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The mechanisms of N‐heterocyclic carbene (NHC)‐catalyzed dearomatization reaction of alkyl pyridinium have been intensively studied using the density functional theory (DFT) method. The chemoselectivity and stereoselectivity were both analyzed based on the established mechanisms. The computational results showed that the chemoselective C4‐addition occurred before the C2‐addition, which is mainly because the C4 atom was more reactive according to the local reactivity analysis. The stereoselectivity was also investigated, and the C−C bond formation step was identified as the stereoselectivity‐determining step. The C−H⋅⋅⋅F and O−H⋅⋅⋅N interactions are identified as the main factors that govern the stereoselectivity by NCI analysis, and the preferred product was the RS‐configuration. This theoretical investigation would provide a case for understanding and predicting the selectivity of the organocatalytic dearomatization reactions of alkyl pyridinium. [ABSTRACT FROM AUTHOR]

The base‐controlled mechanisms for N‐heterocyclic carbene (NHC)‐catalyzed divergent [3+3] and [3+2] annulation reactions were examined by using the DFT method. The reaction initiates with the complexation of NHC and enal to give the Breslow intermediate, which diverges afterward. Then, the azomethine imine can either react with the Breslow intermediate to give the six‐membered ring product or the β‐carbon protonation occurs for forming the enolate intermediate controlled by different bases. The formed enolate intermediate reacts with azomethine imine to afford the five‐membered ring product. The calculated results show that only the base K2CO3 can facilitate the structural transformation between homoenolate and enolate to switch the chemoselectivity; therefore, the [3+3] annulation happens preferentially in the presence of base DBU while the other situation occurs with K2CO3 as base. The NCI analysis results reveal that the stereoselectivity is predominately determined by the π⋅⋅⋅π, C−H⋅⋅⋅O, and C−H⋅⋅⋅N interactions. The obtained mechanistic insights should provide valuable clues for the rational design of these kinds of divergent reactions. Taking control: The origin of base‐controlled divergent chemoselectivity has been predicted by using the DFT method. [ABSTRACT FROM AUTHOR]

Abstract: To enhance the Seebeck coefficient and reduce the thermal conductivity while maintaining a satisfied electrical conductivity, a disordered structure was introduced into the La0.3Ce0.37Fe3CoSb12 crystalline by adding a low-melting-point lead telluride (PbTe). The results suggest that the disordered structure created by the melted PbTe at 870K can be partly preserved into the La0.3Ce0.37Fe3CoSb12 materials at room temperature. With the existence of the disordered structure the Seebeck coefficient at 773K is increased from 143μVK−1 to 265μVK−1, while the thermal conductivity is reduced from 2.12Wm−1 K−1 to 1.60Wm−1 K−1, nevertheless the electrical conductivity is dropped from 78,000Ω−1 m−1 to 23,500Ω−1 m−1. A figure of merit of 0.95 at 773K is observed for the material containing 40% PbTe. [Copyright &y& Elsevier]

Three new lanthanide coordination polymers, [Ln(Ad)3/2(Phen)]n·2nH2O (Ln = Eu, 1; Pr, 2; Ad = adipate; Phen = 1,10-phenanthroline) and [Yb(Ad)3/2(Phen)]n·nH2O 3, were prepared by hydrothermal reactions. The structures of 1, 2 and 3 are reported. In compound 1, Eu(III) ions are bridged by adipate ligands in two modes into 2-D polymeric layers. Adjacent layers are assembled by hydrogen bonding and π-π stacking between 1,10-phenanthrolines into a 3-D supramolecular structure. Compound 2 is isostructural with 1. In compound 3, the Yb(III) ions are connected by adipate ligands in three modes into a 3-D network. [ABSTRACT FROM AUTHOR]

7-Hydroxyflavone was phosphorylated by a modified Atherton-Todd reaction and the resulting structure determined by NMR, ESI-MS/MS and elemental analysis. The electrospray ionization results showed that phosphorylated flavonoids can form non-covalent complexes with many proteins such as lysozyme, cytochrome c , bovine insulin and myoglobin, while non-covalent complexes were not detected with a mixed solution of 7-hydroxyflavone and proteins. It is deduced that phosphorylated flavonoids possess relatively strong affinities for proteins and form non-covalent complexes with proteins more easily than the unphosphorylated compounds. [ABSTRACT FROM AUTHOR]

Lycium ruthenicum Murray possesses significant applications in both food and medicine, including antioxidative, anti-tumor, anti-fatigue, anti-inflammatory, and various other effects. Consequently, there has been a surge in research endeavors dedicated to exploring its potential benefits, necessitating the organization and synthesis of these findings. This article systematically reviews the extraction and content determination methods of active substances such as polysaccharides, anthocyanins, flavonoids, and polyphenols in LRM in the past five years, as well as some active ingredient composition determination methods, biological activities, and product development. This review is divided into three main parts: extraction and determination methods, their bioactivity, and product development. Building upon prior research, we also delve into the economic and medicinal value of Lycium ruthenicum Murray, thereby contributing significantly to its further exploration and development. It is anticipated that this comprehensive review will serve as a valuable resource for advancing research on Lycium ruthenicum Murray. [ABSTRACT FROM AUTHOR]

