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d-Allulose is considered an ideal alternative to sucrose and has shown tremendous application potential in many fields. Recently, most efforts on production of d-allulose have focused on in vitro enzyme-catalyzed epimerization of cheap hexoses. Here, we proposed an approach to efficiently produce d-allulose through fermentation using metabolically engineered Escherichia coli JM109 (DE3), in which a SecY (ΔP) channel and a d-allulose 3-epimerase (DPEase) were co-expressed, ensuring that d-fructose could be transported in its nonphosphorylated form and then converted into d-allulose by cells. Further deletion of fruA, manXYZ, mak, galE, and fruK and the use of Ni2+ in a medium limited the carbon flux flowing into the byproduct-generating pathways and the Embden-Meyerhof-Parnas (EMP) pathway, achieving a ≈ 0.95 g/g yield of d-allulose on d-fructose using E. coli (DPEase, SecY [ΔP], ΔFruA, ΔManXYZ, ΔMak, ΔGalE, ΔFruK) and 8 μM Ni2+. In fed-batch fermentation, the titer of d-allulose reached ≈23.3 g/L.

LaBO3 (B = Fe, Mn, and FeMn) perovskite-type oxides were prepared by sol–gel method and then used as catalysts in CO hydrogenation for light olefins. The catalysts were characterized using XRD, H2-TPR, SEM, CO (CO2)-TPD, and XPS. The results showed that the lattice oxygen migration and oxygen vacancies promoted oxygen mobility by doping Mn2+ at the B site, Moreover, the presence of manganese as a promoter in the catalyst increased olefin selectivity compared with the olefin selectivity of the catalyst containing iron at the B-site and exhibited resistance to carbon deposition; while reducing the metal elements. In CO hydrogenation, potassium-promoted LaFeMnO3 catalysts afforded high catalytic activity and C2=–C4= selectivity. An O/P value of 5.0 and a C2=–C4= fraction of 54% were achieved for all hydrocarbons with low methane selectivity.

Glioma is one of the most lethal and complex tumors, and thus, an effective drug delivery system must selectively target the tumor sites and release its cargos in a controlled manner. For the first time, we combined chemotherapeutic agent doxorubicin (DOX) and chemosensitizer lonidamine (LND) to synergistically treat glioma. We also designed and prepared multitargeted redox-sensitive liposomes (Lip-SPG) co-modified with glucose and triphenylphosphonium (TPP) to effectively deliver DOX and LND for anti-glioma therapy. The anti-glioma evaluation shows that DOX and LND have a synergistic effect and Lip-SPG could further enhance their cooperation. In vitro, Lip-SPG could increase the cellular uptake and mitochondrial uptake on bEnd.3 cells and C6 cells with multitargeting ability on the brain, tumor, and mitochondria mediated by glucose and TPP. Lip-SPG can also escape from lysosomes before entering the mitochondria. The anti-glioma efficacy in vitro shows that Lip-SPG can inhibit tumor cell proliferation and induce apoptosis. In addition, Lip-SPG have a remarkable interference to mitochondria, such as reducing intracellular ATP production, inducing ROS generation, and promoting mitochondrial membrane potential depolarization. Furthermore, in vivo, the introduction of PEGylation via glutathione-sensitive disulfide bonds endows Lip-SPG with favorable pharmacokinetic properties, brain targeting ability, low toxicity to normal tissues, and great anti-glioma efficacy with the survival time extended from 19 to 39 days. In conclusion, Lip-SPG are an effective delivery system for synergistically treating glioma with DOX and LND.

Inspired by the diversity created by nature, organic chemists have been using a divergent strategy to improve the synthetic efficiency of diverse molecules. Transition-metal-catalyzed C-H functionalization has become one of the most straightforward, powerful, and atom-economical methods to construct complex scaffolds. However, C-H activation initiated divergent transformation to prepare diverse molecules is still limited. To address this challenge, we herein developed Rh(III)-catalyzed C-H olefination/annulation reaction cascades to divergently construct diverse polyheterocycles by tuning manipulations of directing groups (DGs). Up to 9 distinct scaffolds were creatively synthesized under simple conditions with good functional group tolerance, chemo-, and regioselectivity. Such a versatile strategy and its extension may encourage researchers to discover more promising manipulations of DGs for transition-metal-catalyzed C-H bond activation, making diverse available targets and materials that would have been previously out of range.

