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Dipyrrin and BODIPY molecules can bind tightly to TiO2 surfaces when lacking substituents in the 3,5 positions. This offers a new strategy for anchoring molecules onto surfaces with a simple synthesis and ultrafast electron injection.

Thiazolidinedione, an important heterocyclic ring system, is a pharmacophore and a privileged scaffold in medicinal chemistry. Researchers have shown its potential application as a backbone for inhibitors, as it is involved in anticancer development strategies, cancer progression and metastasis. In this paper, the anticancer activities of thiazolidinedione derivatives were reviewed for the first time with respect to different substituents and their positions. This work may imitate a stirring wheel to guide further advanced development of new anticancer molecules with high efficacy.

Electrocatalytic ammonia oxidation at room temperature and pressure allows energy-economical and environmentally friendly production of nitrites and nitrates. Few molecular catalysts, however, have been developed for this six- or eight-electron oxidation process. We now report [Cu(bipyalk)]

Hybrid photoanodes for water-splitting photoelectrochemical cells (WS-PECs) consist of a visible-light-absorbing semiconductor (VLASC) with a molecular water-oxidation catalyst (mWOC) attached and ...

The extension of reticular chemistry concepts to electrically conductive three-dimensional metal–organic frameworks (MOFs) has been challenging, particularly for cases in which strong interactions between electroactive linkers create the charge transport pathways. Here, we report the successful replacement of tetrathiafulvalene (TTF) with a nickel glyoximate core in a family of isostructural conductive MOFs with Mn2+, Zn2+, and Cd2+. Different coordination environments of the framework metals lead to variations in the linker stacking geometries and optical properties. Single-crystal conductivity data are consistent with charge transport along the linker stacking direction, with conductivity values only slightly lower than those reported for the analogous TTF materials. These results serve as a case study demonstrating how reticular chemistry design principles can be extended to conductive frameworks with significant intermolecular contacts., U.S. Department of Energy, Basic Energy Sciences (Grant DE-SC0018235)

Background/aims The expression of transcription factor Zbtb1 is essential for the maintenance and development of various blood cells in the hematopoietic system. In the current study, we found that the total number of thymocytes in PLZF deficient mice was reduced compared with thymocytes in wild-type mice, and the number of early T-cell progenitors decreased. However, the decrease of thymocytes in PLZF deficient mice was not cell intrinsic. This study adds new information regarding the regulation of the PLZF gene in the development and self-renewal of T cells. Methods The thymus was isolated from newborn mice, and the two lobes of each thymus were physically separated. Each host received a thymus, two lobes, each placed at one end of the kidney, as described in the literature. Tail vein blood was periodically collected from some of the recipients and analyzed for the presence of peripheral blood T cells. Results In PLZF-EGFP reporter mice and neonatal thymus transplantation to the kidney, we found that PLZF was highly expressed in DN1 (Lineage-CD44+CD25-) cells of thymic grafts of Rag2/γc-/- recipient mice. We found that the proportion of PLZF wild-type and mutant-derived cells in the thymocytes of recipient mice after bone marrow transplantation is approximately equal to the competitive bone marrow chimeric mouse model, and all mice contain a normal thymus. Conclusion The development of T cells suggests that the effect of the PLZF gene on T cell differentiation and development is not cell intrinsic. However, in the neonatal mouse thymic transplant model in the Rag2/γc-/- recipient mouse, deletion of the PLZF gene results in a significant decrease in the proportion of DN1 cells from the donor in the thymic graft.

A series of novel 1,4-benzodioxan derivatives containing Schiff base are synthesized by the method of splicing active substructures. All compounds are assayed for antimicrobial activity. The preliminary results indicate that most of the products demonstrate higher antibacterial activity against Gram-negative bacteria strains than Gram-positive bacteria strains. Compounds 4d and 4m exhibit better antibacterial activity against E. coli (MIC = 0.78 and 0.17 μg/mL), respectively; compound 4g displays better antibacterial activity against P. aeruginosa (MIC = 0.78 μg/mL). Eleven common antibacterial targets are selected for molecular docking of target compounds. The results demonstrate that all target compounds have the strongest binding energy to Tyrosine-tRNA synthetase (-CDOCKER_INTERACTION_ENERGY, kcal/mol: 47.1486 and 47.3776). Therefore, it is speculated that the target compounds can be used as novel tyrosine-tRNA synthetase inhibitors.

Thiazolidinedione (TZD) is a novel peroxides proliferator activated receptor γ (PPARγ) agonist with many side effects. Herein, we developed a series of novel TZD analogues as partial agonists targeting PPARγ. The study of anti-hyperglycemic activity and anti-inflammatory activity enabled us to identify a novel compound, 4 g, which quickly recover the blood glucose of mice at the concentration of 100 mg/kg, and show similar anti-inflammatory activity to ibuprofen at the concentration of 20 mg/kg. The competitive binding assay confirmed direct binding of 4 g to the LBD of PPARγ with IC50 being 1790 nM, and dose-dependently increased the transcriptional activity of PPARγ. Besides, through computer-aided drug design software simulation docking, it was found that compound 4 g showed the best binding ability to target protein PPARγ. Furthermore, because of the introduction of benzene containing group at N3 position, the stability of H12 in the active pocket is reduced and the stability of H3 and β-fold is increased, showing the characteristics of some PPARγ agonists, based on the docking model analysis. Together, these results suggest that 4 g is a promising PPARγ agonist that deserves further investigation.

