SuFEx click chemistry demonstrates remarkable molecular assembly capabilities. However, the effective utilization of alkyl sulfonyl fluoride hubs in SuFEx chemistry, particularly in reactions with alcohols and primary amines, presents considerable challenges. This study pioneers an intramolecular chalcogen bonding activated SuFEx (S-SuFEx) click chemistry employing alkyl sulfonyl fluorides with γ-S as the activating group. The ChB-activated alkyl sulfonyl fluorides can react smoothly with phenols, alcohols, and amines, exhibiting enhanced reactivity compared to SO2F2. Excellent yields have been achieved with all 75 tested substrates. Pioneering the application of S-SuFEx chemistry, we highlight its immense potential in organic-inorganic linking, considering the critical role of interfacial covalent bonding in material fabrication. The S-SuFEx hub 1c, incorporating a trialkoxy silane group has been specifically designed and synthesized for organic-inorganic linking. In a simple step, 1c efficiently anchors various organic compounds onto surfaces of inorganic materials, forming functionalized surfaces with properties such as antibacterial activity, hydrophobicity, and fluorescence.
The dynamic disulfide linkage plays a vital role in various biological processes as well as drugs and biomaterials. The conversion of thiols to their corresponding disulfides is a hallmark of sulfur chemistry, but notoriously difficult to control. Achieving optimal reactivity and selectivity continues to pose significant challenges. Here, we describe a click chemistry for disulfide formation from thiols in both batch and flow-mode using SO2F2, which display exceptional selectivity toward disulfide formation through an effective nucleophilic substitution cascade. This reaction’s unique characteristics satisfy the stringent click-criteria with its high thermodynamic driving force, straightforward conditions, wide scope, quantitative yields, exceptional chemoselectivity, and non-chromatographic purification process. The modular synthesis of symmetrical, unsymmetrical, cyclic and polydisulfides is demonstrated, along with the formation of disulfide cross-linked hydrogels.
In this study, 12 flavonoid glycosides were selected based on virtual screening and the literature, and Quercimeritrin was selected as the best selective inhibitor of α-glucosidase through in vitro enzyme activity inhibition experiments. Its IC50 value for α-glucosidase was 79.88 µM, and its IC50 value for α-amylase >250 µM. As such, it could be used as a new selective inhibitor of α-glucosidase. The selective inhibition mechanism of Quercimeritrin on the two starch-digesting enzymes was further explored, and it was confirmed that Quercimeritrin had a strong binding affinity for α-glucosidase and occupied the binding pocket of α-glucosidase through non-covalent binding. Subsequently, animal experiments demonstrated that Quercimeritrin can effectively control postprandial blood glucose in vivo, with the same inhibitory effect as acarbose but without side effects. Our results, therefore, provide insights into how flavone aglycones can be used to effectively control the rate of digestion to improve postprandial blood glucose levels.
The incorporation of antioxidants in food products is essential to prevent or delay deterioration, thereby addressing food spoilage. Thiol compounds, recognized for their natural antioxidant properties, are widely used in various foods; however, their antioxidant capacity is often limited. This study investigates the potential enhancement of thiol antioxidant capacity through the addition of a soluble, low-toxic inorganic Sm-cluster. Our findings demonstrate that the Sm-cluster significantly bolsters the antioxidant efficacy of thiol compounds. We explored, for the first time, the in vitro antioxidant activities of an Sm-oxo/hydroxy cluster combined with a cysteine derivative for potential food applications. The composition exhibited a robust inhibition of aromatic aldehyde flavor compound oxidation and displayed strong, dose-dependent DPPH (2,2-diphenyl-1-picrylhydrazine) radical scavenging activity. Notably, the antioxidant activity of the Sm-cluster/cysteine derivative was further enhanced under strong visible light conditions, which typically increased the likelihood of oxidation. These results suggest that the combination of inorganic cluster and thiol compounds presents a promising natural alternative to traditional antioxidants in the food industry.
Polyether amines are versatile compounds characterized by a flexible structure, consisting of polyoxypropylene and polyoxyethylene as the backbone, with amine groups at each end. They have widespread applications in various industrial processes and daily life. Despite their versatility, the utilization of polyether amines as base catalysts is rare. In this study, one kind of three-arm polyether amine 1 was employed as an environmentally friendly, cost-effective catalyst for the aerobic oxidation of thiophenols, leading to the synthesis of disulfides. The oxidative coupling of thiols serves as a fundamental pathway for the production of disulfides, which are vital in both chemical and biological processes. In contrast to known methods for thiol oxidation, this polyether amine-based catalytic process eliminates the need for expensive stoichiometric oxidants and minimizes the formation of over-oxidized by-products. Using a mere 0.5 mol % of the polyether amine 1 as the catalyst, a remarkable > 96% yield was achieved for all 16 tested substrates, encompassing a diverse range of functional groups, under the catalytic aerobic oxidation conditions. Furthermore, it is noteworthy that over 90% of the polyether amine catalyst can be efficiently recovered for reuse without loss of activity, making this a sustainable and cost-effective catalytic approach.