The satisfactory efficient tumor treatment and complete tumor ablation using a mono-therapeutic approach are limited owing to the tumor complexity, diversity, heterogeneity and the multiple pathways involved in tumor pathogenesis. Herein, novel, intelligent and tumor microenvironment (TME)-responsive biotin/R8 peptide co-modified nanocarriers (BRNC) loading paclitaxel (PTX)/glucose oxidase (GOx) were constructed. GOx could catalyze the oxidation of intracellular glucose to gluconic acid and poisonous H2O2 to cause the deterioration of the tumor survival microenvironment, simultaneously achieving starvation and oxidation therapy. The acidic amplification during the GOx-mediated oxidation progress could in turn accelerate the cleavage of the acid-degradable hydrazone bond, promoting the deep penetration of nanocarriers into tumors. Even better, the aforementioned two aspects further increased the tumors' sensitivity to chemotherapeutic agents. Both in vitro and in vivo investigations indicated that the co-administration of GOx-BRNC and PTX-BRNC can remarkably improve the therapeutic efficacy and reduce side effects through the high-specific tumor targeting multimodal synergistic starvation/oxidation/chemotherapy, which would be a promising strategy for the next generation cancer therapy.

To reveal the regularity of arsenic adsorption of sediment, this study explores the law of arsenic adsorption by sediment when Fe3+ and Mn2+ coexist. The experimental results fit the first-order kinetic model and the second-order kinetic model. The surface physicochemical properties of sediment particles were analysed by scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherm and fractal dimension. Characterization of surface area and pore distribution were measured by the BET equation and BJH equation. The results illustrate that the adsorption of arsenic by sediment shows the phenomenon of rapid adsorption in the early stage, slow adsorption in the middle stage and finally adsorption equilibrium. In the presence of coexisting ions, the BET specific surface area was as high as 20.14m2/g, the pore volume as 0.047826cm3/g, the surface pore volume as 43.25cm3, and the surface fractal dimension Ds as the largest.

Purpose: To evaluate the cytotoxic effect of essential oil derived from Chenopodium ambrosioides L. in Sichuan Province on human liver cancer SMMC-7721 cells, as well as its possible molecular mechanisms.Methods: Cytotoxicity was characterized by MTT assay and transmission electron microscopy (TEM) of SMMC-7721 cells ultrastructure. The apoptotic effect of the essential oil was evaluated by changes in mitochondrial membrane potential and Western blot assay.Results: MTT assay data indicate that the essential oil was cytotoxic to SMMC-7721 cells, while TEN revealed that there were vacuoles and nucleus fragmentation in the SMMC-7721 cell cytosol, cell swelling, and a large amount of leakage. Mitochondrial membrane potential assay and Western Blot data indicate that the essential oil induced cell apoptosis.Conclusion: The essential oil of Chenopodium ambrosioides L. in Sichuan Province seems to induce apoptosis of human liver cancer SMMC-7721 cells via the mitochondrial-mediated pathway and endoplasmic reticulum stress. Thus, this plant requires further investigation as a potential source of ananti-liver cancer drug. Keywords: Chenopodium ambrosioides Essential oil; Anti-tumor activity, Liver cancer Apoptosis, SMMC-7721 cells

Synthesis of model compound of [FeFe]-hydrogenase active site is a promising and effective method to produce hydrogen. [μ-(SCH(CH2CH3)CH2S)–Fe2(CO)5]2-(κ1-DPPE) (compound 1) and [μ-(SCH(CH2CH3)CH2S)] Fe2(CO)5 (κ1-DPPM) (compound 2) were designed and synthesized. Compared 1 and 2 via IR, X-ray single crystal diffraction and CV, it was found that even through 1 and 2 shared similar electronic environment as well as crystal structure features, 1 with two symmetric [2Fe–2S] subsites had distinct reduction peaks and also showed higher electrocatalytic proton reduction efficiency in the presence of equivalent amount of HOAc, which indicated two symmetric [2Fe–2S] subsites played different roles in the process of proton reduction. Furthermore, -(κ1-DPPE)-[2Fe–2S] moiety with variable valence state in 1 can mimic the [4Fe–4S] cluster and serve as an electron shuttle.

