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1.
J Colloid Interface Sci ; 606(Pt 2): 1800-1810, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34507171

RESUMO

Ag3PO4-based photocatalysts have been deeply studied in environmental remediation; however, two problems limited their further application: photocorrosion and quenching effect by in-situ generated H2O2. To addressed these two questions simultaneously, Fe2(MoO4)3 was coupled with Ag3PO4 to construct Z-scheme Fe2(MoO4)3/Ag/Ag3PO4 heterojunction driven by internal-electric-field. The rhodamine B degradation rate of heterojunction was 254 and 7.0 times higher than those of Fe2(MoO4)3 and Ag3PO4, respectively. The outstanding photoactivity was due to the high visible-light harvest, low interface resistance, high separation efficiency of charge carriers, long lifetime of hole (h+) and electron (e-), well-preserved oxidation potential of h+, and especially photocatalytic produced H2O2 inside the system. The in-situ generated H2O2 was fully activated to be •OH on the Fe2(MoO4)3 surface via a Fenton reaction, leading to the elimination of quenching effect on h+ and e-, and generation of more •OH. Additionally, in Z-scheme heterojunction, e- transferred from Ag3PO4 to Fe2(MoO4)3, avoiding the accumulation on Ag3PO4 surface, and hence suppressing the photocorrosion. As a result, 91.2% of degradation efficiency remained after 5 cycles. This paper provides a new method to simultaneously increase the degradation rate by utilizing the in-situ generated H2O2 and improve the stability of Ag3PO4 via constructing a Z-scheme heterojunction.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120276, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34455379

RESUMO

A new Lanthanum-based luminescent metal-organic framework, {[La(H2O)4(HL)]·H2O} (1), has been successfully synthesized by employing 3,3',5,5'-azodioxybenzenetetracarboxylic acid (H4L) as a rigid organic linker through the solvothermal reactions. 1 exhibits a two-dimensional (2D) layered structure and a three-dimensional (3D) supramolecular structure is formed by hydrogen bonds between the layers. Stability studies indicate that 1 has good chemical stability and thermostability. Meanwhile, the Ksv values for TNP is 4.61 × 104 M-1 with the LOD of 4.13 × 10-6 M and the Ksv value for Fe3+ is 1.22 × 104 M-1 with the LOD of 1.72 × 10-5 M, respectively, which demonstrated that 1 exhibits high sensitivity and excellent selectivity for the detection of TNP and Fe3+via fluorescence quenching. Significantly, 1 shows high regenerability after five recycling progress for sensing Fe3+. The possible mechanisms associated with the luminescent quenching are discussed in detail through some relevant experiments and tests, as well as the DFT calculations. Based on the above excellent properties of 1, it will have extremely potential to be used as a dual functional sensor for both detecting TNP and Fe3+ in aqueous solution, simultaneously.

3.
ISA Trans ; 119: 65-73, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33676739

RESUMO

This paper addresses the robust stochastic finite-time and fixed-time chaos synchronization of two permanent magnet synchronous motors (PMSMs) in noise environment. The novel adaptive finite-time and fixed-time control schemes are implemented, respectively, which can not only ensure that the stochastic chaos synchronization of PMSMs can be achieved in a fast rate, but also determine the control gains successfully(not necessary to set them in advance). The sufficient conditions are derived in the light of the stochastic finite-time and fixed-time stability theories, where the upper bound of synchronization time can be estimated. Furthermore, the stochastic fixed-time synchronization can get rid of the dependence of initial conditions in PMSMs, which overcomes the critical deficiency of stochastic finite-time synchronization of PMSMs. Finally, simulation results demonstrate the validity of proposed theoretical analysis with comparisons.

