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The control of noncarbon stereogenic centers is of profound importance owing to their enormous interest in bioactive compounds and chiral catalyst or ligand design for enantioselective synthesis. Despite various elegant approaches have been achieved for construction of S‐, P‐, Si‐ and B‐stereocenters over the past decades, the catalyst‐controlled strategies to govern the formation of N‐stereogenic compounds have garnered less attention. Here, we disclose the first organocatalytic approach for efficient access to a wide range of nitrogen‐stereogenic compounds through a desymmetrization approach. Intriguingly, the pro‐chiral remote diols, which are previously not well addressed with enantiocontrol, are well differentiated by potent chiral carbene‐bound acyl azolium intermediates. Preliminary studies shed insights on the critical importance of the ionic hydrogen bond (IHB) formed between the dimer aggregate of diols to afford the chiral N‐oxide products that feature a tetrahedral nitrogen as the sole stereogenic element with good yields and excellent enantioselectivities. Notably, the chiral N‐oxide products could offer an attractive strategy for chiral ligand design and discovery of potential antibacterial agrochemicals. [ABSTRACT FROM AUTHOR]

Prussian blue analogues (PBAs) are recognized as promising cathode materials for sodium‐ion batteries (SIBs) due to their facile synthesis, low‐cost, high capacity, and environmental friendliness. However, high water content (>10 wt%) in the framework and unsatisfactory structural stability of PBAs are still the bottlenecks for industrial applications. Herein, interstitial K‐doping is employed to minimize the interstitial water and enhance the structural stability of Na2‐xFeMn[Fe(CN)6] (FeMnPBA), thereby boosting the sodium storage performance. The 3% K‐doping (K‐FeMnPBA3) demonstrates a much‐reduced water content of 6.9%, accompanied by a notably enhanced capacity of 139.1 mAh g−1 at 100 mA g−1 and a remarkable capacity retention of 77.1% after 700 cycles. Furthermore, the K‐FeMnPBA3/hard carbon (HC) pouch cell achieves a stable cyclability with 82.6% capacity retention after 600 cycles. This research offers valuable insights into low‐water PBAs for practical applications in SIBs. [ABSTRACT FROM AUTHOR]

A series of novel thiazine derivatives featuring axial chirality in both (R) and (S) configurations were successfully synthesized by N‐heterocyclic carbene (NHC)‐catalyzed enantioselective [3 + 3] annulations, and their potential as anti‐plant virus agents against potato virus Y (PVY) was evaluated. Biological activity results demonstrated that most of these chiral thiazine derivatives exhibited significant activities against PVY. Notably, compound (S)‐3g displayed a remarkable 58% inactivation effect against PVY at a concentration of 500 μg/mL, slightly surpassing the effectiveness of Ningnanmycin (NNM) at 57%. Additionally, (S)‐3g exhibited curative activity of 57%, which is superior to NNM (53%). Molecular docking studies revealed preliminary insights into the distinct biological properties of the two different enantiomers, (R) or (S)‐3g against PVY, wherein single enantiomer (S)‐3g formed a more stable interaction with PVY‐CP, as indicated by its lower binding free energy (−41.18 kcal/mol) compared to (R)‐3g (−36.9 kcal/mol). The findings in this study with a new class of axially chiral thiazine derivatives shall inspire further development of chiral heterocycles as potential drug candidates for the protection of plant virus infections. [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is an autoimmune disease mediated by anti-acetylcholine receptor (AChR) antibodies and dependent on CD4 positive T lymphocytes (CD4+T) cells. MicroRNA (miRNA) is an endogenous small single-stranded non-coding RNA that involved in post-transcriptional regulation and plays an important role in differentiation and function of CD4+T cells. Increasing evidences have shown that changes of miRNAs happened in MG patients, which may participate in the occurrence and development of MG by regulating CD4+T cells, and miRNA may be a potential therapeutic target for MG. In this paper, relationship between miRNA and MG was reviewed in order to provide new ideas for further research on the pathogenesis and clinical diagnosis and treatment of MG. [ABSTRACT FROM AUTHOR]

