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The development of new sustainable catalytic conversion methods of carbon dioxide (CO2) is of great interest in the synthesis of valuable chemicals. N-formylation of CO2 with amine nucleophiles as substrates has been studied in depth. The key to benign formylation is to select a suitable reducing agent to activate CO2. This paper showcases the activation modes of CO2 and the construction strategies of sustainable and catalyst-free N-formylation systems. The research progress of catalyst-free N-formylation of amines and CO2 is reviewed. There are two broad prominent categories, namely reductive amidation of CO2 facilitated by organic solvents and ionic liquids in the presence of hydrosilane. Attention is also paid to discussing the involved reaction mechanism with practical applications and identifying the remaining challenges in this field.

Lignocellulosic biomass is a promising feedstock for the synthesis of value-added chemicals and biofuels. However, one of the biggest challenges for producing high-quality diesel fuels is the lack of sufficient carbon-chain length in biomass derivatives. In this study, a C17 diesel precursor 1,1,1-tris(5-methyl-2-furyl)ethane (TEMF) with a yield of ca. 70% was synthesized from the cascade acetylation-hydroxyalkylation/alkylation of bio-based 2-methylfuran (MF) with acetic anhydride (AA) catalyzed by acid-treated montmorillonite with enhanced acidity and improved porosity. The catalytic mechanism of the cascade reaction process was investigated over different types of acid species (Bronsted acid and Lewis acid), and the influence of in situ formed acetic acid was also examined. A synergistic effect was observed to enable the synthesis of TEMF from the trimerization of MF with AA, in which Lewis acid and weak Bronsted acid species mainly catalyze the acetylation and hydroxyalkylation processes, while the subsequent alkylation step is mainly catalyzed by strong Bronsted acid.

Metal-free direct α-C(sp3)−H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is described. This novel strategy provides a facile and efficient method to access important 1,3-benzooxathiin-4-one derivatives with good functional groups tolerance and yields.

The design and construction of an artificial light-harvesting system in water by mimicking the energy transfer cascade in natural photosynthesis are of significant importance. Herein, we report an efficient two-step sequential energy transfer system based on quadruple hydrogen-bonded supramolecular polymeric nanoparticles. By loading two types of hydrophobic dyes as energy acceptors, excitation energy from the supramolecular polymer could be funneled efficiently to the final acceptor through the relay acceptor. The system exhibits tunable multicolor emission from blue through yellow to red, as well as white light emission.

The direct acyloxyation of 2-(alkylthio)benzamide has been established via the amide-assisted α-C(sp3)–H functionalization in the presence of Selectfluor by employing simple carboxylic acid and its corresponding salt as acyloxy sources. This novel and simple method is characterized by its broad substrate scope in moderate to good yields and excellent functional group compatibility. Furthermore, this method also provides a complementary strategy to access important α-acyloxy sulfides and their derivatives.

Chemocatalytic upgrading of the greenhouse gas CO2 to valuable chemicals and biofuels has attracted broad attention in recent years. Among the reported approaches, N-formylation of CO2 with an amine is of great significance due to its versatility in the construction of N-containing linear and cyclic skeletons. Herein, a stable N-heterocyclic carbene-carboxyl adduct (NHC-CO2) was facilely prepared and could be used as a recyclable zwitterionic catalyst for efficient CO2 reductive upgrading via either N-formylation or further coupling with cyclization under mild conditions (25 °C, 1 atm CO2) using hydrosilane as a hydrogen source. More than 30 different alkyl and aromatic amines could be transformed into the corresponding formamides or benzimidazoles with remarkable yields (74%–98%). The electronic effect of the introduced substituent on NHC-CO2 was found to evidently affect the thermostability and nucleophilicity of the zwitterionic catalyst, which is directly correlated with its catalytic activity. Moreover, NHC-CO2 could supply CO2 by in situ decarboxylation at a specific temperature that is dependent on the introduced substituent type. Experimental and computational studies showed that the carboxyl species on NHC-CO2 was not only a nucleophilic center, but also a C1 source which rapidly captures or substitutes ambient CO2 during hydrosilylation. In addition, a simple and green conceptual process was designed for the product purification and catalyst recycling, with a good feasibility for small-scale production.

A novel upper-rim functionalized calix[4]squaramide organocatalyst bearing bis-squaramide and cyclohexanediamine scaffolds was designed and prepared to catalyse a serial of asymmetric Michael addition of 1,3-dicarbonyl compounds to α,β-unsaturated carbonyl compounds in high yields (up to 99 %) and good to excellent enantiomeric excesses (up to 99% ee). The comparative experiments indicated that the cooperative effect between calixarenes cavitives and chiral catalytic centers on this calix[4]squaramide catalyst could promote these reactions. Moreover, this strategy also provides valuable and easy access to chiral chromene, naphthoquinone and acetylacetone derivatives, which are important skeletons in biological and pharmaceutical compounds.