An unprecedented synthesis of 4-ethenyl quinazolines via a Rh(III)-catalyzed C–H activation and annulation reaction was described. In particular, when C-alkyl imidamides are benzyl groups, 2-benzoyl quinazolines can be obtained. This protocol enables the effective application of cyclopropenones, featuring high atom efficiency, broad substrate scope and mild reaction conditions.

A ruthenium(II)-catalyzed [5 + 1] annulation reaction between 2-arylanilines and cyclopropenones employing a free amine as a directing group has been developed. This protocol provides a facile and practical method for the preparation of a variety of biologically valuable 6-ethenyl phenanthridine scaffolds, and features the use of the cost-effective ruthenium catalyst, good functional group tolerance and no requirement of an external oxidant.

Globally, the accelerating use of renewable energy sources, enabled by increased efficiencies and reduced costs, and driven by the need to mitigate the effects of climate change, has significantly increased research in the areas of renewable energy production, storage, distribution and end-use. Central to this discussion is the use of hydrogen, as a clean, efficient energy vector for energy storage. This review, by experts of Task 32, “Hydrogen-based Energy Storage” of the International Energy Agency, Hydrogen TCP, reports on the development over the last 6 years of hydrogen storage materials, methods and techniques, including electrochemical and thermal storage systems. An overview is given on the background to the various methods, the current state of development and the future prospects. The following areas are covered; porous materials, liquid hydrogen carriers, complex hydrides, intermetallic hydrides, electrochemical storage of energy, thermal energy storage, hydrogen energy systems and an outlook is presented for future prospects and research on hydrogen-based energy storage. © 2020 The Authors

FeI2(CO)3PPh3, which usually used as the precursor of [Fe]-hydrogenase, was firstly used as catalyst in one-step hydroxylation of phenol to dihydroxybenzenes. It was found that the reaction can be conducted smoothly in aqueous phase at ambient temperature (25 °C). In the optimum conditions, the conversion of phenol is 26.7% and selectivity of DHB is 80.0%. The possible mechanism was investigated and proposed. The apparent kinetics study shows that it is a pseudo second order reaction and activation energy Ea is 66.36 kJ/mol.

Super high molecular weight copolymers of AM/NaA/AMPS were prepared by oxidation–reduction [OR-P(AM/NaA/AMPS)] and controlled radical polymerization [CR-P(AM/NaA/AMPS)]. The resulting copolymers were fully characterized, and the reaction conditions for their preparation were optimized. OR-P(AM/NaA/AMPS), CR-P(AM/NaA/AMPS), and conventional partially hydrolyzed polyacrylamide (HPAM) in brine solution were comprehensively characterized by thermogravimetric analysis, scanning electron microscopy, atomic force microscopy, and dynamic light scattering. OR-P(AM/NaA/AMPS) and CR-P(AM/NaA/AMPS) containing AMPS monomer showed better salt resistance, temperature tolerance, and viscosification property than the conventional HPAM polymer, making them more promising for enhanced oil recovery. Through comprehensive comparison and analysis, it was found that OR-P(AM/NaA/AMPS) was more conducive for high-temperature condition due to the existence of xanthone in OR-P(AM/NaA/AMPS). On the other hand, CR-P(AM/NaA/AMPS) was more suitable for high-mineral atmosphere, which could be attributed to its higher intrinsic viscosity.

Fine tuning of the structures and properties of hydrogen-bonded organic frameworks (HOFs) has been considered to be a huge challenge. Herein, we reported the controlled synthesis of meso-tetrakis(c...

A mild and recyclable protocol to synthesize 1,2-benzothiazines by Rh(III)-catalyzed C–H activation/cyclization of NH-sulfoximines in ionic liquids with high yields is described. A broad substrate ...

The first example of transition-metal-catalyzed C-H activations of 2-phenylisatogens with alkynes and sulfonyl azides has been developed using N-oxide as the directing group. Ru(ii)-Catalyzed C-H alkenylation/cyclization and Ir(iii)-catalyzed direct C-H sulfamidation proceeded with good yields and excellent functional group tolerance. Importantly, these two transformations provided straightforward routes for the synthesis of indol-3-one derivatives and sulfamidated 2-phenylisatogens respectively, which might be of considerable bioactivities.

