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A simple protocol for the rapid synthesis of chalcogen-containing compounds by an I2O5-promoted oxidative Csp2–H selenation and seleno/thiocyanation of activated arenes is reported here.

A time-economical and robust synthesis of selenofunctionalized heterocycles by an I2O5-promoted selenylative heterocyclization of olefins with easily accessible diselenides is reported herein.

In this paper, the host-guest interaction of cucurbit[7]uril (Q[7]) and chromone (CMO) has been developed as a fluorescent probe for the highly selective detection of Zn2+ and Cd2+ in water based on a chelation-enhanced fluorescence (CHEF) mechanism. There was a good linear relationship between the fluorescence intensity of the CMO@Q[7] probe and the concentration of Zn2+ or Cd2+ in the range of 0–3.0 × 10–5 mol/L and the detection limit for Zn2+ and Cd2+ was found to be 2.03 × 10–6 mol/L and 1.89 × 10–6 mol/L, respectively. The X-ray crystal structure indicated that different coordination fashions were triggered by Zn2+ and Cd2+ in the CMO@Q[7] complexes, respectively. However, both metal ions coordinated with the carbonyl oxygen of CMO, which was encapsulated in the cavity of Q[7], thus leading to the enhancement of recognition fluorescence emission of CMO.

By using the method of building blocks, the dodecamethycucurbit[6]uril Me12Q[6] was synthesized and its structure was characterized by multiple techniques. The binding interactions between Me12Q[6]...

A physical impregnation method is presented in this study, providing a facile approach to encapsulating functional guest molecules (GMs) into robust crystalline supramolecular organic frameworks incorporating cucurbit[10]uril (Q[10]-SOF). As Q[10]-SOF has high evaporated pyridine affinity under normal atmospheric pressure, pyridine molecules in this method were successfully encapsulated into the nanospace formed by GMs and Q[10]-SOF while retaining their crystal framework, morphology, and high stability. GMs@Q[10]-SOF solid materials were found to respond to pyridine, being suitable to be used as solid sensors. Notably, Q[10]-SOF loading with pyrene exhibited a unique response to pyridine along with dramatic fluorescence quenching; loading with dansyl chloride exhibited a unique response to pyridine along with significant fluorescence enhancement, having a quick response within 60 s. Our findings represent a critical advancement in the design of pyridine detection and adsorption for commercial gas identification and sensing.

Curcurbit[n]uril (Q[n])-based supramolecular frameworks (QSFs) constructed from the outer surface interaction of Q[n]s (OSIQ) have the characteristic of simplicity, diversity and modulability. Their simplicity is reflected in their simple composition and preparation methods used for QSFs. The diversity of supramolecular organic frameworks (SOFs) is reflected in the synthesis methods and structural characteristics of the as-obtained QSFs, as well as the variety of structural directing agents and basic building blocks used to prepare QSFs. The modulability is reflected by the controllable channel size in the QSFs, which can be adjusted using different sizes of Q[n]s. In this work, the first reported cucurbituril Q[6] was selected as the basic building block and three Q[6]-based supramolecular frameworks were obtained from aqueous HCl solutions in the presence of [CdCl4]2− respectively. The OSIQs are the main driving forces for the formation of these frameworks. This study shows the diversity of the QSFs.