Photo-induced self-healing materials, which can be controlled remotely, instantly and precisely, are attracting increasing attention in various fields. However, it still remains challenging to modulate the self-healing materials with integrated functionalities possessing multiple-wavelength photo-responsiveness. Herein, we report a strategy of building a photo-responsive self-healing system capable of performing ultraviolet (UV) and near-infrared (NIR) two-wavelength induced double-repair. The strategy is based on azobenzene-functionalized multiwalled carbon nanotubes (MWCNTs) via a two-step method. Oxidized MWCNTs were first reacted subsequently with thionyl chloride, glycol, and 2-bromoisobutyryl bromide to yield MWCNT-Br macroinitiators. Then atom transfer radical polymerization (ATRP) of azobenzene monomer, 6-(4-butyl-4′-oxyazobenzene) hexyl methacrylate (Azo), was directly initiated by MWCNT-Br, affording MWCNT-PAzo nanocomposites. The MWCNT-PAzo system can undergo photothermal- and photochemical-induced solid-liquid phase transition to manipulate the self-healing behavior while MWCNTs act as photo-absorbers/heat sources and azobenzene moieties serve on glass transition temperatures (Tg) switchers, in response to NIR and UV light stimuli, respectively. To our best of knowledge, this is the first-time that MWCNT-PAzo nanocomposites possess two-wavelength photo-responsiveness and exhibit excellent self-healing performance through the irradiation of two-wavelength bands (365 and 808 nm) of UV/NIR light.

Purpose/Aim: Pulmonary fibrosis (PF) is characterized by the progressive and ultimately fatal accumulation of fibroblasts and extracellular matrix in the lung that distorts its architecture and compromises its function.Objective: The present study investigated the potential protective effects of schisandrin B (Sch B) on the Wingless/Integrase-1 (Wnt) signaling pathway in attenuating inflammation and oxidative stress in ICR mice.Methods: Sixty healthy ICR mice were randomly divided into the following groups: control group, bleomycin (BLM) group, Sch B low dose (Sch B-L) group, Sch B medium dose (Sch B-M) group, Sch B high dose (Sch B-H) group, and dexamethasone (DXM) group. The expression of transforming growth factor (TGF)-β1 was examined by ELISA. In addition, the levels of superoxide dismutase (SOD), hydroxyproline (HYP), and the total antioxidant capacity (T-AOC) were determined. The protein and mRNA levels of matrix metalloproteinase 7 (MMP7) and β-catenin in mice were analyzed by western blot and quantitative real -quantitative time PCR (qRT-PCR), respectively.Results: Lung tissues from the BLM group exhibited significantly more inflammatory changes and a significantly greater number of collagen fibers than lung tissues from the control group. In addition, the lung tissues from these BLM-treated mice exhibited slightly increased MMP7 and β-catenin protein expression. Lung tissues from the Sch B-H group exhibited fewer inflammatory changes and fewer collagen fibers than lung tissues from the BLM group. Furthermore, the lung tissues from the Sch B-H mice exhibited decreased HYP and TGF-β1 levels, but increased SOD and T-AOC levels.Conclusions: The present study provided evidence that Sch B may be a potential therapeutic agent for the treatment of PF.

Allosteric effects are common in biology, but have not been fully explored in the control of supramolecular polymerization. Herein, ditopic UPy derivatives with acyclic crown ether-like spacers were designed and synthesized, which can undergo supramolecular polymerization through quadruple hydrogen bonding. Upon the addition of K+, drastic molecular conformational change to the U-shape is induced by metal-coordination, reconfiguring remote UPy sites towards the formation of discrete cyclic dimers. Interestingly, the supramolecular polymerization can be restored by simply removing K+ by water-extraction.

Carbon dioxide is an ideal raw material for the synthesis of complex organic compounds because of its rich, non-toxic, and good physical properties. It is of great significance to transform CO2 into valuable fine chemicals and develop a green sustainable cycle of carbon surplus. Based on hydrosilane as a reducing agent, this work summarizes the recent applications of reductive amidation of CO2 using different catalysts such as organocatalysts, ionic liquids (ILs), salts, transition metal complexes, and solvents. The main factors affecting the reductive amidation of CO2 and the possible reaction mechanism are discussed. Moreover, the future orientation and catalytic systems of the formylation of amines with CO2 and hydrosilane are prospected.