The protonation of different functional acidic and alkalic groups is of utmost importance for the crystal engineering field. By using hydrochloric acid, in this work, the amine group of 3-aminobenzoic acid (1, C7H7NO2) and the hydroxy group of (E)-4-hydroxy-3,5-dimethoxybenzaldehyde oxime (2, C9H11NO4) have been protonated, giving birth to the organic salts [C7H8NO2]+·[Cl]− ([1H]+·[Cl]–) and [C9H12NO4]+·[Cl]− ([2H]+·[Cl]–). Results revealed that both salts display similar 1D “stair-like” ribbon models via the formation of intermolecular hydrogen bonding contacts between chloride ion and the protonated groups into four-membered squares. Note that the protonated acidic groups have shown much closer and stronger intermolecular interactions than the alkalic groups. In addition, 3D Hirshfeld surfaces, 2D fingerprint plots, and crystal void calculations have been performed, which have suggested 21.4% and 17.5% interactions around the protonated acidic and alkalic groups, respectively. This work will provide a n...

Background: Magnetic targeting, which utilizes a magnetic field to specifically deliver therapeutic agents to the targeted regions, can greatly improve the treatment efficiency. On the other hand, glucose-modified nanoparticles have also demonstrated good brain-targeting abilities. Fusion of both might further improve the brain targeting efficiency. Objective: To prepare, characterize and evaluate glucose-modified ibuprofen-loaded brain targeting magnetic nanoparticles (MNPs-APS-Glu). Methods: The magnetic nanoparticles MNPs-APS-Glu were designed and synthesized in order to effectively deliver ibuprofen to the brain through glucose transporter 1 (GLUT1) and an external magnetic field. The nanoparticles were characterized by FTIR, SEM and magnetic properties, and the drug loading capacity, cell cytotoxicity and drug release behavior of the new magnetic nanoparticles was studied. Results: The size of MNPs-APS-Glu was about 104.9 nm, and its drug loading capacity was up to 5%. Furthermore, these brain targeting magnetic nanoparticles maintained the magnetic property with a saturation magnetization level at ca. 32 emu/g and could release ibuprofen when incubated with various buffers, mice plasma and brain homogenate. Conclusions: The results indicated that the magnetic nanoparticles had potential to be a promising tool to selectively deliver drugs to the brain. This study may be conducive to the field of Central Nervous System (CNS) drugs delivery.

By using in-site generated formate, 2D HOFs of TCPP, with excellent stability and permanent porosity (BET surface area larger than 560 m2 g−1), have been obtained. The constructed 2D square-like TCPP-HCO2 grid sheets have shown considerable in-plane stability that comparable to the TCPP-based 2D MOFs, that can be exfoliated into atomically thin 2D nanosheets with efficient photocatalytic activity in aqueous system. These results are expected to shed light on the application-orientated one-pot synthesis for new kinds of multi-dimensional HOFs.

A novel [FeFe]-hydrogenase biomimetic catalyst [(μ-dmedt)Fe2(CO)5](μ-DPPF-O) (1) was prepared by CO-substitution in the (μ-dmedt)[Fe2(CO)6] complex with DPPF in THF. Confirmation of the catalyst structure was determined by FTIR, 1H NMR, 13C NMR, 31P NMR and single crystal X-ray diffraction. Complex 1 exhibited better catalytic reactivity for phenol hydroxylation than the all-carbonyl complex (μ-dmedt)[Fe2(CO)6]. The dihydroxybenzene selectivity of 94.0% and phenol conversion of 42.9% were obtained under the optimal reaction conditions. The relationships between electron density of the Fe Fe bond and the catalytic activity of these complexes were revealed, which showed that the more electron rich the Fe Fe bond is, the better catalytic hydroxylation activity was achieved.

The purpose of this study was to find heat-stable peptide biomarkers in cooked meats of five animal species: pork, chicken, duck, beef, and sheep. First, whole proteins and peptides were analyzed and identified by LC–MS to find homologous proteins and potential peptide biomarkers in the five different raw meats. Next, the peptide biomarkers of the raw and cooked meats were confirmed by multiple reaction monitoring (MRM). Thirty-four peptide biomarkers and twenty heat-stable peptide biomarkers were confirmed for the raw meats and the cooked meats, respectively. Eighteen of the heat-stable peptide biomarkers were not previously reported. Peptide biomarkers verified by MRM permit identification of each species with high specificity and selectivity to provide reliable results for meat authenticity after grilling and instant-boiling. Some of the biomarkers are species-specific only among the above five species.