Developing methods to directly transform C(sp3) −H bonds is crucial in synthetic chemistry due to their prevalence in various organic compounds. While conventional protocols have largely relied on transition metal catalysis, recent advancements in organocatalysis, particularly with radical NHC catalysis have sparked interest in the direct functionalization of “inert” C(sp3) −H bonds for cross C−C coupling with carbonyl moieties. This strategy involves selective cleavage of C(sp3) −H bonds to generate key carbon radicals, often achieved via hydrogen atom transfer (HAT) processes. By leveraging the bond dissociation energy (BDE) and polarity effects, HAT enables the rapid functionalization of diverse C(sp3)−H substrates, such as ethers, amines, and alkanes. This mini‐review summarizes the progress in carbene organocatalytic functionalization of inert C(sp3)−H bonds enabled by HAT processes, categorizing them into two sections: 1) C−H functionalization involving acyl azolium intermediates; and 2) functionalization of C−H bonds via reductive Breslow intermediates. [ABSTRACT FROM AUTHOR]

The control of noncarbon stereogenic centers is of profound importance owing to their enormous interest in bioactive compounds and chiral catalyst or ligand design for enantioselective synthesis. Despite various elegant approaches have been achieved for construction of S-, P-, Si- and B-stereocenters over the past decades, the catalyst-controlled strategies to govern the formation of N-stereogenic compounds have garnered less attention. Here, we disclose the first organocatalytic approach for efficient access to a wide range of nitrogen-stereogenic compounds through a desymmetrization approach. Intriguingly, the pro-chiral remote diols, which are previously not well addressed with enantiocontrol, are well differentiated by potent chiral carbene-bound acyl azolium intermediates. Preliminary studies shed insights on the critical importance of the ionic hydrogen bond (IHB) formed between the dimer aggregate of diols to afford the chiral N-oxide products that feature a tetrahedral nitrogen as the sole stereogenic element with good yields and excellent enantioselectivities. Notably, the chiral N-oxide products could offer an attractive strategy for chiral ligand design and discovery of potential antibacterial agrochemicals., (© 2024 Wiley-VCH GmbH.)

Background: Plant fungal diseases pose a significant threat to crop production. The extensive use of chemical pesticides has led to growing environmental safety risks and pesticide resistance of various plant pathogens. Therefore, it is an urgent task to explore novel eco-friendly fungicidal agents with high efficacy to combat fungal infection., Results: In this study, we rationally designed a series of novel thymol derivatives by incorporation of the sulfonamide moiety and evaluated their biological activities against plant pathogenic fungi. The bioassay results underscored the remarkable in vitro antifungal activity of compounds 5m and 5t against Phytophthora capsici (P. capsici), with EC 50 values of 8.420 and 8.414 μg/mL, respectively. Their efficacies were superior to that of widely used commercial fungicides azoxystrobin (AZO, 20.649 μg/mL) and cabendazim (CAB, 251.625 μg/mL). Furthermore, compound 5v exhibited excellent in vitro antifungal activity against Sclerotinia sclerotiorum (S. sclerotiorum), with an EC 50 value of 12.829 μg/mL, significantly outperforming AZO (63.629 μg/mL). In vivo bioassays demonstrated the impactful activity of compound 5v against S. sclerotiorum, achieving over 98% curative and protective efficacies at the concentration of 200 μg/mL. Further mechanistic investigations unveiled that compound 5v induced mycelial shrinkage and collapse in S. sclerotiorum, resulting in organelle damage and the accumulation of antioxidant enzyme activity., Conclusion: The significant antifungal efficacy of the prepared thymol derivatives shall encourage further exploration of compound 5v as a promising candidate to develop novel fungicides for crop protection. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)