A series of diacylhydrazine derivatives containing 1,4-benzodioxan 1-17 has been designed, synthesized and evaluated for antitumor activity. Most of the synthesized compounds demonstrated potent antitumor activity and low toxicity. Compound 10 demonstrated the most potent biological activity against MCF-7 cancer cell line, which was comparable with the positive control 5-fluorouracil. Docking simulation by positioning compound 10 into the MetAP2 structure active site was performed to explore the possible binding model.

Licorice is a traditional Chinese medicine, which is often used as sweetener and cosmetic ingredients in food and pharmaceutical industries. Among them, glycyrrhetic acid is one of the most important agents. Studies have shown that glycyrrhetic acid exhibited antitumor activities as PPARγ agonist. However, the limited number of PPARγ glycyrrhetinic agonists and their high toxicity greatly limit the design based on the structure. Therefore, clarifying the binding mode between PPARγ and small molecules, we focused on the introduction of a natural active piperazine skeleton in the position of glycyrrhetinic acid C-3. According to the Combination Principle and the Structure-Based Drug Design, 19 glycyrrhetic acid derivatives were designed and synthesized as potential PPARγ agonists. Compounds 4c and 4q were screened as high-efficiency and low-toxicity lead compounds.

A series of novel 1,4-benzodioxane thiazolidinedione piperazine derivatives targeting FabH were designed and synthesized. The compounds exhibited better inhibitory activity against Gram-negative bacteria by computer-assisted screening, antibacterial activity test and E. coli FabH inhibitory activity test, wherein compound 6j exhibited the most significant inhibitory activity (MIC = 1.80 μΜ for P. aeruginosa, MIC = 1.56 μΜ for E. coli). Besides, compound 6j still showed the best E. coli FabH inhibitory activity (IC50 = 0.06 μΜ). Moreover, the antibacterial activities of all compounds were strongly correlated with the inhibitory ability of FabH, with a correlation coefficient of 0.954. Computational docking studies also showed that compound 6j has interacting with FabH key residues in the active site.

The joint of the donor and acceptor moieties allows a facile and effective strategy to develop novel organic conjugated materials. However, few pieces of work report the understanding of the donor-acceptor interactions at the molecular level. Herein, we developed three small molecules containing one acceptor motif with different amounts of the donor unit. By combining theoretical calculations and energy level characterization, the lowest unoccupied molecular orbital (LUMO) levels of the three molecules were proven to be almost identical. The molecular packing modes were evaluated from crystal structure prediction. Owing to the donor-acceptor interactions, the packing mode can be tuned from a 1D slipped stacking to a 2D brick layer. The 2D molecular packing and charge transport channel endowed the materials a higher electron mobility of 3.29 cm2 V-1 s-1 in the single-crystal field-effect transistors after such modulation.

The detailed relationship between film morphology and the performance of solution processed n-type organic thermoelectric (TE) devices is investigated. It is interesting to find that the better ordered molecular packing of n-type polymer can be achieved by adding a small fraction of dopant molecules, which is not observed before. The better ordered structure will be favorable for the charge carrier mobility. Meanwhile, dopant molecules improve free carrier concentration via doping reaction. As a result, a significantly enhanced electrical conductivity (12 S cm(-1)) and power factor (25.5 μW m(-1) K(-2)) of TE devices are obtained. Furthermore, the phase separation of conjugated polymer/dopants is observed for the first time with resonant soft X-ray scattering. Our results indicate that the miscibility of conjugated polymers and dopants plays an important role on controlling the morphology and doping efficiency of TE devices.

Wafer-scale fabrication of high-performance uniform organic electronic materials is of great challenge and has rarely been realized before. Previous large-scale fabrication methods always lead to different layer thickness and thereby poor film and device uniformity. Herein, the first demonstration of 4 in. wafer-scale, uniform, and high-performance n-type polymer monolayer films is reported, enabled by controlling the multi-level self-assembly process of conjugated polymers in solution. Since the self-assembly process happened in solution, the uniform 2D polymer monolayers can be facilely deposited on various substrates, and theoretically without size limitations. Polymer monolayer transistors exhibit high electron mobilities of up to 1.88 cm2 V-1 s-1 , which is among the highest in n-type monolayer organic transistors. This method allows to easily fabricate n-type conjugated polymers with wafer-scale, high uniformity, low contact resistance, and excellent transistor performance (better than the traditional spin-coating method). This work provides an effective strategy to prepare large-scale and uniform 2D polymer monolayers, which could enable the application of conjugated polymers for wafer-scale sophisticated electronics.

