Search

Based on the capability of silyl ethers for efficient glycosylation, the new MTEAN glycosylation protocol utilizing 8-methyltosylaminoethynyl-1-naphthyl (MTEAN) glycosides as donors were extended to one-pot synthesis of nucleosides, late-stage modification of bioactive molecules, and stereoselective construction of 1,2-cis-glucosidic linkages using silyl ethers of the acceptors. Moreover, the reaction mechanism was systematically investigated by control reactions and side product characterizations, leading to the determination of a TfOH-catalyzed ynamide functionality-initiated process, which was further corroborated by identifications of the departure form of leaving group and the real catalyst. [ABSTRACT FROM AUTHOR]

Virus infection can alter immune regulatory activity, and thus may be involved in the occurrence of autoimmune diseases. Recently, the pandemic of COVID-19 has posed a huge threat to public health and emerging evidence suggests that coronavirus may be implicated in the development and pathogenesis of autoimmune diseases. However, how coronavirus infection impacts the risk of autoimmune disease remains largely unknown. In this review, we focused on the association between coronavirus and autoimmunity, and elucidated the molecular mechanisms linking coronavirus exposure to autoimmunity. Additionally, we briefly introduced the role that coronavirus plays in several autoimmune diseases including multiple sclerosis (MS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and idiopathicthrombocytopenic purpura (ITP). [ABSTRACT FROM AUTHOR]

Taking advantage of the reliable stereocontrol capability of DMNPA group via long-distance-participation (LDP) effect as well as the mild and efficient deprotection conditions, the first and highly efficient synthesis of digoxin was achieved through a nine-step longest linear sequence with 41% overall yield. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown an association between gut microbiota and cardiovascular diseases (CVDs). However, the underlying causal relationship remains unclear. This study aims to elucidate the causal relationship between gut microbiota and CVDs and to explore the pathogenic role of gut microbiota in CVDs. Methods: In this two-sample Mendelian randomization study, we used genetic instruments from publicly available genome-wide association studies, including single-nucleotide polymorphisms (SNPs) associated with gut microbiota (n = 14,306) and CVDs (n = 2,207,591). We employed multiple statistical analysis methods, including inverse variance weighting, MR Egger, weighted median, MR pleiotropic residuals and outliers, and the leave-one-out method, to estimate the causal relationship between gut microbiota and CVDs. Additionally, we conducted multiple analyses to assess horizontal pleiotropy and heterogeneity. Results: GWAS summary data were available from a pooled sample of 2,221,897 adult and adolescent participants. Our findings indicated that specific gut microbiota had either protective or detrimental effects on CVDs. Notably, Howardella (OR = 0.955, 95% CI: 0.913–0.999, P =.05), Intestinibacter (OR = 0.908, 95% CI:0.831–0.993, P =.03), Lachnospiraceae (NK4A136 group) (OR = 0.904, 95% CI:0.841–0.973, P =.007), Turicibacter (OR = 0.904, 95% CI: 0.838–0.976, P =.01), Holdemania (OR, 0.898; 95% CI: 0.810–0.995, P =.04) and Odoribacter (OR, 0.835; 95% CI: 0.710–0.993, P =.04) exhibited a protective causal effect on atrial fibrillation, while other microbiota had adverse causal effects. Similar effects were observed with respect to coronary artery disease, myocardial infarction, ischemic stroke, and hypertension. Furthermore, reversed Mendelian randomization analyses revealed that atrial fibrillation and ischemic stroke had causal effects on certain gut microbiotas. Conclusion: Our study underscored the importance of gut microbiota in the context of CVDs and lent support to the hypothesis that increasing the abundance of probiotics or decreasing the abundance of harmful bacterial populations may offer protection against specific CVDs. Nevertheless, further research is essential to translate these findings into clinical practice. [ABSTRACT FROM AUTHOR]

C32H48CoMo2N16O7, triclinic, P 1 ‾ (no. 2), a = 10.425(2) Å, b = 10.517(2) Å, c = 11.187(2) Å, α = 94.671(7)°, β = 112.270(6)°, γ = 104.108(7)°, V = 1080.0(3) Å3, Z = 1, Rgt(F) = 0.0407, wRref(F2) = 0.1015, T = 273 K. [ABSTRACT FROM AUTHOR]

C24H36N6O28V10, monoclinic, P21/c (no. 14), a = 10.4869(6) Å, b = 11.5123(7) Å, c = 17.4627(9) Å, β = 108.459(3)°, V = 1999.8(2) Å3, Z = 2, Rgt(F) = 0.0209, wRref(F2) = 0.0582, T = 296 K. [ABSTRACT FROM AUTHOR]

Two new long-chain unsaturated compounds, (2E, 6E)-10-methoxy-3,7-dimethyl-10-oxodeca-2,6-dienoic acid (1) and (2E, 6E)-3,7,11-trimethyldodeca-2,6-dienedioic acid (2), together with seven known compounds were isolated from a marine-derivedStreptomycessp. Their structures were determined by spectroscopic methods, including 2D NMR techniques. Compounds1and2were investigated for their antibacterial activities. [ABSTRACT FROM PUBLISHER]

For achieving a uniform and stable suspension of CeO2 nanoparticles in aqueous medium, Al3+ was doped into the lattice of CeO2 by hydrothermal treatment. Although the doping will increase the probability of adhesion of primary particles with the size of 7 nm, it can effectively prevent the agglomeration between CeO2 particles, greatly improve the dispersion uniformity and suspension stability of particles, greatly narrow the particle size distribution of secondary particles, and make the degree of particle agglomeration controllable. Meantime, the UV absorption property of the product was improved and the absorption peak was red shifted after Al3+ doping. [ABSTRACT FROM AUTHOR]

