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Background: Benzoxazine is one of the most important privileged scaffolds in medicinal chemistry. Compounds bearing benzoxazine moiety usually have a variety of biological activities, such as anti-inflammatory, anti-microbial, anti-tuberculosis, anti-oxidant and anti-cancer activities. The fascinating bioactivity profile of benzoxazine scaffold in various fields has prompted medicinal chemists to design and discover novel benzoxazine derivatives as potential therapeutic candidates with the desired biological properties. Objective: This review aimed to provide a comprehensive elucidation on the recent advances of benzoxazine derivatives in medicinal chemistry. Method: We have searched the recent literatures about benzoxazine derivatives from the online resources and databases, such as pubmed, scifinder and google scholar. Conclusion: Benzoxazine is a versatile structure and building block in medicinal chemistry. Benzoxazine derivatives have gained considerable attention from medicinal chemists due to their various pharmacological properties and multiple modification sites. This review might help medicinal chemists to seek for new drug candidates with better bioactivities and pharmacokinetics properties.

New physical insights and a robust approach are provided to develop super-MIEC anodes for high-rate batteries, which would bridge two materials families—nanoporous framework materials and conductive oxides.

Density functional theory calculations of Nazarov cyclizations showed that 3-alkenyl-2-indolylmethanol and tryptophol formed binary and ternary complexes, respectively, in the presence and absence of H2O to produce C–N and C–C products.

Phosphanylnaphtho[2,1-d]oxazoles, a P,N-chelating ligand, were synthesized through one-pot phosphonation/Cu-catalyzed oxidative condensation, followed by methylation and reduction.

Background At present, the clinical conclusion that robotic-assisted thoracic surgery (RATS) and video-assisted thoracic surgery (VATS), which is better for patients with non-small cell lung cancer (NSCLC) is not clear. Therefore, this meta-analysis aimed to compare the perioperative outcomes between RATS and VATS for NSCLC. Methods The Population, Interventions, Comparators, Outcomes, and Study design (PICOS) framework was employed to develop the search strategy, and the findings was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We searched EMbase, The Cochrane Library, PubMed, Web of Science, CNKI, and Wan Fang Data to collect clinical studies about RATS vs. VATS for patients with NSCLC from inception to October 2019. The following outcomes were measured: rate of conversion to thoracotomy, postoperative complications, postoperative hospital mortality, lymph node dissection, hospitalization time, operating time, and postoperative drainage days. Estimation of potential publication bias was conducted by Begg’s test and Egger’s test. The Standardized Mean Difference (SMD) and Odds Ratio (OR) with 95% confidence intervals (CI) were pooled using Stata 15.0 software. Results A total of 18 studies involving 60,349 patients were included. Among them, 8,726 cases were in the RATS group, and 51,623 were in the VATS group. The results of meta-analysis showed that the operation time of RATS group was longer than that of VATS group (SMD=0.532, 95% CI: 0.391–0.674, P=0.000). And the further meta-analysis suggested that the incidence of postoperative complications was lower in patients who underwent RATS after 2015 (OR=0.848, 95% CI: 0.748–0.962, P=0.010). Meanwhile, there was no significant difference between both groups in postoperative hospitalization time (SMD=0.003, 95% CI: −0.104–0.110, P=0.957). In addition, more lymph nodes were retrieved in RATS group than VATS (SMD=0.308, 95% CI: 0.131–0.486, P=0.001). However, the conversion rate, retrieved lymph node station, days to tube removal and in-hospital mortality rate have no significant differences between both groups. Discussion The current meta-analysis indicates that the perioperative outcomes of RATS and VATS for NSCLC are equivalence. Due to the limited quantity and quality of included studies, the above conclusions still need to be verified by more high-quality studies.