A series of liposome ligands (Bio-Chol, Bio-Bio-Chol, tri-Bio-Chol and tetra-Bio-Chol) modified by different branched biotins that can recognize the SMVT receptors over-expressed in breast cancer cells were synthesized. And four liposomes (Bio-Lip, Bio-Bio-Lip, tri-Bio-Lip and tetra-Bio-Lip) modified by above mentioned ligands as well as the unmodified liposome (Lip) were prepared to study the targeting ability for breast cancer. The cytotoxicity study and apoptosis assay of paclitaxel-loaded liposomes showed that tri-Bio-Lip had the strongest anti-proliferative effect on breast cancer cells. The cellular uptake studies on mice breast cancer cells (4T1) and human breast cancer cells (MCF-7) indicated tri-Bio-Lip possessed the strongest internalization ability, which was 5.21 times of Lip, 2.60 times of Bio-Lip, 1.67 times of Bio-Bio-Lip and 1.17 times of tetra-Bio-Lip, respectively. Moreover, the 4T1 tumor-bearing BALB/c mice were used to evaluate the in vivo targeting ability. The data showed the enrichment of liposomes at tumor sites were tri-Bio-Lip > tetra-Bio-Lip > Bio-Bio-Lip > Bio-Lip > Lip, which were consistent with the results of in vitro targeting studies. In conclusion, increasing the density of targeting molecules on the surface of liposomes can effectively enhance the breast cancer targeting ability, and the branching structure and spatial distance of biotin residues may also have an important influence on the affinity to SMVT receptors. Therefore, tri-Bio-Lip could be a promising drug delivery system for targeting breast cancer.

The ionic liquid [BMIM][NTf2] was developed as an ideal medium in which Rh(III)-catalyzed directed C–H carbenoid coupling reactions can be conducted efficiently and sustainably. More significantly, the ionic liquid can not only achieve the recycle of catalyst system but also improve the efficiency of catalyst, presenting that carbenoid coupling reactions can be accomplished at room temperature within a short period of time. Thus, this work would be useful in expanding applications of C–H activation strategies as tools for assembling novel organic molecules.

A Cp*Rh(III)/IL-based direct C-H bond cyanation system was developed for the first time. The system is a mild, efficient, and recyclable method for the synthesis of aryl nitriles. Many different directing groups can be used in this cyanation, and the reaction tolerates a variety of functional groups.

D-glucaric acid is a promising platform compound used to synthesize many other value-added or commodity chemicals. The engineering of Escherichia coli for efficiently converting D -glucose to D-glucaric acid has been attempted for several years, with mixed sugar fermentation recently gaining growing interests due to the increased D-glucaric acid yield. Here, we co-expressed cscB, cscA, cscK, ino1, miox, udh, and suhB in E. coli BL21 (DE3), functionally constructing an unreported route from sucrose to D-glucaric acid. Further deletion of chromosomal zwf, pgi, ptsG, uxaC, gudD, over-expression of glk, and use of a D -fructose-dependent translation control system for pgi enabled the strain to use sucrose as the sole carbon source while achieving a high product titer and yield. The titer of D-glucaric acid in M9 medium containing 10 g/L sucrose reached ~1.42 g/L, with a yield of ~0.142 g/g on sucrose.

An efficient procedure for the synthesis of thiophosphates is described. Without using any metallic catalyst or base, the direct sulfur-phosphorus coupling reaction of disulfides and dialkyl trimethylsilyl phosphite (DTSP) was carried out under solvent-free reaction conditions in moderate to excellent yields with good functional group compatibility. The reaction conditions represent an advance over established methods not only in omitting the need for expensive catalysts or solvents, but also in shortening the reaction time significantly.These transformations are easy to conduct and can be readily applied to gram-scale preparation.