L-theanine is a nonprotein amino acid found in tea leaves and has been widely used as a safe food additive in beverages or foods because of its varied bioactivities. The aim of this study was to reveal the in vitro gastrointestinal protective effects of L-theanine in DSS-induced intestinal porcine enterocyte (IPEC-J2) cell models using molecular and metabolic methods. Results showed that 2.5% dextran sulfate sodium (DSS) treatment inhibited the cell proliferation of IPEC-J2 and blocked the normal operation of the cell cycle, while L-theanine pretreatment significantly preserved these trends to exert protective effects. L-theanine pre-treatment also up-regulated the EGF, CDC2, FGF2, Rb genes and down-regulated p53, p21 proliferation-related mRNA expression in DSS-treated cells, in accompany with p53 signaling pathway inhibition. Meanwhile, metabolomics analysis revealed that L-theanine and DSS treated IPEC-J2 cells have different metabolomic profiles, with significant changes in the key metabolites involved in pyrimidine metabolism and amino acid metabolism, which play an important role in nucleotide metabolism. In summary, L-theanine has a beneficial protection in DSS-induced IPEC-J2 cells via promoting proliferation and regulating metabolism disorders.

In this paper, we study inventory management for the one warehouse multi-retailer (OWMR) system with considering carbon emissions, in which we determine the reorder intervals for the warehouse and the retailers while minimizing the inventory ordering and holding cost and the carbon emission cost. We consider the carbon emissions from the holding and replenishing inventory activities in the OWMR system, and calculate the carbon emissions based on the frequency of the inventory replenishment at the warehouse and the retailers. We focus on stationary and integer-ratio policies, and formulate the problem as an optimization model with a convex objective function and a set of integer-ratio constraints. We relax the integer-ratio constraints, and introduce an algorithm to solve the corresponding relaxed problem to optimality in O ( n log n ) times, where n represents the number of retailers. Based on the optimal solution of the relaxed problem, we build an integer-ratio policy, i.e., power-of-two (POT) policy, with 94% optimality for the primal problem. The computational results show that with considering the carbon emission cost, the reorder intervals of the warehouse and the retailers both increase, and that the integrated model proposed in this paper has more superiorities in terms of reducing the system-wide cost and the carbon emissions.

Here we report our research on biomimetic folding architectures self-assembled hierarchically from well-designed UPy-based monomers with low molecular weight (MW < 400 Da). These monomers are first dimerized via quadruple hydrogen bonding and then form folded dimers with the assistance of π–π interactions. More interestingly, the folded dimer further formed one-dimensional supramolecular stacks through additional weak π–π interactions in the solid state. Similar to DNA, these well-defined structures are stabilized by the concerted hydrogen bonding and π–π interaction in a synergistic manner, which would provide inspiration for constructing biomimetic self-folding materials.

The control of supramolecular polymerization is of high fundamental significance for understanding self-assembly processes at the nanoscale. It also remarkably affects the design and improves the efficiency of dynamic polymer materials. To this end, we have developed an effective strategy which employs a type of non-covalent interaction to orthogonally regulate the supramolecular polymerization driven by another non-covalent interaction. Specifically, we herein report the quadruple hydrogen bond-driven supramolecular polymerization controlled by the assistance of the π–π interaction. A series of aromatic group bridged ditopic ureidopyrimidinone (UPy) derivatives (M1, M2, and M3) were designed and successfully synthesized. These molecules could self-assemble into cyclic monomers or linear supramolecular polymers under different conditions via quadruple hydrogen bonding. By additionally introducing a π–π interaction into the cyclic monomers, which exists between the aromatic group and the dimerized UPy motifs, a ring-opening supramolecular polymerization process based on ring-chain equilibrium can be preliminarily controlled due to the adjustable strength of the π–π interaction. These findings could offer new perspectives into orthogonal self-assembly and provide model systems for the studies of fundamental supramolecular polymer physics.

The relationship between molecular structure and macroscopic characteristics is a fundamental issue for materials design. Some minor changes in molecular structure may have a great impact on the molecular self-assembly process. Therefore, it is of interest to design new isomeric building blocks for supramolecular self-assembly, offering inspiration for the development of smart materials by supramolecular engineering. In this study, two dioxynaphthalene (DNP) group bridged bifunctional ureidopyrimidinone (UPy) monomers (DNP1 and DNP2) were synthesized. The chemical structures of the two isomers are very similar and the only difference is that DNP1 is 2,6-substituted and DNP2 is 1,5-substituted on the DNP motif. Interestingly, these two isomers exhibit completely different supramolecular self-assembly behaviors. Highly viscous supramolecular polymers were obtained in a concentrated solution of DNP1, while crystals based on highly stable cyclic monomers were precipitated from a concentrated solution of DNP2. Since DNP is an electron rich group, the host–guest behaviors of DNP1 and DNP2 with a blue-box were further studied, which also showed different ring-threading capabilities.