In present study, a novel glutathione functionalized MoS 2 quantum dots (GSH-MoS 2 QDs) was synthesized from sodium molybdate dehydrate and glutathione by using a one-pot hydrothermal method. After they were characterized, the influence of GSH-MoS 2 QDs on amyloid aggregation of bovine serum albumin (BSA) was investigated by various analytical methods including thioflavin T fluorescence assay, circular dichroism and transmission electron microscope. Moreover, the effect of GSH-MoS 2 QDs on cytotoxicity induced by BSA amyloid fibrils and cell penetration were evaluated by MTT assay and confocal fluorescence imaging, respectively. The results indicated that the GSH-MoS 2 QDs not only had good water solubility, excellent biocompatibility and low cytotoxicity, but also could obviously inhibit the aggregation of BSA and depolymerize the formed BSA aggregates. The data obtained from this work demonstrated that the GSH-MoS 2 QDs is expected to become a candidate drug for the treatment of amyloid-related diseases. • A novel GSH-MoS 2 QDs was synthesized by one-pot hydrothermal approach. • The as-prepared QDs can inhibit BSA aggregation and depolymerize BSA fibrils. • The QDs exhibits good biocompatibility, low cytotoxicity and cell permeability. [ABSTRACT FROM AUTHOR]

• Three 1D/2D Cd(II) coordination complexes can be constructed from semirigid bis(dimethylbenzimidazole) ligand and different carboxylates. • Complex 3 shows highly sensing for p-Nitrophenol, erythromycin and 2,6-Dichloro-4-nitroaniline with fluorescence quenching/enhancement. • We investigate the mechanism of the detection by theoretical calculation. Three Cd(II) coordination complexes, formulated as [Cd(dbim)(p -phda)] n (1), [Cd(dbim) 1.5 (suc)] n (2), [Cd(dbim) 0.5 (m -bdc)(2H 2 O)] n (3) (dbim = 1-(4-((2,5-dimethyl-3a H -benzo[ d ]imidazol-1(7a H)-yl)methyl)benzyl)-3a,7a-dihydro-2,5-dimethyl-1 H -benzo[ d ]imidazole, p -H 2 phda = p -phenylenediacetic acid, H 2 suc = succinic acid, m -H 2 bdc = 1,3-benzenedicarboxylic acid), have been obtained by hydrothermal reactions. Complex 1 features a 4-connected 2D topological net with a point symbol of 44·62. Complex 2 possesses a 3-connected 2D layer with a point symbol of 63. Complex 3 presents a chain structure ornamented with uncoordinated Lewis basic O donor. Complex 3 shows highly sensing for p -Nitrophenol, Erythromycin and 2,6-Dichloro-4-nitroaniline with fluorescence quenching/enhancement, by energy transfer process. The binding constants were calculated as 2.9 × 104 mol−1 for p -Nitrophenol, 5.3 × 103 mol−1 for Erythromycin and 7.2 × 103 mol−1 for 2,6-Dichloro-4-nitroaniline, respectively. The study indicates that Complex 3 can be as a rare sensory material for efficiently detecting p -Nitrophenol, Erythromycin and 2,6-Dichloro-4-nitroaniline. Three 1D/2D Cd(II) coordination complexes can be constructed from semirigid bis(dimethylbenzimidazole) ligand and different carboxylates. Complex 3 shows highly sensing for p-Nitrophenol, Erythromycin and 2,6-Dichloro-4-nitroaniline with fluorescence quenching/enhancement. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, rose bengal‐derived carbon quantum dots (RB‐CQDs) was synthesized by a one‐step solvothermal method using rose bengal and 1,2‐phenylenediamine as precursors in ethanol at 180 °C for 10 h and purified by silica gel chromatography. The as‐synthesized RB‐CQDs disperses well in water with particle sizes ranging from 0.78 to 2.46 nm and exhibits excitation‐independent yellow fluorescent emission (529 nm), high quantum yield (44.3 %) and good biocompatibility. More importantly, the fluorescence of RB‐CQDs can be selectively quenched by Fe3+ ions with good linear correlation and the detection limit is 19.9 nM. The recoveries of this method in actual water samples are 90 % to 110 % with relative standard deviations less than 5 %. [ABSTRACT FROM AUTHOR]

Although membrane separation technology has been widely used in the treatment of oily wastewater, the complexity and high cost of the membrane preparation, as well as its poor stability, limit its further development. In this study, via the vacuum-assisted suction filtration method, polydopamine (PDA)-coated TiO2 nanoparticles were tightly attached and embedded on both sides of laboratory filter paper (FP). The resultant FP possessed the typical wettability of high hydrophilicity in the air with the water contact angle (WCA) of 28°, superoleophilicity with the oil contact angle (OCA) close to 0°, underwater superoleophobicity with the underwater OCA greater than 150°, and superhydrophobicity under the water with the underoil WCA over 150° for five kinds of organic solvents (carbon tetrachloride, toluene, n-hexane, n-octane, and iso-octane). The separation efficiency of immiscible oil/water, oil-in-water, and water-in-oil emulsions using the modified FP is higher than 99%. After 17 cycles of emulsion separation, a high separation efficiency of 99% was still maintained for the FP, along with good chemical and mechanical stability. In addition, successful separation and purification were also realized for the oil-in-water emulsion that contained the methylene blue (MB) dye, along with the complete degradation of MB in an aqueous solution under UV irradiation. [ABSTRACT FROM AUTHOR]