Tubular structure TiO2/C/TiO2 hybrids were successfully fabricated via impregnation-calcination method. A castoff of tubular structure FCT (the fluff of the chinar tree) was employed as template and carbon source, and economical TiCl4 was purchased as titanium source. In particular, the outer tube wall of the TiO2/C/TiO2 hybrid was constructed with interlaced and curly nanofibers. Nevertheless, the inner tube wall was assembled with spheroid-likely TiO2 nanoparticles. In addition, the graphitic carbon layer was formed between TiO2 nanofibers and nanoparticles. The FCT played a vital role in inducing and assembling the hierarchical tube structure of the TiO2/C/TiO2 hybrid. Furthermore, the design of the hydrolysis reaction during the preparation process also made contributions on building the unique structure. The hydrolysis reaction was taken place by blowing atmosphere, which could control the hydrolysis reaction at an appropriate reaction rate. Furthermore, the graphitic C layer in the TiO2/C/TiO2 hybrid could accelerate the migration and separation of the photogenerated electron during the reaction process. At appropriate carbon content, the TiO2/C/TiO2 could degrade 99% tetracycline hydrochloride (TH) under simulated sunlight irradiation within 30 min.

To probe the influence of phosphine ligand substitution on the well-known [2Fe2S] model, two new [FeFe]-hydrogenase model complexes with the phosphine ligands, PMe3 or P(CH3O)3, were synthesized, such as μ-(SCH(CH2CH3)CH2S)–Fe2(CO)5PMe3 1, and μ-(SCH(CH2CH3)CH2S)–Fe2(CO)5P(CH3O)3 2 Confirmation of structures was provided by FTIR, 1H NMR, 13C NMR, 31P NMR, elemental analyses and single-crystal X-ray analysis. The crystal structure of complex 2 shows that the P(CH3O)3 ligand has less steric effect on the coordination geometry of the Fe atom than the PMe3 ligand. In the presence of HOAc in CH3CN solution, the hydrogen evolution overpotentials of complexes 1 and 2 were 0.91 V and 0.81 V, respectively. Comparatively, complex 2 produces hydrogen at an overpotential of 0.1 V, lower than that for complex 1. A further electrocatalytic study showed the maximum charges for 1 and 2 were 31.3 mC and 56.3 mC at −2.30 V for 10 min, respectively. These studies showed that the complexes 1 and 2 have the ability, as novel electrocatalysts, for catalysis of hydrogen production, and complex 2 has better electrocatalytic ability than complex 1.

A novel and efficient method for the total synthesis of the natural product decumbenine B was described. The shortcomings in the existing synthetic routes of this isoquinoline alkaloid were minimized through the application of Ru(III)-catalyzed direct ortho-hydroxymethylation of intermediate 9. With this method, decumbenine B could be easily synthesized from commercially available materials by only five steps with an overall yield of 26.1%.

Ibuprofen is one of the most potent non-steroid anti-inflammatory drugs (NSAIDs) and plays an important role in the treatment of neurodegenerative diseases. However, its poor brain penetration and serious side effects at therapeutic doses, has hindered its further application. Thus, it is of great interest to develop a carrier-mediated transporter (CMT) system that is capable of more efficiently delivering ibuprofen into the brain at smaller doses to treat neurodegenerative diseases. In this study, a dual-mediated ibuprofen prodrug modified by glucose (Glu) and vitamin C (Vc) for central nervous system (CNS) drug delivery was designed and synthesized in order to effectively deliver ibuprofen to brain. Ibuprofen could be released from the prepared prodrugs when incubated with various buffers, mice plasma and brain homogenate. Also, the prodrug showed superior neuroprotective effect in vitro and in vivo than ibuprofen. Our results suggest that chemical modification of therapeutics with warheads of glucose and Vc represents a promising and efficient strategy for the development of brain-targeting prodrugs by utilizing the endogenous transportation mechanism of the warheads.

A practical synthesis of CHF2-substituted 3-azabicyclo[3.1.0]hexanes was developed for the first time. The key step was photochemical decomposition of CHF2-substituted pyrazolines. This protocol has the advantages of simple operation, and mild conditions, as well as excellent functional group tolerance, giving the desired products in moderate to excellent yields.

