Latest ArticlesThe co-crystallization of quercetin (Qur) with a flexible molecule 4-(4-pyridinyldisulfanyl) pyridine (DPDS) in different solvents and conditions was investigated, yielded five multi-component crystalline phases and characterized with X-ray diffractions and thermal analysis. Although the crystal system of Qur-DPDS-MeOH and Qur-DPDS-Dioxane is the same, the desolvation results revealed that Qur-DPDS-MeOH transformed to Qur-DPDS when MeOH solvent molecules escape from the lattice, while Qur-DPDS-Dioxane transformed to Qur-DPDS-Ⅱ through a similar process, which is same with Qur-DPDS-THF. These two cocrystal polymorphs Qur-DPDS and Qur-DPDS-Ⅱ obey an enantiotropic relationship. Moreover, the formation of cocrystal solvates improves the packing efficiency of crystals. Crystal structure analysis showed that hydrogen bonds and conformations of the corresponding parent molecules play a major role in molecular assembly and crystal packing patterns, thus bring different physicochemical properties. Finally, the fluorescence spectra and quantum-chemical calculations were carried out to explore the difference in the optical-physical properties.
Trifluoromethylation/sulfonylation of alkynes from trifluoromethyl thianthrenium triflate and sulfur dioxide under extremely mild reaction conditions provides a facile access to trifluoromethyl-substituted vinyl sulfonohydrazides in moderate to good yields. This multicomponent reaction of trifluoromethyl thianthrenium triflate, alkynes, sulfur dioxide and hydrazines proceeds efficiently under visible light irradiation in the presence of photocatalyst at room temperature with broad substrate scope and excellent functional group compatibility. This reaction is highly stereoselective, and only (E)-isomers are obtained. Additionally, these trifluoromethyl-substituted vinyl sulfonohydrazides are further evaluated for anti-bacteria activity. In vitro activities of these compounds against Staphylococcus aureus (G+) and Escherichia coli (G−) are examined.
Cardiovascular disease (CVD) is a global health problem and is thought to be responsible for almost half of all deaths in the world. Nevertheless, currently available diagnostic methods for CVD are strongly depended on clinical observation and monitoring, which commonly result in false diagnosis. Herein, an attractive strategy of a metal-organic framework (MOF) nanofilm-based laser desorption/ionization mass spectrometry (LDI-MS) was developed for enhancing serum metabolic profiling, which could provide precise diagnosis and molecular subtyping of CVD. The porous MOF nanofilm fabricated on indium-tin oxide (ITO) glass possessed enhanced ionization efficiency and size-exclusion effect, which endowed it as substrate with high sensitivity and selectivity for serum metabolites. Furthermore, the MOF nanofilm with uniform surface and high orientation provided high-quality and high-reproducibility serum metabolic profiles (SMPs) without any tedious pretreatment. Further analysis of extracted serum metabolic fingerprints could successfully distinguish patients with CVD from healthy controls and also differentiate two major subtypes of CVD. This work not only extends the application of MOF nanofilm as an attractive MS probe, but also provide an alternative way for precise diagnosis of CVD in molecular level.
As a monoatomic bridge, fluoride ion can transmit efficient magnetic interaction between lanthanide ions but its effect on tuning the magnetization dynamics has not been well understood. Herein, two monofluoride-bridged dinuclear dysprosium complexes [Dy2F(bbpen)2(EtOH)2]Br·EtOH (1) and [Dy2F(bbppy)2]Br·2EtOH (2) with Dy-F-Dy angles of ~178° and their diamagnetic-ion diluted analogues 1´ and 2´ were synthesized. Magnetic studies reveal that 1 and 1´ barely show any magnetization dynamics, but 2 and 2´ exhibit strong magnetization dynamics. Systematical experimental analysis combined with ab initio calculations reveals that the different magnetization dynamics between 1 and 2 mainly originate from the effect of magnetic anisotropy by terminal ligand and bridging group of the chelating ligand, and the fluoride bridge can effectively suppress the quantum tunneling of the magnetization and turn on Orbach process in 2.
Levofloxacin (LVFX) as a representative drug of quinolone antibiotics is widely used in clinical, and its residues enriched in water bodies and sideline products seriously damage human health. It is imperative to develop a real-time/on-site sensing method for monitoring residual antibiotics. Here, we report a portable sensing platform by utilizing a composite fluorescent nanoprobe constructed by the cerium ions (Ce3+) coordination functionalized CdTe quantum dots (QDs) for the visual and quantitative detection of LVFX residues. This fluorescent probe provides a distinct color variation from red to green, which shows a good linear relationship to LVFX residues concentrations in the range of 0-6.0 µmol/L with a sensitive limit of detection (LOD) of 16.3 nmol/L. The smartphone platform with Color Analyzer App installed, which could accomplish quantified detection of LVFX in water, milk, and raw pork with a LOD of 27.9 nmol/L. The facile sensing method we proposed realizes rapid visualization of antibiotics residual in the environment and provides a practical application pathway in food safety and human health.
