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The transition metal‐catalyzed multi‐component cross‐electrophile sulfonylation, which incorporates SO2 as a linker within organic frameworks, has proven to be a powerful, efficient, and cost‐effective means of synthesizing challenging alkyl–alkyl sulfones. Transition metal catalysts play a crucial role in this method by transferring electrons from reductants to electrophilic organohalides, thereby causing undesirable side reactions such as homocoupling, protodehalogenation, β‐hydride elimination, etc. It is worth noting that tertiary alkyl halides have rarely been demonstrated to be compatible with current methods owing to various undesired side reactions. In this work, a zinc‐promoted cross‐electrophile sulfonylation is developed through a radical‐polar crossover pathway. This approach enables the synthesis of various alkyl–alkyl sulfones, including 1°‐1°, 2°‐1°, 3°‐1°, 2°‐2°, and 3°‐2° types, from inexpensive and readily available alkyl halides. Various functional groups are well tolerated in the work, resulting in yields of up to 93%. Additionally, this protocol has been successfully applied to intramolecular sulfonylation and homo‐sulfonylation reactions. The insights gained from this work shall be useful for the further development of cross‐electrophile sulfonylation to access alkyl–alkyl sulfones. [ABSTRACT FROM AUTHOR]

Introduction: Walnut green husk (WGH) is a waste byproduct from walnut industry. However, it is not well-known about its bioactive effect on human gut health., Methods: This study conducted in vitro digestion and fermentation experiments to study the bioactive effect of WGH., Results: Microbial fermentation was the primary mechanism to efficiently release phenolics and flavonoids, resulting in more excellent antioxidant capacities (DPPH, ABTS, and FRAP assays), which reached a highest value with 14.82 ± 0.01 mg VcE/g DW, 3.47 ± 0.01 mmol TE/g DW, and 0.96 ± 0.07 mmol FeSO 4 ·7H 2 O/g DW, respectively. The surface microstructure of WGH became loose and fragmented after microbial fermentation. The analytical results of gut microbiota demonstrated that WGH could significantly increase the relative abundance of Proteobacteria in phylum level and Phascolarctobacterium in genus level while certain pro-inflammatory bacteria (such as Clostridium_sensu_stricto_1, Dorea , Alistipes , and Bilophila ) was inhibited. Additionally, 1,373 differential metabolites were identified and enriched in 283 KEGG pathways. Of which some metabolites were significantly upregulated including ferulic acid, chlorogenic acid, umbelliferone, scopolin, muricholic acid, and so forth., Discussion: These results indicated that WGH could have antioxidant and anti-inflammatory activities in the human gut, which could improve the economical value of WGH in the food industry., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Ying, Wang, Wang, Li, Gu, Liu, Li, Liu, Xin and Wen.)

A novel fiber laser structure, to the best of our knowledge, based on an erbium-doped fiber ring (EDFR) and a silica microbottle resonator (MBR) is proposed and investigated experimentally. Two fiber laser samples based on MBRs with different geometries and diameters of 200 and 150 µm are fabricated, and their performance is studied experimentally. Periodic whispering gallery mode spectra of the MBRs are dependent on the position of the fiber taper used for coupling of light into the MBR, and this dependence is explored to achieve lasing at different wavelengths by moving the light coupling point along the axis of the microbottle incorporated into the proposed EDFR-MBR system. The influences of the pump laser power and light polarization on the system performance and laser stability are also investigated. Single-mode lasing with a maximum optical signal-to-noise ratio of 32 dB is demonstrated.