A novel efficient method for the synthesis of thiophosphate derivatives catalyzed by methylene blue with blue light irradiation under an air atmosphere is described. The thiophosphate products, which are found in many pharmaceuticals and pesticides, were obtained in moderate to good yields. Moreover, Stern–Volmer fluorescence quenching experiments were conducted on reaction partners, demonstrating that the transformation involves photoinduced electron transfer. A plausible mechanism is proposed.

Efficient palladium-catalyzed C–H ethoxycarbonylation of 2-aryl-1,2,3-triazoles was developed by using diethyl azodicarboxylate as the esterification reagent. A wide variety of aryl esters containing 1,2,3-triazoles were obtained in moderate to good yields. In addition, density functional theory calculations were used to enhance the mechanistic studies.

Blending is a convenient method to regulate the crystallization behavior and thus the performance of polymer materials, but poor compatibility in crystalline phase for different components remarkably depresses the co-crystallization capability, which poses a great challenge to effective regulation of the properties for crystalline/crystalline blends. In this work, the co-crystallization between two kinds of polyester with similar chain structure, poly(butylene succinate) (PBS) and poly(butylene fumarate) (PBF) is investigated and found to be dependent on the blending ratio and crystallization condition. A new type of co-crystal is only discovered in the PBS-rich blends (i.e., PBS/PBF-6/4 and PBS/PBF-8/2), and, further, it is proved as the isomorphism between PBS and PBF by employing various characterizations of differential scanning calorimeter and Fourier transformation infrared spectrometer and X-ray diffractometer. Both the enhancing cooling rate and the increasing PBS content benefit the growth of isomorphic co-crystal, and, its fraction in the blend of PBS/PBF-8/2 can reach as high as ∼75% during a fast cooling rate of 40 °C/min. In addition, the changes of Gibbs free energy for including butylene fumarate unit into PBS-type crystal and including butylene succinate unit into PBF-type crystal are respectively calculated as −0.96 and 1.94 kJ/mol, revealing the intrinsic thermodynamic driving force for the forming of isomorphism and clarifying why isomorphism only occurs in the PBS-rich blends. Finally, a summary of the crystallization behavior of PBS/PBF blend is reasonably sketched, which will help design the crystalline/crystalline blends with desired structure and performance.

Venlafaxine, a novel third generation antidepressant drug, has been described as a reference treatment for major depression in clinical, owing to its ability of inhibiting both noradrenalin and serotonin neuronal reuptake, and inhibiting dopamine reuptake slightly. However, its clinical application is hampered by a limited brain distribution. Glucosylation is an effective way to enhance the brain targeting ability of drugs, but the bidirectional transport of glucose transporter 1 (GLUT1) might decrease the concentrations of venlafaxine-glucose (V-G) in brain before the release of parent drug venlafaxine. To conquer this drawback of GLUT1, “lock-in” thiamine disulfide system (TDS) was introduced to modify the V-G conjugate. Both conjugates could release venlafaxine when incubated with the various buffers, mice plasma and brain homogenate. The evaluation in vivo demonstrated that venlafaxine-TDS-glucose (V-TDS-G) had an improved targeting ability and significantly increased the level of venlafaxine in brain compared to the naked venlafaxine and V-G. The relative uptake efficiency (RE) and concentration efficiency (CE) were enhanced to 5.69 and 5.70 times higher than that of naked venlafaxine, respectively. The results of this study suggest that the conjugate strategy based on the glucose-TDS (G-TDS) is available to enhance the delivery of central nervous system (CNS) drugs into brain. This article is protected by copyright. All rights reserved.

Inspired by natural [Fe]-hydrogenase, mono-iron complex Fe II (CO) 3 I 3 -[trimethylpyridine-H] (complex 1 ) was synthesized and characterized by IR, 1 H NMR, 13 C NMR, EA. The singe crystal structure of the complex 1 was characterized by single crystal X-ray diffraction. The hydroxylation reaction of phenol to dihydroxybenzene was conducted using complex 1 as catalyst in aqueous phase at ambient temperature. Under the optimum conditions, the phenol conversion was 20.5%, dihydroxybenzene selectivity was 83.7%, catechol/hydroquinone (mol/mol) was 2.6. Complex 1 can be a promising catalyst for hydroxylation of phenol to dihydroxybenzene because of mild reaction conditions and good catalytic performance.