Recent progress in the development of small molecular skeleton-derived polo-like kinase (PLK1) catalytic domain (KD) inhibitors has led to the synthesis of multiple ligands with high binding affinity. However, few systematic analyses have been conducted to identify key PLK1-PBD domain and characterize their interactions with potent PLK1 inhibitors. Therefore, we designed a series of PLK1-PBD inhibitors with an in silico scaffold modification strategy. A docking simulation combined with a primary screen in vitro were performed to filter for the lead compound, which was then substituted, synthesized and evaluated by a variety of bioassays. The biological profile of 4v suggests that this compound may be developed as a potential anticancer agent.

A series of vanillin derivatives have been designed and synthesized and their biological activities were also evaluated as potential inhibitors of FtsZ. These compounds were assayed for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. Compounds with potent antibacterial activities were tested for their FtsZ inhibitory activity. Compound 4u showed the most potent antibacterial activity with MIC of 0.28 μg/mL against E. coli strains and exhibited the most potent FtsZ inhibitory activity with polymerization IC50 of 2.1 μM. Docking simulation was performed to position compound 4u into the FtsZ active site to determine the probable binding conformation.

Whether selection of chip removal air volume is reasonable or not, do affect the performance of blasthole drill and bit’s life. How to calculate air volume always make the designers confused. In this paper, writer use theory of gas-solid two-phase flow and energy principle combined with characteristic of rock ballasts from the mine site to determine particle rising speed, free floating speed and air flow rate of the rock ballasts. And according to the relation between particle and particle group’s floating speed calculate floating speed and the corresponding chip removal air volume among different diameter of particle of the same minerals. It can provide a method of calculation to designer, which is very reference value to for the practical application.

C17H12ClN3O4, monoclinic, P21/c (no. 14), a = 6.8425(7) Å, b = 14.1931(16) Å, c = 17.0132(17) Å, β = 101.044(3)°, V = 1621.1(3) Å3, Z = 4, R gt(F) = 0.0522, wR ref(F 2) = 0.1171, T = 296 K.

[(18)F] fluorodeoxyglucose-positron emission tomography (FDG-PET) is regarded as a unique imaging modality, because the images reflect tumor activity. This characteristic of PET encouraged us to use it to develop a novel method of quantitatively measuring liver metastasis viability.F344 rats were injected with rat colon adenocarcinoma cells (RCN-9 cell line) via the portal vein, and some of them were treated with 5-fluorouracil (5-FU). Tumor growth and tumor activity were measured by PET. We used a tumor viability index (TVI) to evaluate changes in tumor activity and to quantitatively evaluate tumor proliferation activity, instead of using the standardized uptake value (SUV) of the tumor tissue. The TVI was compared with the number of tumor nodules and the proliferating cell nuclear antigen (PCNA) index 28 days after RCN-9 cell inoculation.[(18)F] FDG uptake by the liver tumors was measured by PET, and the TVI was found to increase as the tumor nodules increased in number and size. The TVI values in the experimental model represented the viability of tumors suppressed by chemotherapy, and the values were significantly correlated with the number of nodules and the PCNA index.The TVI was concluded to be superior to the SUV, the commonly used indicator, for evaluating tumor growth, especially that of multiple, small tumors.

p- or n-Dopants have played significant roles in the improvement of organic electronic devices through the controllable doping of organic semiconductors. However, there has been little study of air-stable n-dopants under ambient conditions with strong doping capability due to the low electron affinities of organic semiconductors. Herein, a 1,4-dihydropyridine-based derivative is designed and facilely synthesized as an efficient n-dopant. The doping process is systematically investigated by UV–vis–NIR spectroscopy in solution and ultraviolet photoelectron spectroscopy in the solid state. Excellent conductivities are obtained for a variety of doped n-type semiconductors via a simple solution process without further treatment, suggesting a broad class of 1,4-dihydropyridine derivatives could be used as n-dopants in future organic electronic devices.

We prepared a liver metastatic tumor model by injection of rat colon adenocarcinoma cells to Fischer F344 rats through portal vein, and applied positron emission tomography (PET) using 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) ([18F]FDG-PET) to this model. At an early stage of the model, multiple small tumor nodules appeared in the inferior lobes of the livers, and extended later into the superior lobes. To evaluate the tumor growth and tumor viability at the early stage, we proposed a new concept, tumor viability index (TVI), instead of the standardized uptake value (SUV) of the [18F]FDG uptake. The TVI was defined by subtracting the signal based on the normal liver from the total signal in the whole liver including tumor nodules: (whole liver SUV — normal liver SUV) × ml of whole liver region of interest (ROI). For the signal of the whole liver, ROIs were placed on six slices covering the whole liver, and the ROI of normal liver region was located in the superior lobe of the liver. The average TVI values increased with tumor growth and significantly correlated with the numbers of tumor nodules. The new concept may be useful for evaluating the tumor viability non-invasively and quantitatively by [18F]FDG-PET.