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In the presence of the Suginome reagent (PhMe2Si-Bpin), a large panel of electron-withdrawing alkenes was successfully converted into the hydrosilylated product in good to excellent yields. This direct electrochemical hydrosilylation does not require exogenous oxidants and catalysts. Preliminary mechanistic study supported the involvement of a silyl radical, which reacted on the alkene. [ABSTRACT FROM AUTHOR]

Aim An arteriovenous fistulae ( AVF) is the preferred vascular access for maintenance haemodialysis patients. Its dysfunction is often due to venous stenosis, which is mainly caused by neointimal hyperplasia. Additionally, haemodynamic forces, especially wall shear stress ( WSS), as a mechanical stimuli to venous wall have a significant role in neointimal hyperplasia. The purpose of this study was to evaluate the association between WSS and neointimal hyperplasia. Methods An 'end-to-side' AVF was created between the right femoral artery and vein of canines. Canines were killed at 7 and 28 days post-surgery. The velocity and WSS in the three-dimensional computational model of AVF were simulated using computational fluid dynamics ( CFDs). The four typical sites of the vein evaluated in this study, chosen according to the haemodynamic analysis, included the arteriovenous anastomosis ( A-V), the juxta-anastomotic segment ( J-V), the juxta-ligation segment ( L-V) and the proximal vein ( P-V). The specimens were haematoxylin-eosin stained and the intima-media thickening was then measured. Results Neointimal hyperplasia was more obvious in the inner wall of the J-V and L-V (low-and-disturbed WSS) sites compared with the P-V and A-V sites, and the outer wall of the L-V and J-V segments (high or laminar WSS) ( P < 0.01). Conclusion In this study, we described the haemodynamic condition in the AVF and found that neointimal hyperplasia predisposed to occur in the inner wall of venous segment near the anastomosis. We also found that not only the neointimal hyperplasia has a strong inverse correlation with WSS levels, but also is related to flow patterns. [ABSTRACT FROM AUTHOR]

In this paper a label-free fluorescent sensor for probing the interaction between heparin and protein was reported. Heparin, the bioactive polyanions, formed supramolecular assemblies with cationic surfactant cetyltrimethyl ammonium bromide (CTAB). The environment-dependent dye pyrene, encapsulated in hydrophobic interiors of the supramolecular assemblies worked as the fluorescence probe. Once the heparin-binding protein was added, competing interactions of protein with heparin would weaken the interaction between CTAB and heparin. As a result, the noncovalently sequestered pyrene would be released upon disassembly and the fluorescence of the released pyrene was subsequently decreased. The binding events were exemplified by protamine and Tat peptide, these processes were also verified by DLS and TEM. Such a strategy is appealing as organic synthesis was traded off against supramolecular assembly. This label-free fluorescent system is simple, selective, convenient, and can serve as a good complement to other existing methods, also this method has the potential for preprimary drug screening. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER), characterized by a four‐electron transfer kinetic process, represents a significant bottleneck in improving the efficiency of hydrogen production from water electrolysis. Consequently, extensive research efforts have been directed towards identifying single‐atom electrocatalysts with exceptional OER performance. Despite the comprehensive understanding of the OER mechanism, its application to other valuable synthetic reactions has been limited. Herein, we leverage the MOOH intermediate, a key species in the Mn−N−C single‐atom catalyst (Mn‐SA@NC), which can be cyclically delivered in the OER. We exploit this intermediate' s capability to facilitate electrophilic transfer with silane, enabling efficient silane oxidation under electrochemical conditions. The SAC electrocatalytic system exhibits remarkable performance with catalyst loadings as low as 600 ppm and an exceptional turnover number of 9132. Furthermore, the catalytic method demonstrates stability under a 10 mmol flow chemistry setup. By serving as an OER electrocatalyst, the Mn‐SA@NC drives the entire reaction, establishing a practical Mn SAC‐catalyzed organic electrosynthesis system. This synthesis approach not only presents a promising avenue for the utilization of electrocatalytic OER but also highlights the potential of SACs as an attractive platform for organic electrosynthesis investigations. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER), characterized by a four‐electron transfer kinetic process, represents a significant bottleneck in improving the efficiency of hydrogen production from water electrolysis. Consequently, extensive research efforts have been directed towards identifying single‐atom electrocatalysts with exceptional OER performance. Despite the comprehensive understanding of the OER mechanism, its application to other valuable synthetic reactions has been limited. Herein, we leverage the MOOH intermediate, a key species in the Mn−N−C single‐atom catalyst (Mn‐SA@NC), which can be cyclically delivered in the OER. We exploit this intermediate' s capability to facilitate electrophilic transfer with silane, enabling efficient silane oxidation under electrochemical conditions. The SAC electrocatalytic system exhibits remarkable performance with catalyst loadings as low as 600 ppm and an exceptional turnover number of 9132. Furthermore, the catalytic method demonstrates stability under a 10 mmol flow chemistry setup. By serving as an OER electrocatalyst, the Mn‐SA@NC drives the entire reaction, establishing a practical Mn SAC‐catalyzed organic electrosynthesis system. This synthesis approach not only presents a promising avenue for the utilization of electrocatalytic OER but also highlights the potential of SACs as an attractive platform for organic electrosynthesis investigations. [ABSTRACT FROM AUTHOR]

The cover page of the "Chinese Journal of Chemistry" is presented.

Starch has been widely explored in food additives such as thickeners, stabilizers, and gelling agents due to its excellent properties. However, the poor dispersion and emulsification of starch limit direct applications. To overcome this challenge, starch is extracted from potatoes and etherified to carboxymethyl starch sodium (CMS) to form a cold water soluble starch, which is prepared as an amphiphilic colloid by esterification with lauric acid using Novozym 435 catalyst. As a result of the new groups introduced and concomitant changes produced in the granule structure, carboxymethyl starch sodium laurate starch (CMS‐LS) typically shows strong emulsifying properties, low surface tension, and good amphiphilic properties. Characterizations by Fourier transform infrared (FTIR), Scanning Electron microscope (SEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS) show that CMS‐LS is successfully prepared. The results of water solubility, surface tension, contact angle measurement, and emulsification test indicate that CMS‐LS is an excellent emulsifier, amphiphilic polymer and surfactant. Therefore, CMS‐LS is successfully synthesized and esterified, which can be widely used in food, cosmetics, and biomedicine fields. [ABSTRACT FROM AUTHOR]