Nonnutritive sweeteners (NNSs) are sugar substitutes widely used to reduce the negative health effects of excessive sugar consumption. Dental caries, one of the most prevalent chronic diseases globally, results from a pathogenic biofilm with microecological imbalance and frequent exposure to sugars. Some research has shown that certain NNSs possess less cariogenic potential than sucrose, indicating their putative effect on oral microbiome. To uncover the alterations of acidogenic pathogens and alkali-generating commensals, as well as the biofilm cariogenic potential under the influence of NNSs, we selected four common NNSs (acesulfame-K, aspartame, saccharin, and sucralose) and established single-, dual-, and multispecies in vitro culture model to assess their effects on Streptococcus mutans (S. mutans) and/or Streptococcus sanguinis (S. sanguinis) compared to sucrose with the same sweetness. The results showed that NNSs significantly suppressed the planktonic growth, acid production, and biofilm formation of S. mutans or S. sanguinis compared with sucrose in single-species cultures. Additionally, decreased S. mutans/S. sanguinis ratio, less EPS generation, and higher pH value were observed in dual-species and saliva-derived multispecies biofilms with supplementary NNSs. Collectively, this study demonstrates that NNSs inhibit the cariogenic potential of biofilms by maintaining microbial equilibrium, thus having a promising prospect as anticaries agents.

With the aid of CTAB amphiphile, water-phase artificial light-harvesting systems were fabricated as nanoparticles by the self-assembly of two low-molecular-weight organic molecules: a UPy-functionalized TPE derivative 1 with both supramolecular polymerization and AIE capabilities as a donor and a fluorescent chromophore NiR as an acceptor. Owing to the flexibility of supramolecular self-assembly, tunable emissions including white-light emission could be easily realized with high energy transfer efficiency and the antenna effect.

S-glutathionylation is an important post-translational modification (PTM) process that targets protein cysteine thiols by the addition of glutathione (GSH). This modification can prevent proteolysis caused by the excessive oxidation of protein cysteine residues under oxidative or nitrosative stress conditions. Recent studies have suggested that protein S-glutathionylation plays an essential role in the control of cell-signaling pathways by affecting the protein function in bacteria and even humans. In this study, we investigated the effects of S-glutathionylation on physiological regulation within Streptococcus mutans, the primary etiological agent of human dental caries. To determine the S-glutathionylated proteins in bacteria, the Cys reactive isobaric reagent iodoacetyl Tandem Mass Tag (iodoTMT) was used to label the S-glutathionylated Cys site, and an anti-TMT antibody-conjugated resin was used to enrich the modified peptides. Proteome profiling identified a total of 357 glutathionylated cysteine residues on 239 proteins. Functional enrichment analysis indicated that these S-glutathionylated proteins were involved in diverse important biological processes, such as pyruvate metabolism and glycolysis. Furthermore, we studied a thioredoxin-like protein (Tlp) to explore the effect of S-glutathionylation on interspecies competition between oral streptococcal biofilms. Through site mutagenesis, it was proved that glutathionylation on Cys41 residue of Tlp is crucial to protect S. mutans from oxidative stress and compete with S. sanguinis and S. gordonii. An addition rat caries model showed that the loss of S-glutathionylation attenuated the cariogenicity of S. mutans. Taken together, our study provides an insight into the S-glutathionylation of bacterial proteins and the regulation of oxidative stress resistance and interspecies competition., Author summary S-glutathionylation is involved in many physiological processes such as antioxidation, detoxification and cell proliferation. However, the proteomics research on S-glutathionylation has never been performed in gram-positive bacteria. The identification of and functional studies on glutathione reductase, glutathione synthesis dual-functional enzyme and glutathione-S-transferase in Streptococcus mutans, the main causative agent of dental caries, inspired the existence of complete S-glutathionylation system in this type of bacteria. It may impact various crucial physiological processes by regulating the function of modified proteins. Here, we explored the entire S-glutathionylation proteome through high-specific labeling and high-sensitivity mass spectrometry technologies. The results showed that about 11.7% of the total S. mutans proteins were S-glutathionylated, which indicated that S-glutathionylation plays a fundamental role in the regulation of cellular processes. Through functional analysis and domain prediction, we next uncovered a potential thioredoxin that contains two modified cysteines on its key active motif; S-glutathionylation of the sites affected the oxidative resistance, competition and cariogenecity of S. mutans. We anticipate that S-glutathionylation proteome studies could be performed on more refractory infectious diseases, revealing more mechanisms of pathogen infection and providing new methods to treat infectious diseases.