Membrane separation is a very promising and economical method for gravitational oil/water separation and the collection of oil spills. Both superhydrophilicity/underwater superhydrophobicity (SHL&UWSOB) and superhydrophobicity/superlipophilicity (SHB&SOL) are suitable materials for the solution. In this work, an ingenious design strategy of "two birds with one stone" to modify Ni foams (NFs) was developed, in which SHL&UWSOB was initially fabricated by the in situ growth of a bimetallic Fe/Ni-MOF on an NF surface by solvothermal synthesis. Further modification based on the resultant SHL&UWSOB-NF led to the construction of a SHB&SOL surface by simple immersion of stearic acid. The micro/nano structure beneficial to underwater superoleophobicity was tailored by optimizing the solvothermal reaction time in the range of 10–24 h. The results showed that SHL&UWSOB-NF was obtained with a high oil contact angle (OCA) of 165.9° under water when the time of the solvothermal reaction was kept at about 18 h. Likewise, the further modified NF exhibited an obvious SHB&SOL property with a water contact angle (WCA) of 156.3° and a water rolling angle (SCA) of 9°. The light oil (n-hexane) floating on the water's surface and heavy oil of carbon tetrachloride (CCl4) at the bottom of the water, as well as the mini-separation of oil/water, demonstrated its facile and versatile application as a separation medium. The strategy may offer new approaches for the fabrication of superwetting/superantiwetting separation materials for oil/water separation and oil collection. [ABSTRACT FROM AUTHOR]

Ru-Catalyzed aromatic C–H bond activation and functionalization have emerged as important topics because they have resulted in remarkable progress in organic synthesis. Both experimental and theoretical studies of their mechanisms are important for the design of new synthetic methodologies. In this review, a mechanistic view of the Ru-mediated C–H bond cleavage step is first given to reveal the C–H bond activation modes, including oxidative addition, metathesis and base-assisted deprotonation. In this process, directing groups play an important role in determining the reactivity of the C–H bond. The C–H bond activation generally leads to the formation of a Ru–C bond, which is further functionalized in the subsequent steps. The mechanisms of Ru-catalyzed arylation, alkylation, and alkenylation of arenes are summarized, and these transformations can be categorized into cross-coupling with electrophiles or oxidative coupling with nucleophiles. In addition, the mechanism of ortho-ruthenation-enabled remote C–H bond functionalization is also discussed. [ABSTRACT FROM AUTHOR]

A hybrid material of metal organic frameworks (MOFs) and monoliths was developed and used for stir bar sorption extraction (SBSE) of five sulfonylurea herbicides. It was prepared in a glass tube (4 mm I.D.) by thermal polymerization using modified neodymium supermagnetic (Nd 2 Fe 14 B) powders as the component substrates, the organic polymerization solutions and ethyl cellulose as the adhesion agent. The prepared stir bar was characterized by scanning electron micrography (SEM) and X-ray diffraction (XRD). It was successfully applied for the determination of sulfonylurea herbicides in soil and lake water samples coupled with high-performance liquid chromatography (HPLC). The extraction and desorption factors affecting the performance of sulfonylurea herbicides were evaluated in detail. Under the optimum conditions, the extraction efficiency of the hybrid stir bar was obviously higher than the blank stir bar without UIO-66(Zr)-NH 2 . Linear ranges were 10–700 μg/L for thifensulfuron-methyl (TIM), amidosulfuron (AS) and metsulfuron-methyl (MSM) and 10–800 μg/L for sulfosulfuron (SSF) and tribenuron-methyl (TBM), respectively. The obtained detection limits were in the ranges of 0.04–0.84 μg/L with the recoveries of 68.8–98.1% for the real samples. The novel stir bar possessed excellent advantages of both supermagnetic performance and large specific surface areas in the presence of MOFs and monoliths, which was potentially an optimal adsorbent for environmental analysis. [ABSTRACT FROM AUTHOR]

A visible-light-promoted direct thiolation of α-C(sp3)–H in ethers with thiosulfonates was developed for the preparation of α-arylthioethers using easily availably Na2-eosin Y and TBHP as a photocatalyst and oxidant. This reaction occurred smoothly under the irradiation of 5 W blue light at room temperature and generated the corresponding products in good to excellent yields. [ABSTRACT FROM AUTHOR]

An environmentally friendly strategy for the photo-catalyzed three-component reaction between quinoxalin-2(1H)-ones, vinylarenes, with inexpensive and easily accessible ethyl bromodifluoroacetate/sodium difluoromethanesulfinate is described. This protocol exhibits mild conditions, high efficiency, and excellent functional group tolerance, providing a highly efficient approach for the synthesis of difluorobenzylated quinoxalin-2(1H)-ones by the formation of two carbon-carbon bonds. A radical mechanism is responsible for this three-component transformation. [ABSTRACT FROM AUTHOR]

