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Large scale synthesis of cycloparaphenyleneacetylenes has been challenging due to low macrocyclization yields and harsh aromatization methods that often decompose strained alkynes. Herein, a cis-stilbene-based building block is subjected to alkyne metathesis macrocylization. The following sequence of alkene-selective bromination and dehydrobromination afforded a [8]cycloparaphenyleneacetylene derivative in high yield with good scalability. X-Ray crystal structure and computational analysis revealed a unique same-rim conformation for the eight methyl groups on the nanohoop. [ABSTRACT FROM AUTHOR]

Radical fluoroalkylation of alkenes has been developed by electrochemical reduction of fluoroalkyl sulfones. A series of electron-deficient alkenes readily undergo hydrofluoroalkylation in good to excellent yields. This chemistry represents the first example of electrochemical generation of fluoroalkyl radicals from sulfones, which are used for practical radical fluoroalkylation of organic compounds. [ABSTRACT FROM AUTHOR]

Herein, we report a photoinduced selective perfluoroalkylation of terminal alkynes driven by the noncovalent interaction between a thymol anion and fluoroalkyl iodides. By precisely tuning the reaction solvent, a wide range of 37 structurally diverse perfluoroalkylated alkynes and alkenes, including ibuprofen, empagliflozin, galactose, isoxepac and indomethacin, were obtained in up to 92% yields. Mechanistic studies reveal the formation of EDA complexes between the thymol anion and fluoroalkyl iodides. This strategy may provide an important complement to traditional approaches to prepare useful perfluoroalkylated alkynes and alkenes. [ABSTRACT FROM AUTHOR]

A two-dimensional covalent organic framework (2D COF), synthesized on a highly oriented pyrolytic graphite (HOPG) surface with benzene-1,3,5-tricarbaldehyde and p-phenylenediamine as the precursors, is used as a host to accommodate three guest molecules, coronene, copper phthalocyanine (CuPc), and fluorine-substituted copper phthalocyanine (F16CuPc). The host–guest interaction and dynamic behavior were investigated by scanning tunneling microscopy and density functional theory. [ABSTRACT FROM AUTHOR]

Herein, a novel strategy is presented for the photoinduced decarboxylative and dehydrogenative cross-coupling of a wide range of α-fluoroacrylic acids with hydrogermanes. This methodology provides an efficient and robust approach for producing various germylated monofluoroalkenes with excellent stereoselectivity within a brief photoirradiation period. The feasibility of this reaction has been demonstrated through gram-scale reaction, conversion of germylated monofluoroalkenes, and modification of complex organic molecules. [ABSTRACT FROM AUTHOR]

A new water-soluble receptor 1has been synthesized and it showed selective recognition of zwitterionic arginine in aqueous media. Moreover, the receptor 1could be regard as a facile tool for protein labeling and quantitative determination (LOD= 15 nM). [ABSTRACT FROM AUTHOR]

Unprecedented, oxygen defect-rich, monoclinic BiVO4 nanotubes with largely exposed active {010} facets were successfully fabricated through a self-curling process of nascently generated ultrathin lamellar sheets, exhibiting impressive photocatalytic performance for both water oxidation and the selective N=N coupling reaction of 5-amino-1H-tetrazole into sodium 5,5-azotetrazolate, with more than an order of magnitude enhancement relative to bulk materials. [ABSTRACT FROM AUTHOR]

Three-dimensional ordered mesoporous polymer (OMP) single-crystals were synthesized for the first time via a simple soft-template strategy. Ordered mesoporous nitrogen-doped carbon (OMNC) was obtained through carbonization of OMP and post ammonia activation. The evolution of specific surface area, pore volume, and nitrogen content, and species of OMNC were systematically investigated by adjusting the activation temperature and time. [ABSTRACT FROM AUTHOR]

Type I photodynamic therapy (PDT) with less oxygen consumption shows great potential to overcome the malignant hypoxia in solid tumors. Herein, a novel meso phosphate-substituted pyronin PY-P and its nanoparticles (PY-P NPs) were prepared as an efficient type I organic photosensitizer. The in vivo data prove that PY-P NPs have outstanding low dark toxicity but high photocytotoxicity under hypoxia (<1% O2). [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is known to play a key role in the modulation of the redox environment in N-methyl-d-aspartate (NMDA) receptors. Coumarin derivative 1 bearing cyanoacrylamide and ifenprodil moieties was synthesized and reported to monitor GSH near NMDA receptors. The cyanoacrylamide moiety allows probe 1 to monitor GSH reversibly at pH 7.4 and the ifenprodil group acts as a directing group for NMDA receptors. Two-photon fluorescence microscopy allows probe 1 to successfully sense endogenous GSH in neuronal cells and hippocampal tissues with excitation at 750 nm. Furthermore, the addition of H2O2 and GSH induced a decrease and an increase in fluorescence emission. Probe 1 can serve as a potential practical imaging tool to get important information on GSH in the brain. [ABSTRACT FROM AUTHOR]

