilylation of carbonyl compounds with a TOF up to 24 540 h−1. [ABSTRACT FROM AUTHOR]

Sn-based compounds with buffer matrixes possessing high theoretical capacity, low working voltage, and alleviation of the volume expansion of Sn are ideal materials for lithium storage. However, it is challenging to confine well-dispersed Sn within a lithium active matrix because low-melting-point Sn tends to agglomerate. Here, we apply a metal-organic framework (MOF) chemistry between Sn-nodes and lithium active ligands to create two Sn-based MOFs comprising Sn2(dobdc) and Sn2(dobpdc) with extended ligands from H4dobdc (2,5-dioxido-1,4-benzenedicarboxylate acid) to H4dobpdc (4,4'-dioxidobiphenyl-3,3'-dicarboxylate acid) with molecule-level homodispersion of Sn in organic matrixes for lithium storage. The enhanced utilization of active sites and reaction kinetics are achieved by the isoreticular expansion of the organic linkers. The reversible formation of coordination bonds during lithium storage processes is revealed by X-ray absorption fine structure characterization, providing an in-depth understanding of the lithium storage mechanism in coordination compounds. Tin-based alloying materials have been widely developed for lithium storage, but are limited by large volume variation. Herein, the authors created a new strategy of applying coordination chemistry to construct tin-based metal-organic frameworks which exhibited high-performance lithium storage property. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is a promising technique widely used in clinical diagnose. Poly(α-amino acid)s are excellent carriers for MRI due to their excellent biocompatibility. PDOPA-b-PSar copolymers (defined as "DoS") are synthesized by sequential polymerizations of 3,4-dihydroxy-L-phenylalanine N-thiocarboxyanhydride (DOPA-NTA) and sarcosine N-thiocarboxyanhydride (Sar-NTA) initiated by neopentylamine in tetramethylene sulfone. Mn2+@DoS micelles have been prepared as T1-weighted MRI contrast agents according to efficient coordination between catechol units and Mn2+ cation. High longitudinal relaxivity (27.7 mM−1·s−1) of Mn2+@PDOPA12-b-PSar72 was observed, and the aqueous micelle exhibits effective MRI contrast enhancement in vivo of nude mice. Mn2+@DoS shows potential clinical application in diagnostic radiology as a novel MRI contrast agent. Gd3+@DoS micelles are also investigated presenting a longitudinal relaxivity of 16.4 mM−1·s−1. Unfortunately, the Gd3+ loading percentage is quite low as 19%. [ABSTRACT FROM AUTHOR]

Coordination compounds are well‐known compounds that are being used as new materials for lithium storage because of their unique advantages, that is, designable structures, abundant active sites, and facile as well as mild synthetic routes. However, the electrode stability, low rate performance, and cycle life of coordination compounds are currently the main issues preventing their application as electrode materials, and the lithium‐storage mechanism in coordination networks is not well understood. Herein, isostructural one‐dimensional coordination compounds were synthesized to study their lithium‐storage performance. Co‐HIPA and Ni‐HIPA showed superior electrolyte stability than other M‐HIPAs, and Co‐HIPA displayed a superior reversible capacity and cycle stability, excellent rate performance, and clear voltage platform. DFT calculations and kinetic analysis revealed the influence of the metal center with different electronic structures on the lithium‐storage mechanism. [ABSTRACT FROM AUTHOR]

Coordination compounds are well‐known compounds that are being used as new materials for lithium storage because of their unique advantages, that is, designable structures, abundant active sites, and facile as well as mild synthetic routes. However, the electrode stability, low rate performance, and cycle life of coordination compounds are currently the main issues preventing their application as electrode materials, and the lithium‐storage mechanism in coordination networks is not well understood. Herein, isostructural one‐dimensional coordination compounds were synthesized to study their lithium‐storage performance. Co‐HIPA and Ni‐HIPA showed superior electrolyte stability than other M‐HIPAs, and Co‐HIPA displayed a superior reversible capacity and cycle stability, excellent rate performance, and clear voltage platform. DFT calculations and kinetic analysis revealed the influence of the metal center with different electronic structures on the lithium‐storage mechanism. [ABSTRACT FROM AUTHOR]

Here, it is shown for the first time that alloxazine (ALO) can reversibly store hydronium ions in 1 M Mg(NO3)2 electrolyte. Comprehensive analyses confirm that Mg2+ ions, which possess catalytic properties, can promote hydronium-ion transfer by forming a stable complex with reducing ALO. [ABSTRACT FROM AUTHOR]

