Synthesis and electrochemical performanceof cobalt disulfide

The anode material cobalt disulfide for lithium-ion batteries was synthesized using the hydrothermal method at a lower temperature. The microstructure and surface morphology of the powders were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrochemical tests showed that this sample had superior electrochemical properties. The first discharge capacity is up to 1313.9 mAh/g in the voltage range of 3.00–0.02 V at a current density of 50 mA/g. Adjusting the voltage range to 3.00–0.50 V, the first discharge capacity decreases, but the 20th discharge capacity is 435.5 mAh/g, which is better than what has been reported in the literature.     

An efficient, one-pot synthesis of trithiocarbonates from the corresponding thiols using the Mitsunobu reagent

A novel Mitsunobu-based protocol has been developed for the synthesis of a variety of symmetrical and unsymmetrical trithiocarbonates from primary, secondary and tertiary thiols using carbon disulfide, in good to excellent yields. This protocol is mild and efficient compared to other reported methods.     

Efficient synthesis of N,N′-dialkyl-N″-dialkylaminocarbothioyl thioureas from cyclic secondary amines, CS2, and N,N′-dialkyl carbodiimides in water

A mild, convenient, and practical one-pot procedure for direct synthesis of N,N′-dialkyl-N″-dialkylaminocarbothioyl thioureas is described via three-component reaction of cyclic secondary amines, CS₂, and N,N′-dialkyl carbodiimides in water at room temperature.     

邻-(N-芳酰基-N-甲氨基苯)-二硫化合物的合成：通过N-甲基-2-单芳基苯并噻唑啉在溶剂中的自发偶联反应和它们的血管内皮生长因子抑制活性

N-甲基-2-单芳基苯并噻唑啉 (1) 在固体状态时可以稳定地储藏在空气中。但是,它们在不同溶剂中却表现出了不同的行为。在醇溶液或二甲亚砜-水的体系中,1相对稳定;而在其它有机溶剂如：丙酮,氯仿,二氯甲烷和乙酸乙酯等溶剂中,会发生自发偶联反应生成相应的邻-(N-芳酰基-N-甲氨基苯)-二硫化合物 (2)。对这些新的化合物 (1) 和 (2) 进行了体外人乳腺癌细胞 (MDA-MB-231) 血管内皮生长因子靶点筛选,大部分化合物都表现出了抑制活性。实验结果表明这两类化合物 (1) 和 (2) 作为血管内皮生长因子抑制剂值得进行深入研究。     

Disulfide bond creates a small connecting loop in aminoxy peptide backbone

Disulfide-bond formation between the side chains of cysteine-cysteine pairs is often critical to the folding behavior, stability, and functionality of proteins. In this paper, we report that sulfur atoms can be introduced into the amide groups of aminoxy peptides to form a novel type of disulfide bridge, which creates a connecting loop in the peptide backbone.     

Azodicarboxylate-Mediated Peptide Cyclisation: Application to Disulfide Bond Formation in Solution and Solid Phase

Cyclic peptides are important molecules, playing key roles in protein architecture, as chemical probes, and increasingly as crucial structural elements of clinically-useful therapeutics. Herein we report methodology using azodicarboxylates as efficient reagents for the facile synthesis of cyclic peptides through a disulfide bridge. The utility of this approach in both solution and solid-phase, and compatibility with common amino acid side chain functionalities is demonstrated, resulting in cyclic peptides in good yield and purity. This approach has significant potential application for synthesis of molecules of biological or therapeutic significance.     

Fabrication of a novel electrochemical sensor based on tin disulfide/multi-walled carbon nanotunbes-modified electrode for rutin determination in natural vegetation

A tin disulfide and multi-walled carbon nanotube (SnS₂/CNTs) electrochemical sensor was constructed for the sensitive and selective determination of rutin in plants. Tin disulfide nanoflowers with various particle sizes were prepared by controlling the reaction time and composited with multi-walled CNTs. The morphology, crystal structure, and chemical composition of these SnS₂/CNTs composites were characterized using XRD, XPS, and SEM-EDS. Results illustrated that the SnS₂/CNTs had a large specific surface area, good conductivity, and remarkable electrocatalytic performance. The pH of the buffer solution, the scanning rate, and the amount of modified material were also optimized for the rapid detection of rutin. A 2-electron-2-proton mechanism, involving a few rapid and consecutive stages, was speculated to occur during rutin oxidation, based on the observed slope of -53 mV/pH. There was an appreciable linear relationship between the reductive peak current from DPV and the rutin concentration, ranging from 0.005-0.05 µmol/L and 0.1-6 µmol/L, with a detection limit of 0.22 nmol/L (S/N = 3). The sensor also demonstrated good selectivity, excellent sensitivity, and reproducibility when analyzing rutin in real plant samples, with satisfactory recovery, and was also highly consistent with results of HPLC, and thus could be used to evaluate the medicinal value of natural vegetation.     

Site‐Selective Disulfide Modification of Proteins: Expanding Diversity beyond the Proteome

The synthetic transformation of polypeptides with molecular accuracy holds great promise for providing functional and structural diversity beyond the proteome. Consequently, the last decade has seen an exponential growth of site‐directed chemistry to install additional features into peptides and proteins even inside living cells. The disulfide rebridging strategy has emerged as a powerful tool for site‐selective modifications since most proteins contain disulfide bonds. In this Review, we present the chemical design, advantages and limitations of the disulfide rebridging reagents, while summarizing their relevance for synthetic customization of functional protein bioconjugates, as well as the resultant impact and advancement for biomedical applications.