Nitrogen dioxide (NO

Zirconium is a silvery-white malleable and ductile metal at room temperature with a crustal abundance of 162 ppm. Its compounds, showing Lewis acidic behavior and high catalytic performance, have been recognized as a relatively cheap, low-toxicity, stable, green, and efficient catalysts for various important organic transformations. Commercially available inorganic zirconium chloride was widely applied as a catalyst to accelerate amination, Michael addition, and oxidation reactions. Well-designed zirconocene perfluorosulfonates can be applied in allylation, acylation, esterification, etc. N-Chelating oganozirconium complexes accelerate polymerization, hydroaminoalkylation, and CO

A series of 6H-benzimidazo[1,2-c][1,3]benzoxazin-6-one derivatives were synthesized in moderate to good yield by reaction of 2-(1H-benzimidazol-2-yl)phenols with triphosgene, and the structures of the target compounds were characterized by NMR, IR, and HRMS methods. The fungicidal activity of the compounds was evaluated at 50 μg/ml concentration, and unsubstituted 6H-benzimidazo-[1,2-c][1,3]benzoxazin-6-one showed 75.1% activity against Sclerotinia sclerotium, which was higher than that of chlorothalonil.

Developing new oxide solid electrolytes with fast Li-ion transport and high stability is an important step to realize high-performance solid-state Li-ion batteries. Hydrates materials containing confined water widely exist in nature or can be easily synthesized. However, they have seldom been explored as Li solid electrolytes due to the stereotype that the presence of water limits the electrochemical stability window of a solid electrolyte. In this work, we demonstrate that confined water can enhance Li-ion transport while not compromising the stability window of solid electrolytes using Li-H-Ti-O quaternary compounds as an example system. Three Li-H-Ti-O quaternary compounds containing different amounts of confined water were synthesized, and their ionic conductivity and electrochemical stability are compared. The compound contains nano-confined pseudo-water is demonstrated to have an ionic conductivity that is 2~3 order of magnitude higher than the water-free Li4Ti5O12 and similar stability window. A solid-state battery is made with this new compound as the solid electrolyte, and good rate and cycling performance are achieved, which demonstrates the promise of using such confined-water-containing compounds as Li-ion solid electrolytes. The knowledge and insights gained in this work open a new direction for designing solid electrolytes for future solid-state Li-ion batteries. Broadly, by confining water into solid crystal structures, new design freedoms for tailing the properties of ceramic materials are introduced, which creates new opportunities in designing novel materials to address critical problems in various engineering fields.

High-volumetric-energy-density lithium-ion batteries require anode material with a suitable redox potential, a small surface area, and facile kinetics at both single-particle and electrode level. Here a family of coarse-grained molybdenum substituted titanium niobium oxides Mo[subscript x]Ti[subscript 1−x]Nb[subscript 2]O[subscript 7+y] (single crystals with 1~2 μm size) underwent hydrogen reduction treatment to improve electronic conduction was synthesized, which is able to stably deliver a capacity of 158.5 mAh g[superscript −1] at 6,000 mA g[superscript −1] (65.2 % retention with respect to its capacity at 100 mA g[superscript −1] ) and 175 mAh g[superscript −1] (73 % capacity retention over 500 cycles) at 2,000 mA g[superscript −1], respectively. Via careful in situ electrochemical characterizations, we identified the kinetic bottleneck that limits their high-rate applications to be mainly ohmic loss at the electrode level (which mostly concerns electron transport in the composite electrodes) rather than non-ohmic loss (which mostly concerns Li+ lattice diffusion within individual particles). Such a kinetic problem was efficiently relieved by simple treatments of Mo substitution and gas-phase reduction, which enable full cells with high electrode density, and high volumetric energy/power densities. Our work highlights the importance of diagnosis, so that modifications could be made specifically to improve full-cell performance.

Silicon (Si) has recently aroused great interest as a promising anode material for lithium-ion batteries with high energy density due to its high theoretical capacity. However, the application of Si remains a great challenge owing to its extremely large volume change during cycling, thus resulting in dramatic capacity fading. Herein, a novel structure design of the porous Si/C composite with Si nanoparticles embedded in the carbon nanosheets has been successfully achieved by using a recrystallized NaCl template with appropriate particle size. The outermost sheet-like carbon coating can improve the electronic conductivity and contribute to the formation of a more stable solid-electrolyte interphase layer, while the inner void space effectively buffers the volume expansion of Si during the lithiation process. In addition, only a structure with Si particles anchored on the surface of carbon nanosheets has been obtained by using a commercial NaCl template with large particle size, confirming the effective regulation of the NaCl template in the microstructure and thus the electrochemical properties of the Si/C composites. As expected, benefiting from the combination of the outermost carbon coating and recrystallized NaCl-derived porous structure, the as-obtained Si/C composite demonstrates attractive cycling stability and rate performance as an anode material for lithium-ion batteries.