A number of upper rim-functionalized calix[4]thiourea cyclohexanediamine derivatives have been designed, synthesized and used as catalysts for enantioselective Michael addition reactions between nitroolefins and acetylacetone. The optimal catalyst 2 with a mono-thiourea group exhibited good performance in the presence of water/toluene (v/v = 1:2). Under the optimal reaction conditions, high yields of up to 99% and moderate to good enantioselectivities up to 94% ee were achieved. Detailed experiments clearly showed that the upper rim-functionalized hydrophobic calixarene scaffold played an important role in cooperation with the catalytic center to the good reactivities and enantioselectivities.

Coal gasification wastewater (CGW) possess a high phenolics content, how to remove phenols is the crux of the environmental problems. In this work, we report the design and synthesis of a several highly graphitized ordered mesoporous carbons (OMCs) by carbonization of precursors from phenol and formalin. The obtained porous OMCs have uniform structures with the pore size, order degree, and surface areas being controllable by varying the synthesis conditions. In depth study of the prepared materials reveals that the OMCs carbonized at 923.15 K exhibit ordered 2D hexagonal mesoporous structures with high degree of graphitization, high surface area (590.6 m2·g−1), appropriate pore size (mean diameter about 10 nm) and large mesoporous pore volume (0.512 cm3·g−1). The prepared OMCs are applied as adsorbent for treatment of the CGW collected directly from the biochemical effluent of coal chemical enterprise in Inner Mongolia Autonomous region, China. The OMCs show excellent adsorption properties for phenol effluent with the removal efficiency of phenols being up to 92.3%. The adsorption experiment data demonstrates that the adsorption is a multi-molecular layer adsorption process, during which the physical adsorption takes place. In addition, the study of adsorption thermodynamics indicates that the adsorption process is spontaneous and endothermic. The adsorption of samples on phenol from CGW has reached an ideal level.

A novel oxo-spirocyclic structure bridged ditopic Schiff base fluorescent probe L has been successfully synthesized and characterized. Interestingly, probe L exhibits a specific turn-on response to zinc(II) ion in fluorescence with a high selectivity and sensitivity. Further study show that probe L could be applied in imaging of live cells for sensing zinc(II) ion. By contrast, those compounds (L1, L2, and L3) with very similar structure to L lack this properties. The fluorescence intensity of L increases with Zn2+, which is less affected by other metal ions. The binding property of L with Zn2+ was studied by a combination of technologies, such as Job's plot, 1H NMR, ESI-MS, and DFT calculations. Moreover, we have successfully applied the probe L to detect Zn2+ in cancer cell. We are anticipating that this new oxo-spirocyclic structure bridged ditopic Schiff base may provide a new idea for the design of fluorescent probe.

A milder, more regioselective and practical approach to C3 or O-alkylation reaction of 4-hydroxycoumarins has been established. Both 2H-[3,2-c] furocoumarins and 4-hydroxycoumarin vinyl ether derivatives could be efficiently prepared by alkylating 4-hydroxycoumarins with electron-deficient allenoates catalyzed by PPh3 and DBU, respectively. The reaction outcomes can be controlled by changing the catalysts, starting with the same reaction substrates. Possible reaction mechanisms have also been proposed

A first optical resolution of 6,12-diphenyldibenzo[b,f][1,5]diazocine with stable boat conformation was achieved by chiral supercritical fluid chromatography (SFC). The absolute configurations of enantiomers were first assigned and determined by X-ray crystal structure based on CIP-rules. The high optical rotation and circular dichroism spectrum were well explained by electronic helix theory. Owing to the high stabilization of boat conformation, the chiral configuration could be maintained at very high temperature, more than 200 °C, which was proved by Density Functional Theory calculations.

A series of upper rim-functionalized calix[4]arene-based l -Proline derivatives have been synthesized and employed for the enantioselective aldol reactions between cyclic ketones and aromatic aldehydes in the presence of water. Good to excellent yields (up to 96%), enantioselectivities (up to 99% ee ), as well as diastereoselectivities (up to 99:1 dr ) were obtained under the optimal reaction conditions. Detailed experiments clearly showed that the hydrophobic calixarene platform not only contributed to the good reactivities and enantioselectivities, but also exhibited size-selective catalysis function. Moreover, the organocatalyst can be readily recovered and reused for several runs without significant loss in its enantioselectivity.