Context Salidroside, a compound extracted from Rhodiola rosea L. (Crassulaceae), possesses many beneficial pathological effects. Objective To explore the effect of salidroside on ventilator-induced lung endothelial dysfunction in vivo and in vitro. Materials and methods In vivo, male ICR mice were divided into sham, ventilation, salidroside, and ventilation plus salidroside groups. The mice were ventilated for 4 h, salidroside (50 mg/kg) was administrated intraperitoneally before ventilation, dexamethasone (Dex) (5 mg/kg) was used as a positive control. In vitro, mouse lung vascular endothelial cells (MLVECs) were treated with salidroside, MMP-9 siRNA, and BAY11-7082 (10 μM), and then exposed to cyclic stretch for 4 h. Afterward, lung tissues and MLVECs were collected for further analysis. Results Salidroside pre-treatment significantly reversed the expression of vascular endothelial cadherin (VE-cadherin) and zonula occluden-1 (ZO-1) proteins in cyclic stretch-treated MLVECs (0.46 ± 0.09 vs. 0.80 ± 0.14, 0.49 ± 0.05 vs. 0.88 ± 0.08) and ventilated lung tissues (0.56 ± 0.06 vs. 0.83 ± 0.46, 0.49 ± 0.08 vs. 0.80 ± 0.12). The results further indicated that salidroside inhibited the expression of matrix metalloproteinase-9 (MMP-9), whereas knockdown of its expression restored the expression levels of VE-cadherin (0.37 ± 0.08 vs. 0.85 ± 0.74) and ZO-1 (0.48 ± 0.08 vs. 0.81 ± 0.11) in stretched MLVECs. Meanwhile, salidroside inhibited the NF-κB signalling pathway and alleviated lung injury. Conclusions Salidroside protected against stretch-induced endothelial barrier function, improving lung injury after ventilation. Thus, salidroside may be a promising therapeutic agent for patients with MV-induced lung injury.

An intermolecular aminoselenation of alkenes with sulfonimides and diselenides is achieved via a visible-light-induced three component reaction. A broad variety of aminoselenation products is accessible in good yields with excellent functional group compatibility. Additional features of this new protocol include being additive- and photocatalyst-free and the use of natural sunlight as well as suitability for the modification of styrene-functionalized biomolecules. Mechanistic investigations suggest that the transformation occurs through a sequence of radical additions and nucleophilic substitutions.

Cucurbit[n]uril(Q[n])-based supramolecular frameworks assembled through outer surface interactions are characterized by their simple composition, convenient preparation, high yields and controllable structures. The most prominent characteristic of these frameworks is their diversity, with various synthesis methods, structural characteristics, structure directing agents and basic building blocks of Q[n]s. In this work, a symmetric tetramethyl-substituted Q[6] (TMeQ[6]) is selected as the basic building block, with three different TMeQ[6]-based supramolecular frameworks obtained from 1-, 3- and 5 mol/L aqueous H2SO4 solutions, respectively. The outer surface interactions between TMeQ[6] and the adjacent SO42− anions or TMeQ[6] units are the main driving forces for the formation of these frameworks, which exhibit adsorption properties for fluorophore dyes and organic isomers. These adsorption characteristics may lead to the application of these frameworks in the synthesis of solid fluorescent sensors for volatile organic compounds and the adsorptive separation of alkane isomers.

The development of cucurbit[n]urils–polyoxometalate (Q[n]–POM) hybrids with the same microshape and nanoscale features is highly desirable, yet remains a great challenge. Herein, we design and synthesize a class of Q[n]–POM hybrids and tetramethyl cucurbit[6]uril–phosphomolybdic acid (TMeQ[6]–PMA) nanocubes (NCs) via a facile one-step self-assembly method, as heterogeneous acid catalysts for greatly boosting the catalysts in term of activity and stability for the esterification of gallic acid and n-propanol to propyl gallate (PG). The Fourier transform infrared (FTIR) spectroscopy reveals that the self-assembled mechanism of TMeQ[6]–PMA NCs based on the outer-surface interaction of Q[n]s. The temperature programmed desorption experiments with ammonia and FTIR analysis of the pre-adsorbed pyridine results confirm that the coexistence of medium and strong acid sites and a larger number of Lewis acid sites other than Bronsted acidic sites on the catalyst surface. These new features make the as-prepared TMeQ[6]–PMA NCs exhibit a high PG conversion (95.6%) and excellent stability, which represents a better catalytic performance than other reported catalysts.

A time-economical and robust synthesis of various selenofunctionalized heterocycles was accomplished

Atypical luminescent compounds that do not contain conventional chromophores emit light due to clustering and have important basic research value and a broad range of potential applications. To date, most atypical luminescent compounds are small molecules or polymers containing groups such as cyano, carbonyl and hydroxyl. In this work, driven by some sporadic and accidental luminescence phenomena observed for cucurbit[n]urils (Q[n]s), the luminescent properties and mechanism of Q[n]s in the solid- and solution-state were systematically studied and the clustering emission of Q[n]s confirmed. Our experiments have revealed that the self-induced outer-surface interactions of Q[n]s (OSIQ) are the most important driving force resulting in the clustering emission of Q[n]s. Substances that can weaken the effect of self-induced OSIQ, such as the presence of various aromatic compounds and anions, may weaken or quench the clustering emission of Q[n]s. This not only reveals the new characteristics and mechanism of the clustering emission of Q[n]s, but also provides new insights on how to utilize the clustering emission of Q[n]s and construct new types of macrocyclic luminescence systems.