Selectivity control is a challenging and important subject in semihydrogenation of alkynes. Here, a combined theoretical and experimental study was performed to reveal the origin of the chemo- and stereoselectivity in cobalt-catalyzed stereodivergent semihydrogenation of alkynes. Three NNP and PNP type pincer ligands were considered in calculation. The computational results show that over-reduction of the alkene is forbidden in this catalytic system because the alkylcobalt(I) intermediate formed by alkene insertion prefers to undergo β -H elimination rather than protonation of the Co C bond. Distortion–interaction analysis along the reaction coordinate suggests that the higher distortion energy during methanol-mediated protonation of the alkylcobalt(I) species suppresses formation of the side product, thereby determined the chemoselectivity. Mechanistic investigation reveals that the active cobalt(I) hydride species formed by pre-catalyst [ C ] has strong catalytic activity for alkene isomerization. Subsequent control experiments combined with free energy comparison confirms this conclusion and reveals that fast deactivation of catalyst and the weaker reactivity of the cis-alkene intermediate in the presence of the alkyne substrate prevents Z / E alkene isomerization using pre-catalyst [ C ]. This results in the divergent stereoselectivity in the presence of different cobalt pincer complexes. [ABSTRACT FROM AUTHOR]

A novel ammonium iodide - promoted arylsulfonylation of quinones with sodium arylsulfinates has been explored. This reaction proceeded smoothly through unique nucleophilic addition reaction and produced the arylsulfonylation products in moderate to good yields. The reactions proceeded efficiently over a broad range of substrates with good regioselectivity and functional group tolerance. [ABSTRACT FROM AUTHOR]

A convenient and efficient copper-catalyzed oxidative arylation of quinoxalin-2(1H)-ones with 3-aminoindazoles is developed for the synthesis of cyanoarylated quinoxalin-2(1H)-ones. Notably, 3-aminoindazoles are employed as efficient arylating agents via the cleavage of two C–N bonds. This oxidative arylation of quinoxalin-2(1H)-ones involves a radical process and undergoes a sequence of 3-aminoindazole oxidation, two C–N bond cleavage, and cyanoaryl radical addition. [ABSTRACT FROM AUTHOR]

A Cu(OAc) 2 -catalyzed synthesis of 2-arylquinoline N -oxides with easily available arylamines is described. The main features of this reaction are mild reaction conditions, high functional-group tolerance, excellent regioselectivity, and good to excellent yields. This procedure is mild, operationally simple, and constitutes a greener approach to the arylation of quinoline N -oxides. [ABSTRACT FROM AUTHOR]

[Display omitted] • We explored mechanisms of Cu 2 O-catalyzed electroreduction of CO 2 with both periodic boundary and saturation cluster models. • We developed a method simulating the impact of an electric field and employed it to probe the ongoing reaction. • We considered the solid–liquid interface by introducing solvent molecules and buffer ions into our analysis. The imperative need to reduce atmospheric CO 2 to mitigate global warming and advance sustainable energy systems has driven extensive research. Copper oxide (Cu 2 O) has emerged as a promising catalyst for electroreduction of CO 2 , yet its catalytic mechanism remains debated. This study employs a theoretical approach to delve into the intricate details of CO 2 electroreduction catalyzed by Cu 2 O. Utilizing both periodic boundary and saturation cluster models, we explore various reaction pathways, successfully identifying key transition states and intermediates with each model. A comprehensive analysis and comparison of results from both models are conducted. To enhance understanding, we develop a method simulating the impact of an electric field, employed to probe the ongoing reaction. Additionally, we consider the solid–liquid interface by introducing solvent molecules and buffer ions into our analysis. This comprehensive theoretical investigation aims to elucidate the mechanism governing the electroreduction of CO 2 catalyzed by Cu 2 O and analogous semiconductor oxides, providing valuable insights into this critical process. [ABSTRACT FROM AUTHOR]

A visible-light-catalyzed difluoroacetylated spirocyclization of N-arylpropiolamides with ethyl bromodifluoroacetate as a CF2CO2Et radical precursor is described. This approach allows the formation of two carbon–carbon bonds and one carbon–oxygen bond in a single reaction through a sequence of C–H oxidative coupling, ipso-cyclization and dearomatization processes. This protocol affords a straightforward route to synthesize CF2CO2Et-containing spiro[4.5]trienones in moderate to good yields. [ABSTRACT FROM AUTHOR]

A general visible-light-induced catalyst-/additive-free strategy was developed for the construction of various aroylated heterocycles (55 examples, up to 95% yield, including modification of pharmaceuticals and natural products) such as thioflavones, benzimidazo[2,1-a]isoquinolin-6(5H)-ones, indolo[2,1-a]isoquinolin-6(5H)ones, quaternary 3,3-dialkyl 2-oxindoles, quinoxalin-2(1H)-ones, and benzo[e][1,2,3]oxathiazine 2,2-dioxides in a green solvent (dimethyl carbonate) under air and room temperature conditions. This practical acylation process was achieved using 4-acyl-1,4-dihydropyridines (acyl-DHPs) as acylating reagents under mild conditions, avoiding the use of catalysts, bases, additional oxidants, and traditional organic solvents. [ABSTRACT FROM AUTHOR]