Purpose/Aim: More and more evidences suggest that airway remodeling of fibrotic lung diseases may be associated with epithelial-mesenchymal transition (EMT) of human A549 cells induced by transforming growth factor (TGF)-β1. Schisandrin B (Sch B) is the highest content of dibenzocyclooctadiene lignans in Schisandra chinensis. In this study, we assessed the inhibitory influences of Sch B on TGF-β1-stimulated EMT in human A549 cells. Materials and Methods: The influences of Sch B on cell viability, invasion and metastasis in TGF-β1-induced human A549 cells were detected by MTT, wound healing and transwell invasion assays. The expression levels of α-SMA, E-cadherin, ZEB1 and Twist1 were examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The enrichment of H3K4me3 and H3K9me3 at the ZEB1 promoter was determined by ChIP analysis. Results: Experimental results showed that Sch B increased the expression of the epithelial phenotype marker E-cadherin and inhibited the expression of the mesenchymal phenotype marker α-SMA during EMT induced by TGF-β1. The enhancement in invasion and migration of TGF-β1-induced A549 cells was inhibited by Sch B. Sch B also repressed the expression of ZEB1 transcription factor in EMT, by increasing the enrichment of H3K9me3 at the ZEB1 promoter to repress its transcription while the expression of the Twist1 transcription factor was unaffected. Conclusions: Our data suggest that Sch B can prevent TGF-β1-stimulated EMT in A549 cells through epigenetic silencing of ZEB1, which may be clinically related to the efficient treatment of EMT-associated fibrotic diseases.

Herein an aqueous-phase artificial light-harvesting platform has been constructed based on the self-assembly of three small organic molecules: a rigid acetal-based spirocyclic skeleton bridged tetraphenylethylene dimer as donor, a hydrophobic dye molecule Nile Red as acceptor, and the surfactant cetyltrimethyl ammonium bromide as amphiphile to enwrap the donor and acceptor and disperse them in water. Due to the rigid skeleton of the tetraphenylethylene dimer that can well accommodate and distribute Nile Red inside the self-assembled nanospheres, the system shows ultrahigh light-harvesting antenna effects. Moreover, by simply tuning the donor/acceptor molar ratio, tunable emission including a bright white-light emission could be realized.

We unify the diffusion and seepage process for nonlinear gas transport in multiscale porous media via a proposed new general transport equation. A coherent theoretical derivation indicates the wall-molecule and molecule-molecule collisions drive the Knudsen and collective diffusive fluxes, and constitute the system pressure across the porous media. A new terminology, nominal diffusion coefficient can summarize Knudsen and collective diffusion coefficients. Physical and numerical experiments show the support of the new formulation and provide approaches to obtain the diffusion coefficient and permeability simultaneously. This work has important implication for natural gas extraction and greenhouse gases sequestration in geological formations.

A simple and nontoxic fluorescent chemosensor of di-O-methyl curcumin has been prepared from curcumin. The sensor exhibited selective and sensitive fluorescent responses toward Al3+ over a wide range of metal ions, such as Mn2+, Ce3+, Pt2+, Sn4+, Hg+, Sb3+, K+, Ca2+, Mg2+, Ba2+, Cu2+, Ni2+, Na+, NH4+, Ag+, Pb2+, Zn2+, Fe2+, Fe3+, Hg2+ and Cr3+ in ethanol/water. The free ligand showed quite weak fluorescence emission due to the isomerization of CO double bond in the excited state, however, after addition of Al3+, fluorescence emission results in a prominent fluorescence enhancement.

There is no effective method for treating pulmonary fibrosis (PF) until now. This study investigated the anti-fibrotic effect of schisantherin A (SCA) extracted from Schisandra chinensis and its potential molecular mechanism in PF. A bleomycin-induced PF mouse model in vivo and transforming growth factor (TGF)-β1-induced A549 epithelial-mesenchymal transition (EMT) cell model in vitro were used for assessing the anti-fibrotic effect of SCA. Histopathological examination was conducted after hematoxylin and eosin and Masson staining. The level of TGF-β1 was tested by ELISA. The expression levels of α-smooth muscle actin, E-cadherin, and inflammatory cytokines (COX2, IL-1β, IL-6, and TNF-α) were determined by quantitative reverse transcription polymerase chain reaction and Western blot. The expression of extracellular signal-regulated kinase (ERK) was tested in lung tissues and cells by Western blot. The in vivo experiments revealed that SCA treatment markedly improved body weight and pulmonary index and reformed the destruction of the lung tissue structure. We observed that SCA inhibited the process of TGF-β1-induced EMT in the in vitro experiments. Inflammatory cytokines were reduced greatly in lung tissues and cells by SCA. Our study also indicated that SCA decreased phosphorylated ERK. It was concluded that SCA can attenuate PF by regulating the ERK signaling pathway, which suggests that SCA may be used as a potential therapeutic drug for PF.