Hierarchical micro/nanostructured tubular TiO 2 were prepared by impregnation-calcination method with FCT (the fluff of the chinar tree) as biological template and titanium tetrachloride as precursor. The resultant samples possess curly tubular structure and the exterior outline of the samples look like fried dough twist. Moreover, the wall of the tube is assembled with spherical-likely nanoparticles. Apparently in the process of preparation, the FCT played pivotal roles as substrate and inducer for assembling the curly tubular structure of micro/nanostructured TiO 2 . Furthermore, the micro/nanostructured TiO 2 have abundant pore structures and large surface area, which are beneficial to the improvement of photocatalytic activity. Under UV light irradiation, the as-prepared TiO 2 exhibits nearly 100% photocatalytic decolorization rate in 30 min and 90% TOC (total organic carbon) degradation rate in 60 min for dye methyl orange (MO).

μ-(SCH(CH2CH3)CH2S)-Fe2(CO)4(κ2-DPPE) (complex 1, DPPE is 1,2-bis (diphenylphosphor) ethane), which can be regarded as a model of the [FeFe]‑hydrogenase active site, was synthesized and characterized. The reversible isomerization of complex 1 under N2 and CO atmosphere was demonstrated by cyclic voltammetry, IR spectroscopy and 31P NMR. Furthermore, we discovered that both the presence of a CO atmosphere and the addition of H2O can independently trigger the same inversion of configuration of complex 1. The electrocatalytic proton reduction capacity of 1 was evaluated under varying conditions. It was found that addition of a little H2O to CH3CN can facilitate its efficiency of electrocatalytic proton reduction. The possible mechanism of transition between axial/basal and dibasal isomers and the function of H2O in the electrocatalytic reaction are discussed. Keywords: Hydrogenase, Reversible isomerization, Proton reduction, Water-promoted, Catalytic efficiency

Synthesis of 3-aryloxy-2-oxindole derivatives from 3-hydroxy-2-oxindoles and aryl boronic acids through copper(II)-promoted reaction is achieved. This reaction provides an efficient protocol for the coupling between aryl boronic acid and tertiary aliphatic alcohol, opening a new avenue to format corresponding 3-phenyl-3-aryloxy-2-oxindole core, which has potentially value in the field of life-science.

Rivaroxaban is an oral direct Factor Xa inhibitor to treat thrombus. The aim of this study is to investigate the drug–excipient compatibility between rivaroxaban tablet and pharmaceutical excipients by a combination of thermal and spectroscopic methods. Differential scanning calorimetry (DSC) is the most important technique to evaluate the compatibility. In addition, X-ray powder diffraction (XRPD) is a complementary technique to explain the DSC result and exclude relevant interaction. On the basis of DSC curves about rivaroxaban and excipient and mixture (1:1, w/w), the rivaroxaban was considered to be compatible with the most excipients (microcrystalline cellulose, lactose, hydroxyl propyl methyl cellulose, magnesium stearate). Meanwhile, the XRPD studies also showed the compatibility of rivaroxaban and pharmaceutical excipients, especially for the sodium lauryl sulfate. Overall, the compatibility of the excipients with rivaroxaban was assessed successfully by DSC and XRPD, and the formulations developed using the compatible excipient were found to be stable.

The introduction of a new metabolic pathway will affect the host’s other metabolic pathways. Differential metabolomics is a useful method to reveal the relationship between the different metabolic pathways inside a microorganism. Three Klebsiella pneumoniae strains with different 1-butanol production capability were chosen to study the differential metabolomics to reveal the relationship between 1-butanol synthesis and other metabolic pathways. The biosynthesis of Val, Leu, Ile, Met, Gly and Ala were all found to have close relationships with the 1-butanol synthesis. To tuning the synthesis of these amino acids, CRISPRi (Clustered regularly interspaced short palindromic repeats interference) system was adopted. The resulting transcription levels, intracellular amino acid content, and 1-butanol production were significantly affected. In comparison with KLA, the concentrations of intracellular Ile, Leu, Val, Met, and Ala in all the repressed strains was reduced, and the resulting content of intracellular Thr and 1-butanol production was increased. The largest increase in 1-butanol production was obtained with the strain KLA-ilvB3 with a yield increase 154% higher than that of KLA. The results show that CRISPRi is a feasible method to manipulate genes in Klebsiella pneumoniae.