Purpose: The surface‐matching registration method in the current neuronavigation completes the coarse registration mainly by manually selecting anatomical landmarks, which increases the registration time, makes the automatic registration impossible and sometimes results in mismatch. It may be more practical to use a fast, accurate, and automatic spatial registration method for the patient‐to‐image registration. Methods: A coarse‐to‐fine spatial registration method to automatically register the patient space to the image space without placing any markers on the head of the patient was proposed. Three‐dimensional (3D) keypoints were extracted by 3D Harris corner detector from the point clouds in the patient and image spaces, and used as input to the 4‐points congruent sets (4PCS) algorithm which automatically registered the keypoints in the patient space with the keypoints in the image space without any assumptions about initial alignment. Coarsely aligned point clouds in the patient and image space were then fine‐registered with a variant of the iterative closest point (ICP) algorithm. Two experiments were designed based on one phantom and five patients to validate the efficiency and effectiveness of the proposed method. Results: Keypoints were extracted within 7.0 s with a minimum threshold 0.001. In the phantom experiment, the mean target registration error (TRE) of 15 targets on the surface of the elastic phantom in the five experiments was 1.17 ± 0.04 mm, and the average registration time was 17.4 s. In the clinical experiments, the mean TRE of the targets on the first, second, third, fourth, and fifth patient's head surface were 1.70 ± 0.32 mm, 1.83 ± 0.38 mm, 1.64 ± 0.3 mm, 1.67 ± 0.35 mm, and 1.72 ± 0.31 mm, respectively, and the average registration time was 21.4 s. Compared with the method only based on the 4PCS and ICP algorithm and the current clinical method, the proposed method has obvious speed advantage while ensuring the registration accuracy. Conclusions: The proposed method greatly improves the registration speed while guaranteeing the equivalent or higher registration accuracy, and avoids a tedious manual process for the coarse registration. [ABSTRACT FROM AUTHOR]

A series of potential chiral compounds containing an α,β-unsaturated ketone was developed for anion detection. The interplay of compounds and biological momentous anions (Cl−, H2PO4−, I−, AcO−, HS−, F−, and Br−) was evaluated by UV-vis experiments, fluorescence experiments, and electrochemical tests. By comparison, compound 1 had the best selectivity and compound 5 had the strongest binding ability among the five compounds. And compound 5 had the highest sensitivity to H2PO4− among the measured anions, and it also can be applied to actual samples, the content of H2PO4− tested in the potassium dihydrogen phosphate fertilizer solution reached above 97.5% of the marked content, and the recovery rates were within the range of 98.5–99.1%, attesting that this method was reliable for the test of H2PO4− in fertilizer. Through HRMS titration, circular dichroism and optical rotation experiments, the probable interacted mechanism was proved that the interaction site was the C=C of the α,β-unsaturated ketone structure. In addition, the interacted mechanism was researched from the perspective of chirality. Furthermore, theoretical investigation analysis was introduced to reveal that the roles of molecular frontier orbitals in molecular interplay were determined. Therefore, this series of potential chiral compounds has potential application prospects in anion recognition. [ABSTRACT FROM AUTHOR]

Pyrophosphate (PPi) is a significant biological anion, and its abnormal level in the human body is regarded as a signal of some diseases. Herein, we developed a method for the detection of PPi using a luminescent ZTMOF-1 via the luminescence turn-on effect. PPi formed hydrogen bonds with the phenyl and pyridine rings in the framework, and ZTMOF-1 could discriminately detect PPi among other phosphorus oxides in both an aqueous solution and a physiological environment. In addition, to the best of our knowledge, this is the first report on the use of a regenerable MOF-based luminescent sensor for the detection of PPi. Moreover, ZTMOF-1 showed an excellent luminescence quenching response to nitrofurantoin (NFT) over other drugs with the detection limit of 0.175 μM. This study presents a dual-responsive regenerable luminescent probe for the detection of PPi and NFT. [ABSTRACT FROM AUTHOR]

Abstract: A silver‐promoted oxidative benzylic C−H trifluoromethoxylation has been reported for the first time. With trifluoromethyl arylsulfonate as the trifluoromethoxylation reagent, various arenes, having diverse functional groups, undergo trifluoromethoxylation of their benzylic C−H bonds to form trifluoromethyl ethers under mild reaction conditions. In addition, the trifluoromethoxylation and the fluorination of methyl groups of electron‐rich arenes have been achieved to prepare α‐fluorobenzyl trifluoromethyl ethers in one step. [ABSTRACT FROM AUTHOR]