A practical and efficient synthetic route to construct a variety of 3-arylselenenyl/3-arylthio spiro[4.5]trienones was developed using Selectfluor reagent as a mild oxidant. This reaction proceeds via a sequence of electrophilic cation addition, spirocyclization and dearomatization, then offers an approach to introduce Se/S-centered cation into the C–C triple bonds. The utility of this protocol were justified by the excellent compatibility of a wide range of functional groups, good yields and scalability under mild reaction conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 4-MPBA-MoS 2 QDs was synthesized by one-pot hydrothermal approach. • The prepared QDs have a uniform spherical appearance with a diameter of 1.5 ∼ 3.0 nm. • Inhibitory effects of the QDs on BSA amyloid aggregation were investigated. • Molecular docking reveals the mechanism of QDs inhibiting BSA amyloid aggregation. In recent years, seeking and screening of compounds that can inhibit and/or depolymerize protein aggregation has been a hot issue in the field of pharmaceutical research. As a new material, quantum dots have been widely concerned by medical researchers. In present study, a novel 4-mercaptophenylboronic acid functionalized MoS 2 quantum dots (4-MPBA-MoS 2 QDs) was successfully synthesized through a one-pot hydrothermal approach by using molybdate dehydrate and 4-mercaptophenylboronic acid as Mo and S source, respectively. Transmission electron microscopy observation showed that the morphology and microstructure of the 4-MPBA-MoS 2 QDs displayed uniform spherical shape with a diameter of approximately 1.5 ∼ 3.0 nm. The UV and fluorescence spectra experiments indicated that the prepared QDs had good water solubility and two weak absorption peaks were appeared at 280 nm and 310 nm. When the excitation wavelength was set to 310 nm, the 4-MPBA-MoS 2 QDs had the strongest fluorescence intensity, and the maximum emission wavelength appeared at 405 nm. In vitro experiments showed that the 4-MPBA-MoS 2 QDs could significantly reduce the aggregation of bovine serum albumin (BSA). Especially when the mass ratio of BSA to 4-MPBA-MoS 2 QDs was 1:5, the inhibition rate could reach 76.4%. Cell experiment showed that the presence of 4-MPBA-MoS 2 QDs could obviously decrease the cytotoxicity induced by BSA amyloid fibrils. Moreover, the depolymerization of BSA amyloid fibrils by 4-MPBA-MoS 2 QDs and its excellent cell permeability were also observed. Molecular docking studies have shown that 4-MPBA-MoS 2 QDs may stabilize the BSA structure through van der Waals forces, hydrophobic force, electrostatic interactions and hydrogen bonds formed between the outer layer of 4-MPBA and BSA to prevent fibrosis aggregation. The results of this study suggested that 4-MPBA-MoS 2 QDs showed low cytotoxicity, good biocompatibility and solubility, and had a great potential in the design of new drugs for the treatment of amyloid-related diseases. [ABSTRACT FROM AUTHOR]

Design and fabrication of Janus interface materials as diodes for both liquids and gases are a great challenge in the field of materials science. Here, a Janus titanium mesh with superhydrophobicity and high oleophobicity was fabricated using economical and environmentally friendly electrochemical etching and wet-chemistry methods. Switchable, spontaneous, and unidirectional transport ability for both water and oil fluids was realized in the smart mesh by ultraviolet (UV) irradiation. Unidirectional fluid transport only occurred for fluids with specific surface tension values, and the fluid selectivity was dependent on the UV irradiation time. Underwater bubble unidirectional permeation through the mesh was also achieved using a mesh irradiated for approximately 7 h. More importantly, the mechanism is proposed and elucidated in detail, and the proposed mechanism can more reasonably explain the antigravity unidirectional transport of liquid droplets. [ABSTRACT FROM AUTHOR]

Abstract: Two less common lanthanide coordination polymers, [Ln2(fum)(malate)2(phen)2] n ·n1.25H2O (Ln=Eu, 1; Pr, 2. fum=fumarate, phen=1,10-phenanthroline) were synthesized and characterized by IR spectra and X-ray crystallography. Single crystal X-ray diffraction analysis shows that complex 1 is isostructural with complex 2. In the two complexes, we found a pair of enantiomers (R-malate and S-malate) which are obtained by addition reaction between maleate and water and fumarate which result from configurational tranformation of maleate. The two structures consist of coordination polymer chains along the c-axis which are held together solely through hydrogen bonding and π–π stacking. Three-dimension supramolecular structures are formed through the two types of weak interaction. The IR data are also described and compared with those of other similar complexes. [Copyright &y& Elsevier]

In the work described in this paper, 7-hydroxyflavone and chrysin were phosphoylated by a modified Atheron–Todd reaction. Three new phosphorylated flavonoids (PF) were obtained, and the structures of the target products were determined by X-ray and NMR data and electrospray ionization (ESI) tandem mass spectroscopy (MS). The mixed solutions of the phosphorylated flavonoids and different proteins such as insulin, lysozyme, and cytochrome c were injected in an ion trap mass spectrometer. The results show that all the phosphorylated flavonoids could form non-covalent complexes with the proteins mentioned above, while non-covalent complexes were not detected from the mixed solution of the chrysin or 7-hydroxyflavone with proteins. The research shows that the phosphorylated flavonoids could enhance the interaction with proteins. It may imply their important role in biological processes. The method described in this paper provides us additional information for studying such interactions for phosphorylated flavonoids in this important field. [Copyright &y& Elsevier]