The coordination of alkaline earth metal cations (AE2+ = Mg2+, Ca2+, Sr2+, Ba2+) with inverted hexamethylcucurbit[3,3]uril {iMe6Q[3,3]} has been investigated in the presence of polychlorido cadmium anions as structure directing agent. Single-crystal X-ray diffraction analysis has revealed that the interactions of iMe6Q[3,3] with AE2+ cations result in the formation of linear iMe6Q[3,3]-based coordination polymers from iMe6Q[3,3]-AECl2-CdCl2-HCl systems. Generally, Cd2+ cations can form [CdCl4]2− anions that serve as structure directing agent in the formation of iMe6Q[3,3]/AE2+-based coordination polymers. Moreover, iMe6Q[3,3]-AECl2-CdCl2-HCl systems exhibit high affinity for the heavier AE2+, such as Sr2+, and Ba2+.

Herein, we report the facile preparation of two solid luminescent materials made from cucurbit[10]uril-based porous supramolecular assemblies, from simple precipitation of cucurbit[10]uril (Q[10]) in HCl solution (A) or HNO3 solution (B). Loading Q[10]-based porous supramolecular assemblies A or B with various fluorophore guests (FGs), including dyes and fused ring compounds, to yield solid luminescent materials (FG@As and FG@Bs) that exhibited fluorescence enhancement or colour changing fluorescence emission. Moreover, these solid luminescent materials could respond to certain volatile organic compounds, demonstrating promise as solid sensors.

We report herein a cucurbit[10]uril-based porous supramolecular assembly (A) that is readily obtained in the presence of [ZnCl4]2− as a structure-directing agent in HCl solution. Loading the Q[10]-based porous supramolecular assembly A with various fluorophore guests, including various dyes and fused-ring compounds, yielded solid luminescent materials showing fluorescence enhancement or quenching or emission color change. Moreover, these solid luminescent materials could respond to certain volatile organic compounds. In particular, the assembly obtained by loading A with 1,8-diaminonaphthalene exhibited a distinct response to formaldehyde and could be used as a solid sensor.

Q[8]-based honeycomb-like frameworks can be obtained in [AuCl4]--free aqueous HNO3 solution and aqueous HCl and HNO3 solutions that contain [AuCl4]-. The outer surface interaction of Q[8] with planar inorganic anions [AuCl4]- and NO3- is the main driving force. These frameworks exhibit a high selectivity for imprisoning [AuCl4]- that could establish a process for gold recovery.

Owing to narrow energy band of \textit{Swift}/BAT, several urgent issues are required to pay more attentions but unsolved so far. We systematically study the properties of a refined sample of 283 \textit{Swift}/BAT gamma-ray bursts with well-measured spectral peak energy ($E_{\text p}$) at a high confidence level larger than 3$\sigma$. It is interestingly found that duration ($T_{90}$) distribution of \textit{Swift} bursts still exhibits an evident bimodality with a more reliable boundary of $T_{90}\simeq$1.06 s instead of 2 s for previously contaminated samples including bursts without well-peaked spectra, which is very close to $\sim$1.27 s and $\sim$0.8 s suggested by some authors for Fermi/GBM and \textit{Swift}/BAT catalogs, respectively. The \textit{Swift}/BAT short and long bursts have comparable mean $E_{\text p}$ values of $87^{+112}_{-49}$ and $85^{+101}_{-46}$ keV in each, similar to what found for both types of BATSE bursts, which manifests the traditional short-hard/long-soft scheme may not be tenable for the certain energy window of a detector. In statistics, we also investigate the consistency of distinct methods for the $E_{\text p}$ estimates and find that Bayesian approach and BAND function can always give consistent evaluations. In contrast, the frequently-used cut-off power-law model matches two other methods for lower $E_{\text p}$ and will overestimate the $E_{\text p}$ more than 70\% as $E_{\text p}>$100 keV. Peak energies of X-ray flashes, X-ray rich bursts and classical gamma-ray bursts could have an evolutionary consequence from thermal-dominated to non-thermal-dominated radiation mechanisms. Finally, we find that the $E_{\text p}$ and the observed fluence ($S_{\gamma}$) in the observer frame are correlated as $E_p\simeq [S_{\gamma}/(10^{-5} erg\ cm^{-2})]^{0.28}\times 117.5^{+44.7}_{-32.4}$ keV proposed to be an useful indicator of GRB peak energies., Comment: 25 pages; 7 figures; 2 tables. Accepted for publication in ApJ