In the context of the circular economy, the huge amounts of biomass waste should be converted into value-added materials and energy to diminish pollution, atmospheric CO2 levels and costly waste disposal. Biological imaging usually uses expensive and toxic chemicals e.g., organic dyes, semiconductor quantum dots, calling for safer, greener, cheaper fluorescent probes for biological imaging in vitro and in vivo. In these regards, carbon quantum dots (CQDs)-based fluorescent probes using biomass waste as a precursor may have much higher potential. Here we transformed the biomass waste of peach leaves into value-added fluorescent CQDs through a low-cost and green one-step hydrothermal process. The obtained CQDs show excitation-dependent photoluminescence properties with a fluorescence lifetime of 5.96 ns and a quantum yield of 7.71% without any passivation. In addition, the CQDs have a fine size of 1.9 nm with good hydrophilicity and high fluorescent stability over pH 4.0–11.0 range. Fluorescence imaging of in vitro cell cultures and in vivo with zebrafish show that CQDs possess ultra-low toxicity and remarkable performance for biological imaging. Even when CQDs present at a concentration as high as 500 µg/mL, the organism can still maintain more than 90% activity both in vitro and in vivo, and present bright fluorescence. The cheaper, greener, ultra-low toxicity CQDs developed in this work is a potential candidate for biological imaging in vitro and in vivo.
Atmospheric pollutants can deteriorate air quality and put human health at risk. There is a growing need for green, economical, and efficient technologies, among which catalytic elimination technology is the most promising, to remove atmospheric pollutants. Two-dimensional transition metal oxides (2D TMOs) have recently become attractive catalysts due to their highly exposed active sites, excellent reactant transport properties, and extraordinary catalytic performance. This review systematically summarizes the top-down and bottom-up preparation methods of 2D TMOs and focuses on the specific applications of 2D TMOs in the catalytic elimination of atmospheric inorganic pollutants and volatile organic pollutants. The development of 2D TMOs in the catalytic elimination of atmospheric pollutants is prospected. This review is expected to provide design insights into efficient 2D TMOs to remove atmospheric pollutants.
Due to its difficulty and complexity, the cleavage and subsequent functionalization of the C(sp3)-C(sp3) single bond has received less attention than the CC bond formation reactions that have been extensively studied. Herein, by utilizing Cu/g-C3N4 nanometric semiconductor as a recyclable photocatalyst, an aerobic oxidative CC bond cleavage of aldehydes was developed with the promotion of amines under visible light irradiation. Based on the reaction, phenylacetaldehyde was selected as a highly efficient formylation reagent for amines. Under blue light irradiation, good to excellent yields of formamides were achieved for various amines in 1 atm oxygen atmosphere at room temperature. This methodology offers a practical, neutral and gentle alternative to the preparation of formamides.
The lantern-shaped cage Pd2L4 and tweezer-like PdL2 can be synthesized from the trans- and cis-isomer of an azobenzene-containing ligand, respectively, which were characterized by 1H, 13C, 1H-1H COSY, DOSY NMR spectroscopies, high-resolution ESI-MS and density function theory (DFT) calculations. The interconversion of Pd2L4 and PdL2 can be achieved via the cis-trans isomerization of the azobenzene unit on the ligand upon alternative irradiation of light 365 nm or 420 nm.
Benzo[b]thiophene fused compounds with a unique active heterocyclic skeleton have wide applications in the fields of medicinal chemistry, organic synthesis, and organic functional materials, which resulted in rapid development of many efficient methods for the construction of benzo[b]thiophene-fused heterocycles in recent years. Among these methods, the domino reaction of benzo[b]thiophene derivatives is a practical and powerful synthetic route to access benzo[b]thiophene-fused heterocycles by virtue of the particularity of sulfur atom. This review summarizes the latest developments in the construction of benzo[b]thiophene-fused heterocycles by ring formation at the C2-C3-position of benzo[b]thiophene derivatives in the past decade. Additionally, this review is divided into four parts according to the four kinds of benzo[b]thiophene derivatives used, including thioaurone, thioisatin, substituted benzo[b]thiophene, and azadiene.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