Aqueous Zn-ion batteries (ZIBs) have garnered significant attention regarding the growing demand for electrical energy, owing to their decent electrochemical performance, operational safety, low cost and environmental friendliness. However, optimization of cathode materials is still an issue and opportunity facing aqueous ZIBs. Organic coating is a common strategy to modify other types of cathode materials through the synergistic effect. Here, we synthesized a series of ultrafine Mn3O4/polypyrrole core–shell nanodot composites (Mn3O4/PPy) through an in situ polymerization strategy. The PPy content in this core–shell structure was continuously tuned by adjusting the pyrrole addition during self-polymerization. An optimized Mn3O4/PPy core–shell cathode with a PPy ratio of 14.6 wt% delivers a high capacity (332.5 mA h g−1 at 0.1 A g−1) and excellent rate performance (141.7 mA h g−1 at 1 A g−1). More importantly, Mn3O4/PPy shows superior long-term cycling stability over 1500 cycles (with a high capacity retention of 92.5% at 1.0 A g−1), which is almost three times longer than that of pristine Mn3O4 nanodots. We have clarified that the improvement in long-term cycling stability is attributed to the increased electron/ion conductivity, alleviated Mn2+ dissolution and enhanced structural stability caused by PPy coating.

High amounts of glutathione in tumour cells are able to decrease the effectiveness of cancer treatments by capturing the therapeutically necessary reactive oxygen species during the photodynamic therapy (PDT) process. In addition, many photosensitizers for PDT are limited by the light tissue penetration depth, which hinders the application of these compounds to treat deep seated or large tumors. To overcome the aforementioned drawbacks, herein, the use of a mitochondrial-targeting iridium(III) prodrug Ir–B(OH)2 which is responsive to the tumour microenvironment (H2O2 rich) and able to release two-photon photosensitizers (Ir–OH) for PDT and methylquinone as a glutathione scavenger for disrupting the mitochondrial redox homeostasis is presented. Based on the reduction of glutathione, the cancerous cells were more vulnerable to oxidative stress caused by two-photon photodynamic therapy. Upon two-photon laser irradiation (730 nm), a strong and amplified phototoxic effect towards human gastric adenocarcinoma (AGS) cellular and animal models was observed.

Synthesis of novel N-aryl-N′-(2-hydroxybenzyl)ethylenediamine derivatives by reduction of N-arylaminoacetamides is presented in this paper. Fungicidal activity of the products is tested, and one of those exhibits 94.1% inhibitory activity against Gibberella zeae at the concentration of 50 μg/mL. The fungicidal activity of the compounds was enhanced with the increase of their log P.

Background The associations between circulating tumor cells (CTCs) in peripheral blood and prognosis of patients with esophageal carcinoma (EC) have been investigated by a number of studies, but the results are not consistent. Therefore, this study aimed to explore this controversial subject. Methods A literature database search was performed according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. The risk ratio (RR), hazard ratio (HR) and their 95% confidence intervals (CIs) were retained as the effect measures. If necessary, subgroup analyses and metaregression should also be performed to clarify the heterogeneity. Results Thirty-three studies, containing 3,236 patients with EC, were included in this meta-analysis. The results showed that overall survival (OS) (HR =2.14; 95% CI, 1.73-2.65) and progression-free survival (PFS) (HR =2.29; 95% CI, 1.69-3.11) were worse in CTCs-positive patients. CTC positivity is also significantly associated with depth of infiltration (RR =1.42; 95% CI, 1.10-1.82, P=0.21) and tumor-node-metastasis (TNM) stage (RR =1.36; 95% CI, 1.09-1.69, P=0.22). However, there was no significant relationship between CTC-positive and distant metastasis (RR =1.58; 95% CI, 1.00-2.50, P=0.65). Conclusions Detection of CTCs had prognostic value for EC patients. Positive CTC is associated with poor prognosis and some prognostic factors, such as depth of infiltration and TNM stage, but not related to metastasis.