A metal-free photocatalytic strategy for the preparation of thiocyanated heterocycles from inexpensive NH4SCN has been developed using carbon nitride (g-C3N4) as a general heterogeneous catalyst in a green solvent under an air atmosphere and the irradiation of a blue LED. Various thiocyanated heterocycles including indolo[2,1-a]isoquinolin-6(5H)-ones, benzimidazo[2,1-a]isoquinolin-6(5H)-ones, thioflavones, azaspiro[4.5]trienones and imidazo[1,2-a]pyridines were successfully synthesized in good yields (up to 96%). Importantly, this metal-free and external-oxidant-free procedure employed dimethyl carbonate as a green medium, avoiding the traditional volatile organic solvents. Moreover, the recyclable g-C3N4 catalyst could be used at least 8 times without significant loss of activities. [ABSTRACT FROM AUTHOR]

Weaning is the gradual process of introducing solids or semisolid foods into an infant's diet, in order to ensure their healthy growth. This study developed two kinds of formula weaning food based on roasted or extruded quinoa and millet flour, and evaluated their quality. A fructo‐oligosaccharide (FOS)/galacto‐oligosaccharide (GOS) mix was added to provide the prebiotic potential. The protein contents of the roasted quinoa‐millet complementary food (RQMCF) and extruded quinoa‐millet complementary food (EQMCF) were 16.7% and 17.74% higher, respectively, than that of commercial millet complementary food (CMCF). Both RQMCF and EQMCF provided sufficient levels of energy and minerals. Extrusion provided the foods with a lower viscosity, and higher solubility and water absorption ability than roasting. In vitro digestion results showed that EQMCF exhibited the highest starch and protein digestibility (89.76% and 88.72%, respectively) followed by RQMCF (87.75% and 86.63%) and CMCF (83.35% and 81.54%). The digestas of RQMCF and EQMCF after in vitro digestion exhibited prebiotic effects by promoting the growth of the probiotics (Lactobacillus plantarum and Lactobacillus delbrueckii). These results will contribute to developing complementary weaning foods for infants. Practical Application: This study has shown that extrusion is an efficient and stable processing method for producing infant complementary foods with low density, balanced nutrition, and high levels of starch and protein digestibility. Extruded quinoa‐millet prebiotic complementary food can also promote the proliferation of probiotics. This will provide a new direction for developing novel infant formula weaning foods. [ABSTRACT FROM AUTHOR]

Three new CdII coordination polymers (CPs) have been synthesized by hydrothermal reactions of Cd(OAc)2, 1,2,5‐thiadiazole‐3,4‐dicarboxylic acid (H2tdzdc), and distinct N/O‐donor ligands. They exhibit two‐dimensional (2D) and three‐dimensional (3D) structures with different topology networks including rob, zzx, and cem. The introduction of 4,4‐bipyridine (4,4‐bipy), [4,4‐bipyridine]1,1‐dioxide (Obpy), and 1,4‐bis((1H‐1,2,4‐triazol‐1‐yl)methyl)benzene (tmb) is a favor for the construction of interpenetrated networks. Moreover, the luminescent properties of 1, 2, and 3 have been investigated in detail by experiment and theoretical methods. Density functional theory (DFT) calculations indicate that the electron would be transferred from metal to ligand in the excitation of compound 3. [ABSTRACT FROM AUTHOR]

In the presence of multiple electrophiles, the reaction sequence is a critical mechanistic problem. Here, we report a theoretical study on the mechanism of phosphine-catalyzed [8+2] cycloaddition of heptafulvenes and allenoate. DFT calculations showed that electrophilicity is the barrier for nucleophilic attack, while it fails in the prediction of priority. [ABSTRACT FROM AUTHOR]

Water, as a green reaction medium, is safe, non-toxic, and rich in reserves on Earth, while visible light represents a renewable, clean, and abundant energy source. Organic transformations carried out under the irradiation of visible light in water are undoubtedly more attractive, and are in line with the concept of "green chemistry" to effectively minimize the environmental impact of chemical synthesis. This review focuses on the recent progress in visible-light-mediated organic transformations in water, and the related mechanisms are also discussed. Although great achievements have been made, they are just the tip of the iceberg and there is still great room for improvement. This review will facilitate the understanding of visible-light-mediated organic transformations in water and further stimulate the advancement of more novel relevant strategies. [ABSTRACT FROM AUTHOR]

Through direct coupling reaction of azine N‐oxides with readily available pyridin‐2(1H)‐ones, a facial and practical strategy was developed for the synthesis of 1‐azine‐pyridin‐2(1H)‐one derivatives in the presence of diethyl H‐phosphonate, CCl4 and Et3N at room temperature for 0.5 h. This reaction features metal‐free and mild reaction conditions, short reaction time, ease of scale up and wide scope of products. [ABSTRACT FROM AUTHOR]