Abstract: A silver‐promoted oxidative benzylic C−H trifluoromethoxylation has been reported for the first time. With trifluoromethyl arylsulfonate as the trifluoromethoxylation reagent, various arenes, having diverse functional groups, undergo trifluoromethoxylation of their benzylic C−H bonds to form trifluoromethyl ethers under mild reaction conditions. In addition, the trifluoromethoxylation and the fluorination of methyl groups of electron‐rich arenes have been achieved to prepare α‐fluorobenzyl trifluoromethyl ethers in one step. [ABSTRACT FROM AUTHOR]

Inspired by biological related parts, Schiff base derivatives and functional groups of chemical modification can provide efficient detection method of amino acids. Therefore, we have designed and prepared 4 compounds based on Schiff base derivatives involving ─NO2, ─OH, and naphthyl group. Results indicated that compound 4 containing 2 nitro groups showed strong sensitivity and high selectivity for arginine (Arg) among normal 18 kinds of standard amino acids (alanine, valine, leucine, isoleucine, methionine, aspartic acid, glutamic acid, arginine, glycine, serine, asparagine, phenylalanine, histidine, tryptophan, proline, lysine, glutamine, and cysteine). Theoretical investigation also approved the strong binding ability of compound 4 for Arg. In addition, compound 4 displayed high combining ability of Arg and low cytotoxicity of MCF-7 cell in the 0 to 150 μg mL−1 of concentration range; it can be used for Arg in vivo detection of fluorescent probe. [ABSTRACT FROM AUTHOR]

Abstract: Tunable photoluminescence nanomaterials have aroused increasing interest from researchers recently due to their application in bioimaging, photodynamic therapy, and energy conversion. Herein, an artificial ternary nanosystem comprised of dithienylethene‐bridged bis(permethyl‐β‐CD)s, dodecyl‐bearing porphyrin, and amphipathic near‐infrared (NIR) cyanine fluorochrome is conveniently constructed by rationally designing the host/guest components, dimensions, and properties. In this system, an effective energy transfer (ET) from porphyrin to cyanine fluorochrome leads to the dramatic enhancement of NIR fluorescence intensity and more crucially, this process can be efficiently regulated by distinct light input, achieving photoswitching ET‐NIR fluorescence in aqueous media. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed activation of remote meta-C−H bonds in arenes containing tethered alcohols was achieved with high regioselectivity by using a nitrile template. Computational studies on the macrocyclic transition state of the regioselectivity-determining C−H activation steps revealed that both the C-N-Ag angles and gauche comformations of phenyl ether play an extremely important role in the meta selectivity. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed activation of remote meta-C−H bonds in arenes containing tethered alcohols was achieved with high regioselectivity by using a nitrile template. Computational studies on the macrocyclic transition state of the regioselectivity-determining C−H activation steps revealed that both the C-N-Ag angles and gauche comformations of phenyl ether play an extremely important role in the meta selectivity. [ABSTRACT FROM AUTHOR]

Based on a coordination symmetry approach, a luminescent lanthanide metal–organic framework (Ln-MOF), {[Eu2(L)3(DMF)2]·DMF·MeOH}n (Ln-MOF 1, H2L = 5-(4H-1,2,4-triazol-4-yl)benzene-1,3-dicarboxylic acid), with a 3,8-connected tfz-d net was synthesized. Ln-MOF 1 exhibits a strong red luminescence induced by the efficient antenna effect of the ligand. More importantly, Ln-MOF 1 luminescence is efficiently quenched upon exposure to polychlorinated benzenes, which are persistent organic pollutants (POPs) and cause permanent damage to human health and living environments. [ABSTRACT FROM AUTHOR]

Front Cover: Hydrogen-bonded Complex-based Frameworks for Stable Lithium Storage (Chem. Lithium-ion battery, Metal-organic complex, Hydrogen-bonded framework, Dimensional design Keywords: Lithium-ion battery; Metal-organic complex; Hydrogen-bonded framework; Dimensional design EN Lithium-ion battery Metal-organic complex Hydrogen-bonded framework Dimensional design 1 1 1 07/05/23 20230703 NES 230703 B Hydrogen-bonded complex-based frameworks b were applied for the development of high-performance anode materials of lithium-ion batteries. [Extracted from the article]