Isoquinolines constitute an important class of natural alkaloids, that demonstrate a wide range of biological activities. Therefore, development of new methods for efficient synthesis of isoquinoline and its derivatives has attracted considerable attention of chemists and pharmacologists over recent years. In this review the progress of isoquinoline synthesis that provides creative inspiration and expands novel ideas for researchers in this field is summarized.

Small-molecule photosensitizers have great application prospects in photoelectrochemical (PEC) sensing due to their defined composition, diversified structure, and adjustable photophysical properties. Herein, we propose a new strategy for PEC analysis based on the target-induced in situ formation of the organic photosensitizer. Taking thiophenol (PhSH) as a model analyte, we designed and synthesized a 2,4-dinitrophenyl (DNP)-caged coumarin precursor (Dye-PhSH), which was then covalently coupled onto the TiO

Multilayer three-dimensional (3D) chiral molecules have potential application in luminescent material fields, but the mechanism of their AIE effect is not clear. In this work, the theoretical mechanism of the aggregation-induced emission (AIE) effect has been studied for three 3D molecules of 2-X-1,3-bis(8-(4-Y-phenyl)naphthalen-1-yl)-1,3-dihydrobenzo[d][1,3,2] diazapho-sphole-2-oxie (A. X = NH2, Y = H; B. X = i-Pr, Y = H; C. X = NH2, Y = OMe). The geometrical structures and spectral properties in solution, crystal and aggregation are discussed using the combined approach of molecular dynamics (MD), DFT/TD-DFT and ONIOM QM/MM calculations. The S0 and S1 structural changes of 3D molecules show that the variation of the naphthalene and benzene rings is reduced in aggregation. Huang-Rhys (HR) factor and reorganisation energy are smaller in aggregation than in solution, especially in low-frequency vibration modes. It suggests that aggregation restricts the rotation of benzene and naphthalene rings and constrains the low-frequency vibration modes, which allows the radiated channel of the excited state molecule to be opened and glow when aggregated. This study provides an excellent explanation for the AIE phenomenon of 3D chiral molecules in experiments.

A novel ratiometric fluorescent fluoride probe based on isoquinolinium salts has been designed and synthesized. According to the qualitative and quantitative studies the chemosensor has high selectivity and sensitivity to fluoride. Fluoride induces deprotection of the silyl protecting group of the hydroxyl group and causes a significant change in emission wavelength. The relative fluorescent intensity (I435/I540) increases linearly with F– concentration in the range of 0–10.0 μmol/L. The dynamic determination process is monitored by 1H NMR spectroscopy.

Osteoarthritis (OA) is an age-related degenerative disease, which is characterized by chronic joint pain, inflammation and the damage of joint cartilage. At present, steroidal drugs and nonsteroidal anti-inflammatory drugs (NSAIDS), selective cyclooxygenase-2 (COX-2) inhibitors, are the first-line drugs for the treatment of OA. However, these drugs could lead to some cardiovascular side effects. Therefore, it is urgent to develop novel agents for the treatment of OA. Matrix metalloproteinase-13 (MMP-13), an important member of matrix metalloproteinases (MMPs) family, plays a vital role by degrading type II collagen in articular cartilage and bone in OA. It is noted that MMP-13 is specially expressed in the OA patients, and not in normal adults. In addition, broadspectrum MMP inhibitors could result in some painful and joint-stiffening side effects, called musculoskeletal syndrome (MSS) in the clinical trials. Thus, developing selective MMP-13 inhibitors is a potential strategy for the therapy of OA. In this review, we summarize the recent progress of selective MMP-13 inhibitors including two subfamilies, namely zinc-binding and non-zinc-binding selective MMP-13 inhibitors.