Microwave-assisted synthesis of polyheterocyclic-fused quinoline-2-thiones through the annulation of ortho-heteroaryl anilines and CS2 was realized in water without using any catalysts and additives. The desired products were obtained in high yields through simple filtration. A remarkable E-factor of 0.45 and an EcoScale score of 85.5 were obtained. [ABSTRACT FROM AUTHOR]

A sustainable and cost‐effective protocol for direct aminomethylation of imidazo‐fused heterocycles by decarboxylative coupling reaction of N‐phenylglycines with imidazo‐fused heterocycles in the presence of CsPbBr3 under the irradiation of visible light has been developed. This is the first example of CsPbBr3‐catalyzed aminomethylation of imidazo‐fused heterocycles. The eminent advantage of this work is in that, CsPbBr3 is easily prepared and can be used at least 5 times without obvious reduction in its activity, exhibiting high catalyst economic feature. [ABSTRACT FROM AUTHOR]

A mixture of pathways including the use of catalyst was proposed for a dirhodium-mediated triazole activation–cycloaddition. This proposal was supported by the results of density functional theory (DFT) calculations, and was indicated to involve a non-catalyzed cleavage of the triazole N–N bond followed by a dirhodium-assisted denitrogenation. Electron-deficient carboxylates were found to be favourable for the rate-determining denitrogenation step. [ABSTRACT FROM AUTHOR]

Tanreqing injection is a Chinese medical formula used to treatment of respiratory diseases. In our study, we developed a feasible and accurate strategy applying an ultra-high-performance liquid chromatography coupled with Q Exactive™ Plus-Orbitrap Fusion mass spectrometers (UPLC-Q-Orbitrap Fusion MS/MS) to clarify and quantify the chemical profiling of Tanreqing injection rapidly. A total of 80 ingredients were identified by comparing the accurate mass, fragment ions, and cleavage pathways, including flavonoids, phenyl propionic acid, coumarins, amino acids, cholesterol, etc. And 18 characteristic components among them were definitely identified by comparison with reference substance. Meanwhile, the 18 representative constituents were simultaneously measured in eight batches Tanreqing injection utilizing UPLC-Q-Orbitrap Fusion MS/MS in negative ion mode. Among the 18 components, beta-d-glucopyranosiduronic acid, baicalin, ursodeoxycholic acid, and chenodeoxycholic acid were the predominant constituents. In principal components analysis results, five dominating components were extracted, and the variant contribution rates were ranked as: 37.86, 22.86, 16.42, 9.80, 7.32%, with the accumulated value 94.26%. 5-caffeoylquinic acid, isochlorogenic acid C, and baicalin possessed larger loads on the first factor. Our research carried out qualitative and quantitative analysis on Tanreqing injection, provided a certain reference for the research on pharmacodynamic material basis and the selection of quality markers. [ABSTRACT FROM AUTHOR]

A Mn(III)‐mediated radical cyclization reaction of o‐vinylaryl isocyanides and arylboronic acids or diphenylphosphine oxides to access various 2‐functionalized quinolines under mild conditions was developed. With the introduction of radical stabilizing substituents (e. g. aryl and methyl group) on vinyl group, this reaction provides a regiospecific 6‐endo‐trig radical cyclization of o‐vinylaryl isocyanides, giving a number of structurally unique and biologically potential 2‐functionalized quinoline derivatives. [ABSTRACT FROM AUTHOR]

(R/S)-4,4′-Dimethoxy-5,6,5′,6′-dimethenedioxy-2,2′-di-(4(S)-methyl-oxazoline-1)-biphenyl has been synthesized from dimethyl-4,4′-dimethoxy-5,6,5′,6′-dimethenedioxy-biphenyl-2,2′-dicarboxylate, and then the diastereoisomer mixture was almost fully converted to a single diastereoisomer with S-configuration ((S)-3) through the key configuration transform promoted by CuI, which was confirmed by CD, HPLC and 13C NMR. The C2-symmetric biphenyl, (S)-dimethyl-4,4′-dimethoxy-5,6,5′,6′-dimethenedioxy-biphenyl-2,2′-dicarboxylate was prepared easily via the hydrolysis and ester exchange of (S)-3. [Copyright &y& Elsevier]

A novel temperature-dependent synthesis of organic sulfones from t-butylsulfinamide and alkenes under aerobic CuSO4-phosphorous acid catalyzed conditions was developed. Via this newly developed method, a series of vinyl sulfones and β-hydroxy sulfones were synthesized at 120 °C and 40 °C, respectively. [ABSTRACT FROM AUTHOR]

A metal‐free visible‐light‐induced cyclization procedure was developed for the rapid synthesis of perfluoroalkyl‐substituted benzimidazo[2,1‐a]isoquinolin‐6(5H)‐ones and perfluoroalkyl‐substituted indolo[2,1‐a]isoquinolin‐6(5H)‐ones under mild reaction conditions. In this procedure, the formation of electron‐donor‐acceptor (EDA) complex is critical for the visible‐light promoted process to avoid the utilization of external photocatalysts. [ABSTRACT FROM AUTHOR]