The first example of a hypervalent iodine(III)-mediated oxidative fluorination of alkylsilanes by fluoride ions without the use of transition metals is demonstrated. This reaction is operationally simple, scalable, and proceeds under mild reaction conditions. Mechanistic studies suggest the involvement of a single-electron transfer resulting from the interaction of an organopentafluorosilicate and aryliodonium difluoride, which were generated in situ from the corresponding alkylsilane and iodosobenzene, respectively, in the presence of fluoride ions. [ABSTRACT FROM AUTHOR]

The first example of a hypervalent iodine(III)-mediated oxidative fluorination of alkylsilanes by fluoride ions without the use of transition metals is demonstrated. This reaction is operationally simple, scalable, and proceeds under mild reaction conditions. Mechanistic studies suggest the involvement of a single-electron transfer resulting from the interaction of an organopentafluorosilicate and aryliodonium difluoride, which were generated in situ from the corresponding alkylsilane and iodosobenzene, respectively, in the presence of fluoride ions. [ABSTRACT FROM AUTHOR]

The basic groups and some atomic groups in polynucleotide long-chains of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) have been used as the basic structural unit to analyze their molecular symmetry. The basic groups have been treated as the same structural unit in spite of the fact that they have very different intrinsic characteristics. In this paper, we developed bi-double-valued H- and P-representations to distinguish between the various structural units in DNA and RNA. We simulated their molecular symmetries based on our earlier work on the symmetry analysis of cylinder and torus carbon nanotubes. The symmetric and antisymmetric components of some gene segments with some transformations have been calculated in the bi-double-valued HP-representation space. By analyzing the genetic code table, we investigated the distributive features of codons in corresponding H- and P-representations. The results indicate that some characteristics of H- and P-representation carry messages of the corresponding genetic processes in DNA. In addition, we analyzed some topologic features and Möbius twists of torus groups for circular DNA. [ABSTRACT FROM AUTHOR]

A de novo synthesis of a benzene ring allows for the preparation of a diverse range of heterocycles including indoles, benzofurans, benzothiophenes, carbazoles, and dibenzofurans from simple heteroaryl propargylic esters using a unified carbonylative benzannulation strategy. Multiple substituents can be easily introduced to the C4-C7 positions of indoles and related heterocycles. [ABSTRACT FROM AUTHOR]

A series of water-soluble supramolecular assemblies were constructed from dithienylethene-modified permethyl-β-cyclodextrins and porphyrin derivatives, accompanied by a high FRET efficiency, and could be applied in the control of singlet oxygen generation in a 1% ethanol aqueous solution upon irradiation of different wavelength light. These findings will provide a feasible and convenient way to construct a potential photodynamic therapy material. [ABSTRACT FROM AUTHOR]

By switching the position of the alkene and alkyne, a new type of 3-acyloxy-1,4-enyne (ACE) five-carbon building block was developed for Rh-catalyzed intramolecular [5+2] cycloaddition. An electron-withdrawing acyl group on the alkyne termini of the ACE was essential for a regioselective 1,2-acyloxy migration. This new method provided bicyclic [5.3.0]decatrienes that are different from previous methods because of the positions of the alkenes and the acyloxy group. Multiple mechanistic pathways become possible for this new [5+2] cycloaddition and they are investigated by computational studies. [ABSTRACT FROM AUTHOR]

A simple colorimetric sensor, 2-bromonaphthalene-1,4-dione, has been developed for the Cysteine detection. The sensor showed its best performance in a mixture of ethanol and HEPES (5 : 5, v/v) solution at pH of 7.0. The results of UV-vis and fluorescence indicated that 2-bromonaphthalene-1,4-dione was selective and sensitive for Cysteine detection without the interference of other amino acids (Cysteine, Alanine, Arginine, Aspartinie, Glutamine, Glycine, Histidine, Isoleucine, Leucine, Lysine, Methionine, Proline, Serine, Threonine, Phenylalanine, Valine, Tryptophan, and Hydroxyproline). 2-Bromonaphthalene-1,4-dione also showed binding ability for Cysteine in bovine serum albumin and could be used as a potential colorimetric sensor among eighteen kinds of natural amino acids. Importantly, the recognition of CySH could be observed by naked eye. [ABSTRACT FROM AUTHOR]