Abstract Redox‐active esters (RAEs) as active radical precursors have been extensively studied for C−B bond formations. However, the analogous transformations of stabilized radicals from the corresponding acid precursors remain challenging owing to the strong preference towards single‐electron oxidation to the stable carbocations. This work describes a general strategy for rapid access to various aliphatic and aromatic boronic esters by mild photoinduced decarboxylative borylation. Both aryl and alkyl radicals could be generated from the leaving group‐assisted N‐hydroxybenzimidoyl chloride esters, even α‐CF 3 substituted substrates could be activated for further elaboration.
To explore the relationship between estradiol (E2) and the incidence of hyperuricemia (HUA) in adult women and to explore whether glucolipid metabolism disorders play a mediating role in mediating this relationship.
Sulfonyl fluorides are key components in the fields of chemical biology, materials science and drug discovery. In this line, the highly active SO2F radical has been employed for the construction of sulfonyl fluorides, but the utilization of gaseous ClSO2F as radical precursor is limited due to the tedious and hazardous preparation. Meanwhile, the synthesis of sulfonyl fluorides from inert SO2F2 gas through a fluorosulfonyl radical (·SO2F) process has met with inevitable difficulties due to the high homolytic bond dissociation energy of the S(VI)-F bond. Here we report a radical fluorosulfonylation strategy for the stereoselective synthesis of alkenyl sulfonyl fluorides and functional alkyl sulfonyl fluorides with an air-stable crystalline benzimidazolium fluorosulfonate cationic salt reagent. This bench-stable redox-active reagent offers a useful and operational protocol for the radical fluorosulfonylation of unsaturated hydrocarbons with good yield and high stereoselectivity, which can be further transformed into valuable functional SO2F moieties.
Redox-active esters (RAEs) as active radical precursors have been extensively studied for C-B bond formations. However, the analogous transformations of stabilized radicals from the corresponding acid precursors remain challenging owing to the strong preference towards single-electron oxidation to the stable carbocations. This work describes a general strategy for rapid access to various aliphatic and aromatic boronic esters by mild photoinduced decarboxylative borylation. Both aryl and alkyl radicals could be generated from the leaving group-assisted N-hydroxybenzimidoyl chloride esters, even α-CF3 substituted substrates could be activated for further elaboration.
Background: Chronic stress is an important risk factor for depression. The nesfatin-1 (NES1)-oxytocin (OT)-proopiomelanocortin (POMC) neural pathway, which is involved in the stress response, was recently shown to have an anorectic effect in the hypothalamus. Our previous study showed that Xiaoyaosan, a well-known antidepressant used in traditional Chinese medicine, effectively relieved appetite loss induced by chronic immobilization stress (CIS). However, whether Xiaoyaosan ameliorates depression-like behaviors and anorexia by regulating the NES1-OT-POMC neural pathway remains unclear. Objective: To investigate whether the antidepressant-like and anti-anorexia effects of Xiaoyaosan are related to the NES1-OT-POMC neural pathway in the hypothalamus. Methods: Rats were randomly divided into control, CIS, Xiaoyaosan treatment, and fluoxetine treatment groups. The rats in the CIS, Xiaoyaosan treatment, and fluoxetine treatment groups were subjected to CIS for 21 consecutive days, during which they were administered distilled water, a Xiaoyaosan decoction [3.854 g/(kg·d)] or fluoxetine [1.76 mg/(kg·d)], respectively, by gavage, and their body weights and food intake were monitored daily. The rats were subsequently subjected to the open field test and sucrose preference test. Then, the expression levels of corticosterone and NES1 in the serum and the expression levels of NES1, OT, POMC, and melanocortin-4 receptor (MC4R) in the hypothalamus were determined by real-time fluorescence quantitative polymerase chain reaction, Western blot analysis, and immunochemistry. Furthermore, immunofluorescence double staining was used to determine whether related proteins in the hypothalamic NES1-OT-POMC neural pathway were co-expressed. Results: Compared to control rats, rats exposed to CIS exhibited gradually less food intake and lower body weights and significantly increased concentrations of NES1 in the serum and paraventricular nucleus. Moreover, the expression levels of POMC, OT, and MC4R in the hypothalamus were significantly higher in the CIS group than those in the control group. However, these changes were reversed by pretreatment with Xiaoyaosan and fluoxetine. Specifically, the expression levels of members of the NES1-OT-POMC neural pathway were lower in the Xiaoyaosan-treated group than in the CIS group. Conclusion: Xiaoyaosan ameliorates CIS-induced depression-like behaviors and anorexia by regulating the NES1-OT-POMC neural pathway in the hypothalamus.
Vinylboronates and alkylboronates are key components in variegated transformations in all aspects of chemical science. This work describes a sequential radical difunctionalization strategy for the construction of fluorine-containing vinylboronates and alkylboronates with the integrated redox-active reagent N-trifluoromethylthiophthalimide. This multifunctional N–S precursor offers a scalable and practical protocol for the trifluoromethylthiolation–borylation of unsaturated hydrocarbons in a highly regio- and stereoselective fashion, which can be further converted into valuable synthons via boryl migration.
Although the anxiolytic-like effects of Xiaoyaosan, a Chinese herbal formula, have been described in many previous studies, its underlying mechanism remains undefined. The cytokine tumour necrosis factor-\(\alpha\) (TNF-\(\alpha\)) and its closely associated janus kinase 2 (JAK2)-signal transducer and activator of transcription (STAT3) signalling pathway regulate the neuro-inflammatory response in the brain, thus participating in the development of anxiety. Our purpose was to investigate whether the anxiolytic-like effects of Xiaoyaosan are related to the TNF-\(\alpha\)/JAK2-STAT3 pathway in the hippocampus. We examined the effects of Xiaoyaosan on behaviours exhibited in the elevated plus maze test, open field test and novelty-suppressed feeding test as well as hippocampal neuron damage and changes in the TNF-\(\alpha\)/JAK2-STAT3 pathway in a rat model of chronic immobilization stress (CIS)-induced anxiety. Xiaoyaosan exerts anxiolytic-like effects on CIS-induced anxiety, with a significant alleviation of anxiety-like behaviours, an attenuation of hippocampal neuron damage, and a reversal of the activation of the TNF-\(\alpha\)/JAK2-STAT3 pathway in the hippocampus that are similar to the effects of the JAK2 antagonist AG490. However, Xiaoyaosan and AG490 failed to effectively regulate apoptosis-related factors, including Bax and Caspase-3. These results suggest that Xiaoyaosan attenuates stress-induced anxiety behaviours by down-regulating the TNF-\(\alpha\)/JAK2-STAT3 pathway in the rat hippocampus.
Cohesion is one of key factors influencing the performance of collaborative learning. But it is hart to reckon and assess it in online collaborative learning environments. Social network analysis (SNA) is a new method and technique analyzing the properties of the interaction relations between participants. In this paper, we introduced the related key concepts in SNA, and presented an analysis model which can analyze the cohesion of groups effectively and precisely, and then showed a case study which was from a quasi-experiment in our instruction practice, lastly, drew several useful principles on reckoning cohesion in online collaborative learning by SNA.
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