Paraquat (PQ) induces acute lung injury (ALI) and immunotoxicity. Apigenin exerts anti-oxidant and anti-inflammatory properties. The purpose of this study was to investigate the possible protective effects of apigenin on PQ-induced ALI and immunotoxicity in mice. Female C57BL/6 mice received a single injection of PQ (50 mg/kg). Apigenin was given for 7 consecutive days starting 5 days before PQ exposure. The toxicity markers were evaluated in terms of weight loss, lung histopathology, oxidative stress, inflammation, and T cell functions after PQ exposure. Poisoned mice exhibited severe lung tissue lesions, inflammatory cell infiltration and the release of pro-inflammatory cytokines IL-6 and TNF-α. PQ administration increased the lung wet/dry ratios and lipid peroxidation by the increase of MDA levels and decreased anti-oxidase activity including SOD, GSH-PX, and CAT. While such effect on lung was reversed by apigenin. Importantly, PQ-induced immunotoxicity was also observed in a decrease of spleen weight, inhibition of T cell proliferation and T-cell secreting IL-2 from splenocytes. Further mechanism analysis found that PQ administration could decrease total splenocytes, CD4+ and CD8+ T cells, SOD, GSH-PX, and CAT activity, and increased the levels of MDA and the concentrations of pro-inflammatory cytokines IL-6 and TNF-α compared to control mice. However, apigenin treatment reversed PQ-induced immunotoxicity. In summary, all results suggest that apigenin has beneficial effects on PQ-induced ALI and immunotoxicity possibly, and it could be related, at least in part, to its ability in modulating inflammation and oxidative stress, although in-depth studies might be needed to fully understand the mechanism of action.

Uridine diphosphate-glucuronosyltransferases (UGTs) are the most important phase II enzymes in human drug metabolism. Using permeabilized recombinant fission yeast cells (enzyme bags), we demonstrate that UGT1A5 can catalyze an N-glucuronidation reaction. We characterized two new polymorphic UGT1A5 variants: a common ninefold mutant (UGT1A5*8) with double-fold activity and a much rarer sixfold mutant (UGT1A5*9), which has the same activity as the wild-type. Molecular modeling studies indicate that the minor effects of all mutations, except for Gly259Arg, are due to their distance to the substrate binding site. Extensive molecular dynamics simulations revealed that the Gly259Arg mutation stabilizes helix Q through a newly formed hydrogen bonding network, which places the cofactor in a much more favorable geometry in UGT1A5*8 as compared to the wild-type.

A novel calix[4]arene based chemosensor L which contains coumarin and thiourea group has been synthesized and characterized. Interestingly, probe L exhibits both fluorescent and colorimetric response to fluoride anion with high selectivity and sensitivity. The addition of F- to a solution of probe L resulted in obvious naked-eye color change from colorless to orange under daylight and prominent fluorescence quenching. Further studies showed that the recognition process was less affected by other anions. The binding property of L with F- was studied by a combination of combination of various spectroscopic techniques, such as absorption spectra, fluorescence titration, Job's plot and 1H NMR titration. We are anticipating that this architecture with functional group attached to upper rim of calix[4]arene platform may provide a new approach for the development of F- chemosensor.

With the increasing attention being paid to the development of unconventional reservoirs, such as shale gas or tight gas reservoirs with nanoscale pores, over the last few years, there is a great demand to develop a coherent theoretical framework that explains the transport mechanisms that take place in a nanoporous medium. In this paper, a complete modelling workflow that spans the mesoscale to the macroscale, including the lattice Boltzmann model (LBM) and Navier–Stokes equations, is introduced to reflect these transport characteristics. Gas flow for different pore diameters and Knudsen numbers is simulated by LBM. Comparison between physical experimental measurements and the LBM simulation results shows that the general transport equation is most appropriate for describing gas flow in nanoporous media and that the values of the diffusion coefficient and intrinsic permeability can be obtained simultaneously using this equation. Intrinsic permeability decreases faster than the diffusion coefficient with the decreasing average pore diameters in nanoporous media. The general transport equation has been verified to reflect the mechanisms of flow and diffusion in nanoporous media, and it also provides a theoretical basis to assess the results attained from numerical simulations.