We have designed and synthesized two porphyrin containing two-dimensional (2D) polymers based on the imine linkage. Both the 2D polymers are revealed to be 2D organic semiconductors with band gaps of around 1 eV. STM characterization reveals that the rigidity and affinity of building blocks to the surface has essential effects on the topology of the 2D polymers. [ABSTRACT FROM AUTHOR]

As a versatile quantification and tracking technology, 19F magnetic resonance imaging (19F MRI) provides quantitative "hot-spot" images without ionizing radiation, tissue depth limit, and background interference. However, the lack of suitable imaging agents severely hampers its clinical application. First, because the 19F signals are solely originated from imaging agents, the relatively low sensitivity of MRI technology requires high local 19F concentrations to generate images, which are often beyond the reach of many 19F MRI agents. Second, the peculiar physicochemical properties of many fluorinated compounds usually lead to low 19F signal intensity, tedious formulation, severe organ retention, etc. Therefore, the development of 19F MRI agents with high sensitivity and with suitable physicochemical and biological properties is of great importance. To this end, perfluoro-tert-butanol (PFTB), containing nine equivalent 19F and a modifiable hydroxyl group, has outperformed most perfluorocarbons as a valuable building block for high performance 19F MRI agents. Herein, we summarize the development and application of PFTB-based 19F MRI agents and analyze the strategies to improve their sensitivity and physicochemical and biological properties. In the context of PFC-based 19F MRI agents, we also discuss the challenges and prospects of PFTB-based 19F MRI agents. [ABSTRACT FROM AUTHOR]

The first fluorooxoborate with reversible phase transition, BaB4O5F4, has been obtained. Interestingly, the two polymorphs, α- and β-BaB4O5F4 with rare [BOF3], feature various one-dimensional chains composed of the unprecedented fundamental building blocks of [B16O21F16] and [B4O6F4], respectively. First-principles calculations were performed to elucidate the structure–property relationships. [ABSTRACT FROM AUTHOR]

A new non-encapsulated fluorinated liposome (TSL) was developed, which showed instantaneous temperature-induced 19F MR signal enhancement and excellent stability under reversible signal transition at different conditions. [ABSTRACT FROM AUTHOR]

Glycerol is selectively converted to hydroxyacetaldehyde (HAA) and H2 in aqueous solution on TiO2-based photocatalysts. The product selectivity was verified to be strongly dependent on the facets of TiO2. Rutile with high percentage of {110} facets results in over 90% superior selectivity of HAA, while anatase with {001} or {101} facets gives only 16% and 49% selectivity for HAA, respectively. [ABSTRACT FROM AUTHOR]

We for the first time report that the activated CRISPR-Cas12a system trans-cleaves DNA G-quadruplexes (G4). The cleavage activity on human telomere G4 and TBA G4 was investigated and verified by FRET, CD, gel electrophoresis and NMR. We believe that this finding will pave a new avenue for advancing the applications of CRISPR-Cas12a and G4 in biosensing and biochemistry. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of tetrahydroisoquinolines bearing an all-carbon quaternary stereogenic center, was achieved via asymmetric C–H activation with high enantioselectivities (up to 93% ee). Fair substrate tolerance was indicated throughout the scope investigation and no evident loss of enantioselectivity was exhibited in late-stage derivatization. This study provides incentives for the construction of diverse chiral isoquinoline derivatives, which are prevalent among pharmaceuticals, natural products, etc. [ABSTRACT FROM AUTHOR]

Herein, we developed fluorinated nanoemulsions with significantly enhanced in vitro and in vivo129Xe hyper-CEST MRI, 19F MRI and fluorescence imaging signals for selective and sensitive tumor detection and NIR-activated photodynamic therapy. [ABSTRACT FROM AUTHOR]

In minerals and artificial crystals, the OH and F groups often coexist and have a high probability of disordered structure. The OH/F position cannot be determined accurately in the crystal structure only by the direct X-ray diffraction method because of the poor contrast between O and F and the weak diffractivity of hydrogen atoms. In this work, a new fluorooxoborate Ba[B2OF3(OH)2]2, with a size of up to 12 × 4 × 3 mm3, has been synthesized successfully by a facile hydrothermal reaction. The BOF3 units with well-ordered OH/F positions are observed for the first time in alkali/alkaline earth metal fluorooxoborates. Owing to the selective fluorination of BO4, Ba(B2OF3(OH)2)2 exhibits a large birefringence and hence can be used as a DUV birefringent material. This work will guide the study of the structural chemistry of oxyfluorides. [ABSTRACT FROM AUTHOR]

A fluorinated aza-BODIPY derivative BDPF was developed as a small molecule contrast agent, which displayed highly efficient near infrared fluorescence/photoacoustic/19F MR tri-modality tumor imaging. [ABSTRACT FROM AUTHOR]