Impaired activation and regulation of the extinction of inflammatory cells and molecules in injured neuronal tissues are key factors in the development of epilepsy. SerpinA3N is mainly associated with the acute phase response and inflammatory response. In our current study, transcriptomics analysis, proteomics analysis, and Western blotting showed that the expression level of Serpin clade A member 3N (SerpinA3N) is significantly increased in the hippocampus of mice with kainic acid (KA)-induced temporal lobe epilepsy, and this molecule is mainly expressed in astrocytes. Notably, in vivo studies using gain- and loss-of-function approaches revealed that SerpinA3N in astrocytes promoted the release of proinflammatory factors and aggravated seizures. Mechanistically, RNA sequencing and Western blotting showed that SerpinA3N promoted KA-induced neuroinflammation by activating the NF-κB signaling pathway. In addition, co-immunoprecipitation revealed that SerpinA3N interacts with ryanodine receptor type 2 (RYR2) and promotes RYR2 phosphorylation. Overall, our study reveals a novel SerpinA3N-mediated mechanism in seizure-induced neuroinflammation and provides a new target for developing neuroinflammation-based strategies to reduce seizure-induced brain injury. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the stems ofKadsura renchangianaled to the isolation of two new sesquiterpenoids, renchangianins F and G (1and2). Their structures were elucidated by spectroscopic methods, including 2D NMR techniques. Thein vitrocytotoxic activities of the isolates were studied against HepG2, A549, and LN229 cancer cell lines. [ABSTRACT FROM PUBLISHER]

Sodium‐ion batteries capable of operating at rate and temperature extremes are highly desirable, but elusive due to the dynamics and thermodynamics limitations. Herein, a strategy of electrode–electrolyte interfacial chemistry modulation is proposed. The commercial hard carbon demonstrates superior rate performance with 212 mAh g−1 at an ultra‐high current density of 5 A g−1 in the electrolyte with weak ion solvation/desolvation, which is much higher than those in common electrolytes (nearly no capacity in carbonate‐based electrolytes). Even at −20 °C, a high capacity of 175 mAh g−1 (74 % of its room‐temperature capacity) can be maintained at 2 A g−1. Such an electrode retains 90 % of its initial capacity after 1000 cycles. As proven, weak ion solvation/desolvation of tetrahydrofuran greatly facilitates fast‐ion diffusion at the SEI/electrolyte interface and homogeneous SEI with well‐distributed NaF and organic components ensures fast Na+ diffusion through the SEI layer and a stable interface. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries capable of operating at rate and temperature extremes are highly desirable, but elusive due to the dynamics and thermodynamics limitations. Herein, a strategy of electrode–electrolyte interfacial chemistry modulation is proposed. The commercial hard carbon demonstrates superior rate performance with 212 mAh g−1 at an ultra‐high current density of 5 A g−1 in the electrolyte with weak ion solvation/desolvation, which is much higher than those in common electrolytes (nearly no capacity in carbonate‐based electrolytes). Even at −20 °C, a high capacity of 175 mAh g−1 (74 % of its room‐temperature capacity) can be maintained at 2 A g−1. Such an electrode retains 90 % of its initial capacity after 1000 cycles. As proven, weak ion solvation/desolvation of tetrahydrofuran greatly facilitates fast‐ion diffusion at the SEI/electrolyte interface and homogeneous SEI with well‐distributed NaF and organic components ensures fast Na+ diffusion through the SEI layer and a stable interface. [ABSTRACT FROM AUTHOR]

Target synthesis of hydrocarbons from abundant biomass is highly desired for sustainable aviation fuels (SAFs) to meet the need for both net zero carbon emission and air pollution control. However, precise hydrodeoxygenation (PHDO) of bio-based furan compounds and cyclic ethers to isomerically pure alkanes remains a challenge in heterogenous catalysis, which usually requires delicate control of the distribution of acid and metal catalytic sites in nanoconfined space. Here we show that a nanoporous acidic metal–organic framework (MOF), namely MIL-101-SO3H, enables one-pot PHDO reactions from furan-derivative oxygenates to solely single-component alkanes by just mechanical mixing with commercial Pd/C towards highly efficient and highly selective hydrocarbon production. The superior performance of such tandem catalysts can be attributed to the preferential adsorption of oxygenate precursors and expulsion of deoxygenated intermediates benefiting from Lewis acid sites embedded in the MOF. The strong Brønsted acidity of MIL-101-SO3H is contributed by both the –SO3H groups and the adsorbed H2O, which makes it a water-tolerant solid acid for durable PHDO processes. The simplicity of mechanical mixing of different heterogenous catalysts allows the modulation of the tandem catalysis system for optimization of the ultimate catalytic performance. [ABSTRACT FROM AUTHOR]

Controllable three-dimensional villose titanium dioxide architectures grown on carbon textiles are fabricated by a facile one-step in-situ hydrothermal method at low temperatures. It has in fact been proven to be an effective method to reduce self-aggregation and promote lithium-ion intercalate/extract via building 3D architectures based on 2D conductive materials. More importantly, the freestanding electrodes without any addition of conductive agents and polymeric binders reveal significant improvement in high-rate capacity and cycling performance. [ABSTRACT FROM AUTHOR]