The development of bimetallic iron oxide-silver magnetic nanoparticles (Fe2O3–Ag MNPs) catalytic system provides an efficient heterogeneous synthetic pathway to allylic amines and 1,2-dihydroquinolines involving the direct inter/intramolecular nucleophilic substitution of π-activated alcohols with electron-deficient amines. The major advantages of the present method are wide substrate scope, simple product separation, low catalyst loading, and magnetically recyclable catalyst.

A facile and efficient synthesis of isothiocyanates from amines is described. This method involves the reaction of amines with phenyl chlorothionoformate in the presence of solid sodium hydroxide by either a one-pot process or a two-step approach. The one-pot process is useful for preparing alkyl and electron-rich aryl isothiocyanates, whereas the two-step approach is more versatile, working very well not only for alkyl and electron-rich aryl isothiocyanates, but also for highly electron-deficient aryl and heterocyclic isothiocyanates.

The first Lewis acid-catalyzed intramolecular interrupted Nazarov cyclization of 1,4-pentadien-3-ols is described. Using FeBr3 as the catalyst, a series of new substituted cyclopenta[b]indoles was prepared—through a sequence of Nazarov cyclization, nucleophilic amination, and isomerization—with good yields and high diastereo- and regioselectivities. A similar catalytic process was also developed for the synthesis of structurally interesting spiro[indene-1,4′-quinoline]s.

The first Lewis acid-catalyzed intramolecular interrupted Nazarov cyclization of 1,4-pentadien-3-ols is described. Using FeBr3 as the catalyst, a series of new substituted cyclopenta[b]indoles was prepared—through a sequence of Nazarov cyclization, nucleophilic amination, and isomerization—with good yields and high diastereo- and regioselectivities. A similar catalytic process was also developed for the synthesis of structurally interesting spiro[indene-1,4′-quinoline]s.

This study examined the role of protein kinase C (PKC) isozymes in methamphetamine (MA)-induced dopaminergic toxicity. Multiple-dose administration of MA did not significantly alter PKCα, PKCβI, PKCβII, or PKCζ expression in the striatum, but did significantly increase PKCδ expression. Gö6976 (a co-inhibitor of PKCα and -β), hispidin (PKCβ inhibitor), and PKCζ pseudosubstrate inhibitor (PKCζ inhibitor) did not significantly alter MA-induced behavioral impairments. However, rottlerin (PKCδ inhibitor) significantly attenuated behavioral impairments in a dose-dependent manner. In addition, MA-induced behavioral impairments were not apparent in PKCδ knockout (–/–) mice. MA-induced oxidative stress (i.e., lipid peroxidation and protein oxidation) was significantly attenuated in rottlerin-treated mice and was not apparent in PKCδ (–/–) mice. Consistent with this, MA-induced apoptosis (i.e., terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive apoptotic cells) was significantly attenuated in rottlerin-treated mice. Furthermore, MA-induced increases in the dopamine (DA) turnover rate and decreases in tyrosine hydroxylase (TH) activity and the expression of TH, dopamine transporter (DAT), and vesicular monoamine transporter 2 (VMAT2) were not significantly observed in rottlerin-treated or PKCδ (–/–) mice. Our results suggest that PKCδ gene expression is a key mediator of oxidative stress and dopaminergic damage induced by MA. Thus, inhibition of PKCδ may be a useful target for protection against MA-induced neurotoxicity.

A series of novel supramolecular organocatalysts of hydroxyprolinamide based on the upper rim of calix[4]arene scaffold have been developed to catalyze enantioselective multi-component Biginelli reaction. Under the optimal conditions, the reactions occurred with moderate-to-excellent enantioselectivities (up to 98% ee). A plausible transition state constructed by the supramolecular interaction of hydrogen bond and cation-π between catalysts and substrates has been proposed.

Bridging of calix[4]arene derivatives with optically active subunits derived from chiral l/d-amino alcohols has resulted in two novel calix[4]azacrowns enantiomers S-C51H64NO7·CH3OH·H2O (S-1) and R-C51H64NO7·CH3OH·H2O (R-1), which were crystallized separately. Single crystal X-ray diffraction studies revealed that they each encapsulate a methanol molecule by weak interactions and that they form supramolecular enantiomeric helical arrangements along the crystallographic axis, which are constructed via C–H···O hydrogen bonds involving bridging water molecules. A similar helical arrangement was also found in the crystal structure of a previously reported calix[4]azacrown compound S-C108H146N2O16 (S-2).