Herein, a novel fluorescence method is reported for the detection of T4 polynucleotide kinase (T4 PNK) based on a FRET between dye-labeled DNA and polydopamine nanotubes (PDANTs). PDANTs can bind and quench the fluorescent dye-labeled single-stranded DNA (ssDNA) probes, whereas they have low affinity towards double-stranded DNA (dsDNA). In the presence of T4 PNK and ATP, λ exonuclease initiated the hydrolysis of the 5-phosphoryl termini of dsDNA and released ssDNA, which could strongly adsorb on the PDANTs and decrease the fluorescence intensity; on the basis of this concept, we successfully established a method for the detection of T4 PNK. The method displayed the detection limit of 0.01 U mL−1 with a linear range from 0.01 to 50 U mL−1. In addition, we investigated the effect of several inhibitors including Na2HPO4, (NH4)2SO4 and NaCl. The method provides a platform for the detection of T4 PNK and evaluation of inhibitors. [ABSTRACT FROM AUTHOR]

A metal-free cascade reaction was developed for the synthesis of indolo[1,2-a]quinoline derivatives from arylsulfonyl hydrazides and 1-(2-(arylethynyl)phenyl)indoles in the presence of TBAI/TBHP. Impressively, these products exhibit excellent fluorescence properties, which is promising for cell imaging. [ABSTRACT FROM AUTHOR]

As a new type of bifunctional catalyst, the Lewis acid transition‐metal (LA‐TM) catalysts have been widely applied for hydrogen activation. This study presents a mechanistic framework to understand the LA‐TM‐catalyzed H2 activation through DFT studies. The mer(trans)‐homolytic cleavage, the fac(cis)‐homolytic cleavage, the synergetic heterolytic cleavage, and the dissociative heterolytic cleavage should be taken as general mechanisms for the field of LA‐TM catalysis. Four typical LA‐TM catalysts, the Z‐type κ4‐L3B‐Rh complex tri(azaindolyl)borane‐Rh, the X‐type κ3‐L2B‐Co complex bis‐phosphino‐boryl (PBP)‐Co, the η2‐BC‐type κ3‐L2B‐Pd complex diphosphine‐borane (DPB)‐Pd, and the Z‐type κ2‐LB‐Pt complex (boryl)iminomethane (BIM)‐Pt are selected as representative models to systematically illustrate their mechanistic features and explore the influencing factors on mechanistic variations. Our results indicate that the tri(azaindolyl)borane‐Rh catalyst favors the synergetic heterolytic mechanism; the PBP‐Co catalyst prefers the mer(trans)‐homolytic mechanism; the DPB‐Pd catalyst operates through the fac(cis)‐homolytic mechanism, whereas the BIM‐Pt catalyst tends to undergo the dissociative heterolytic mechanism. The mechanistic variations are determined by the coordination geometry, the LA‐TM bonding nature, the electronic structure of the TM center, and the flexibility or steric effect of the LA ligands. The presented mechanistic framework should provide helpful guidelines for LA‐TM catalyst design and reaction developments. [ABSTRACT FROM AUTHOR]

An efficient and simple protocol for Selectfluor‐mediated phosphonation of quinoxalin‐2(1H)‐ones with dialkyl H‐phosphonates has been developed under base and transition‐metal free conditions, affording the desired 3‐phosphorylated quinoxalin‐2(1H)‐ones in good to excellent yields. This method has the advatages of broad substrate scope, general functional groups compatibility, and mild reaction conditions. [ABSTRACT FROM AUTHOR]

A convenient radical cascade cyclization of aniline‐linked 1,7‐enynes with 1,3‐dicarbonyl compounds was developed to synthesize cyclopenta[c]quinolines in the presence of AgNO3/K2S2O8. A wide range of cyclopenta[c]quinolines were prepared in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

An efficient and practical one‐pot strategy for the synthesis of N‐sulfonylformamidines was developed by directly using easily available sulfonyl chlorides, sodium azide and tertiary/secondary amines in the presence of 5 mol‐% CuBr2 under aerobic oxidative conditions. [ABSTRACT FROM AUTHOR]

Visible-light-promoted sulfidation and phosphorylation of arylhydrazines for the synthesis of aromatic sulfides and diarylphosphoryl hydrazides were developed using the organic dyes rose bengal and Na2-eosin Y as photocatalysts, respectively. This strategy offers an efficient and mild transition-metal-free synthetic protocol for the formation of C–S and N–P bonds from arylhydrazines. [ABSTRACT FROM AUTHOR]

A silver-mediated phosphorylation/cyclization of N-allylbenzamides with phosphine oxides for the synthesis of phosphoryl-substituted dihydroisoquinolones was developed. This protocol features broad substrate scope, experimental simplicity, high efficiency, step-economy, and facile scalability. [ABSTRACT FROM AUTHOR]

A transition‐metal‐free visible‐light‐promoted radical phosphorylation/cyclization of N‐allylbenzamides with phosphine oxides for the synthesis of phosphoryl‐substituted dihydroisoquinolones was developed under room temperature. This protocol features mild reaction conditions, simple operation, broad substrate scope as well as scale‐up ability. [ABSTRACT FROM AUTHOR]