Mechanical ventilation (MV) and lipopolysaccharide (LPS) infection are common causes of acute lung injury. The aim of the present study was to identify the key genes and potential mechanisms involved in mechanical ventilation (MV) and lipopolysaccharide (LPS)-induced acute lung injury (ALI). Gene expression data of adult C57BL/6 mice with ALI induced by inhaling LPS, MV and LPS + MV were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) associated with MV, LPS and LPS + MV were screened, followed by functional enrichment analysis, protein-protein interaction network construction, and prediction of transcription factors and small molecule drugs. Finally, the expression of key genes was verified in vivo using reverse transcription-quantitative PCR. A total of 63, 538 and 1,635 DEGs were associated with MV, LPS and LPS + MV, respectively. MV-associated genes were significantly enriched in the ‘purine ribonucleotide metabolic process’. LPS and LPS + MV-associated genes were significantly enriched in ‘cellular response to cytokine stimulus’ and ‘cell chemotaxis’. All three conditions were enriched in ‘TNF signaling pathway’ and ‘IL-17 signaling pathway’. Expression levels of C-X-C motif chemokine ligand (CXCL)2, CXCL3 and CXCL10 were upregulated in the LPS and LPS + MV groups. Adenosine A2b receptor, zinc finger and BTB domain-containing 16 and hydroxycarboxylic acid receptor 2 were identified as DEGs in the MV group. Compared with the control group, Early growth response 1 and activating TF 3 was upregulated in all three groups. Similarities and differences were observed among the MV- and LPS-induced ALI, and MV may enhance the effects of LPS on gene expression. MV may affect urine ribonucleotide metabolic-related processes, whereas LPS may cause cell chemotaxis and cytokine stimulus responses in ALI progression. The inflammatory response was shared by MV and LPS. The results of the present study may provide insight into a theoretical basis for the study and treatment of ALI.

In the present work, we selected hexamethylcucurbit[3,3]uril (Me6Q[3,3]) as a building block and obtained two Me6Q[3,3]-based porous supramolecular assemblies from neutral water (A) and aqueous HCl solutions (B), respectively. Both Me6Q[3,3]-based assemblies are constructed of Me6Q[3,3] molecules through the typical outer surface interaction of cucurbit[n]urils, as well as hydrogen bonding between latticed water molecules and portal carbonyl oxygens of Me6Q[3,3]. The assemblies present different porous structure features and exhibit different adsorption properties for eight common volatile organic compounds. However, the two porous assemblies exhibit similar adsorption properties for certain fluorophore dyes, including rhodamine B (G1), fluorescein (G2), and pyrene (G3), and form solid colored fluorescent compounds, some of which exhibit responses to the selected volatile organic compounds.

Two perhydroxylated cucurbit[6]uril-based supramolecular assemblies have been obtained via crystallization of perhydroxylated cucurbit[6]uril {(HO)12Q[6]} from aqueous HCl solutions of different concentrations. Single-crystal X-ray diffraction (unit cell) analysis revealed that (HO)12Q[6] molecules interacted with water molecules through hydrogen bonding, thereby forming solid supramolecular assemblies with different kinds of channels. These selected channels were formed from the stacking of (HO)12Q[6] molecules in a portal-to-portal manner and between the outer surfaces of (HO)12Q[6] molecules. Unlike normal or alkyl-substituted Q[n]-based supramolecular assemblies, which generally exhibit highly selective absorption of methanol, the (HO)12Q[6]-based supramolecular assemblies exhibit highly selective absorption of polychloromethanes.