A highly symmetrical, 24-faceted, concave BiVO4 polyhedron was fabricated, bounded by multiple high-index {012}, {210}, {115}, and {511} facets, exhibiting impressive photocatalytic O2 evolution for water oxidation in the absence of any cocatalysts, more than two orders of magnitude higher than that of the bulk materials. The corresponding apparent quantum yield (AQY) of O2 evolution was measured as high as 30.7% under 420 nm light irradiation, a new record AQY for BiVO4. The high-index facets are not only energetically favorable for water dissociation, but also exhibit an obvious reduction in the overpotential (0.7–1.0 V) for the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Here, a novel method was developed for suppressing 129Xe signals in cucurbit[6]uril (CB6) until the trigger is activated by a specific enzyme. Due to its noncovalent interactions with amino-groups and CB6, putrescine dihydrochloride (Put) was chosen for blocking interactions between 129Xe and CB6. Upon adding diamine oxidase (DAO), Put was released from CB6 and a 129Xe@CB6 Hyper-CEST signal emerged. This proposed 129Xe biosensor was then tested in small intestinal villus epithelial cells. [ABSTRACT FROM AUTHOR]

As a promising cell tracking technology, 19F MRI suffers from low sensitivity. Here, fluorinated nanoemulsions with a unified 19F signal and paramagnetic relaxation enhancement were developed as 19F MRI cellular tracers with high stability, size controllability, biocompatibility, cellular uptake, and dual-modality for sensitive in vivo RAW264.7 cell tracking. [ABSTRACT FROM AUTHOR]

Tracking drugs with 19F MRI would be beneficial for developing theranostics and optimizing drug therapy. To this end, a fluorinated dendritic amphiphile with high 19F MRI sensitivity and biocompatibility has been developed for 19F MRI tracking of doxorubicin (DOX)-loaded liposomes in mice, which may provide an effective platform to in vivo trace various drugs with 19F MRI. [ABSTRACT FROM AUTHOR]

Correction for 'Rational design of a meso phosphate-substituted pyronin as a type I photosensitizer for photodynamic therapy' by Yong Wang et al., Chem. Commun., 2022, 58, 7797–7800, https://doi.org/10.1039/D2CC02124B. [ABSTRACT FROM AUTHOR]

Salinomycin is a promising anti-cancer agent which selectively targets cancer stem cells. To improve its potency and selectivity, an analog library of salinomycin was generated by site-specific modification and CuAAc derivatization. Through a cytotoxicity analysis of the library, a fluorinated analog with high potency, selectivity, and 19F MRI sensitivity was discovered as a novel theranostic agent. [ABSTRACT FROM AUTHOR]

A novel thermo-sensitive micelle contrast agent and its enhancement of MRI contrast with temperature are reported. The morphology changes sharply near 37 °C, resulting in a significant amplification of the CEST signal. This enables detection of small changes in body temperature. [ABSTRACT FROM AUTHOR]

Novel pH-triggered nanoprobe were fabricated for 19F MRI and fluorescence imaging (MRI-FI) of cancer cells. The biocompatibility, durability, high internalizing efficiency and pore architecture justify the Au-fluorescent mesoporous silica nanoparticles as ideal, highly sensitive and highly specific vectors for 19F MRI and FI of cancer cells. [ABSTRACT FROM AUTHOR]

Here, we first demonstrated that 5-MedCTP could be incorporated into the synthetic DNA template by the exonuclease deficient Klenow fragment with a much higher efficiency than dCTP and 5-hydroxymethyl-dCTP. Further, we first conducted a comparable study of primer extension reaction using templates containing deoxycytidine (dC) or 5-methyldeoxycytidine (5-mdC) for incorporating different triphosphates. Based on our findings, 5-methyldeoxycytidine could enhance the substrate activity of the Klenow fragment (exo-) and this feature could potentially be used in DNA methylation analysis. [ABSTRACT FROM AUTHOR]

We have conducted the first systematic investigation of DNAs with modified cytosines, including 5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC), under hot alkali treatment. [ABSTRACT FROM AUTHOR]

The present study demonstrated a highly sensitive strategy for measuring telomerase activity in cell extracts. Furthermore, we applied the new strategy for in situ detection of telomerase at the cellular level in cancer cells, together with a normal cell as the negative control. [ABSTRACT FROM AUTHOR]

We reported an efficient strategy based on a strand displacement amplification for serum miRNA detection. In such a system, a multiplexed, sensitive and quick detection of miRNAs could be achieved through a combination of fluorescence labeled probes, a common primer and a polymerase. This could be potentially used in the clinical field to achieve early disease diagnosis and prognosis. [ABSTRACT FROM AUTHOR]

Correction for ‘Discovery of a 19F MRI sensitive salinomycin derivative with high cytotoxicity towards cancer cells’ by Qiuyan Shi et al., Chem. Commun., 2016, 52, 5136–5139. [ABSTRACT FROM AUTHOR]