4.
J Environ Manage ; 301: 113839, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592663

RESUMO

The ecological compensation (EC) mechanism is an innovative institutional arrangement which can effectively realize the coordinated development of social-economic growth and ecological protection. The current research on the evaluation of the implementation effect of EC mechanism mainly focuses on its environmental performance, how the EC mechanism guides the economically underdeveloped areas in the upper reaches of the basin to embark on the road of high-quality economic development, especially the mechanism of how EC triggers the optimization and upgrading of industrial structure, it is a topic worthy of in-depth discussion. This study takes China's first cross-provincial horizontal EC mechanism pilot (Xin'an River Basin EC) as the research object and regards it as a quasi-natural experiment. This paper selects the annual panel data of the 11 cities involved from 2009 to 2019 and builds a DID model to study the mechanism of EC affecting industrial structure adjustment systematically. The results show that the EC mechanism mainly promotes the adjustment of the industrial structure in the pilot area through two paths, this is achieved by triggering the transfer of backward or highly polluting industries and promoting the upgrading of the industrial structure. At the same time, technological innovation plays a part intermediary role in the impact of EC to promote the upgrading of industrial structure. Further analysis found that the larger the funds of compensation input, the higher the assessment intensity, the better the effects are. Finally, this study puts forward relevant policy recommendations to further release the potential of the horizontal EC for the reference of decision-makers.


Assuntos
Desenvolvimento Econômico , Indústrias , China , Cidades , Invenções , Rios
5.
J Hazard Mater ; 423(Pt A): 127098, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523485

RESUMO

Nano zero-valent iron (nZVI) is an effective material for Cr(VI) treatment, however excessive agglomeration and surface oxidation limit its application. Herein, straw derived hierarchically porous carbon supported FeNi bimetallic nanoparticles (FeNi@HPC) was prepared for effective removal of Cr(VI) from water. FeNi nanoparticles were successfully loaded onto HPC with good dispersibility, and HPC caused an increase in specific surface area of FeNi nanoparticles. FeNi@HPC exhibited a significantly enhanced removal efficiency for Cr(VI) in comparison to Fe@HPC and FeNi NPs. The Ni doping content was further optimized, and the best Ni content in bimetallic NPs was estimated as 10 wt%. The conditions optimal for the activity of FeNi@HPC were assessed, and the highest removal efficiency equivalent to 30 mg L-1 of Cr(VI) was achieved at pH= 4.0 in 360 min with a dosage of 0.5 g L-1. Higher temperatures favored the removal of Cr(VI) and FeNi@HPC manifested the lowest activation energy as compared to Fe@HPC and FeNi NPs. The action mechanisms of FeNi@HPC presumably involved electron transfer from Fe0, Fe2+and atomic hydrogen. This work not only provide a cost-effective and available HPC material to stabilize nZVI but also revealed that using FeNi@HPC is a promising approach for the remediation of water pollution.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 266: 120419, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34619506

RESUMO

Nitroaromatic compounds (NACs) can lead to various environmental pollution healh problems. In order to effectively recognize and sense NACs, a novel coordination polymers (CPs) with fluorescent characteristic [Zn3(btc)2(tpt)(H2O)2]·4H2O (1) (tpt = tris(4-pyridyl)triazine, H3btc = 1,3,5-benzenetricarboxylic acid) has been triumphantly prepared as an fluorescence probe by solvothermal method. 1 possesses remarkable PH stability ranging from 2.0 to 12.0 and is also stable in different pure organic solvents. It should be noted that 1 manifests a fluorescence quenching response against the detection of selectivity and sensitivity towards 2,4,6-trinitrophenol (TNP) in aqueous solution. It also makes analysis on the limit of detection towards TNP, which is as low as 0.94 µM compared with most reported CPs sensors for TNP. Therefore, 1 can become a satisfactory sensor for TNP detection with remarkable selectivity, strong anti-interference and favorable recyclability. In addition, the quenching mechanisms were also discussed. It was supposed that the mechanisms of photoinduced electron transfer (PET) as well as resonance energy transfer (RET) might be the main influencing factors.


Assuntos
Luminescência , Polímeros , Picratos , Zinco
7.
Bioresour Technol ; 343: 126100, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34626760

RESUMO

The development of lignocellulosic biorefineries requires a first stage of pretreatment which enables the efficient valorization of all fractions present in this renewable material. In this sense, this review aims to show the main advantages of hydrothermal treatment as a first step of a biorefinery infrastructure using hardwood as raw material, as well as, main drawback to overcome. Hydrothermal treatment of hardwood highlights for its high selectivity for hemicelluloses solubilization as xylooligosaccharides (XOS). Nevertheless, the suitable conditions for XOS production are inadequate to achieve an elevate cellulose to glucose conversion. Hence, several strategies namely the combination of hydrothermal treatment with delignification process, in situ modification of lignin and the mixture with another renewable resources (concretely, seaweeds, and by-products generated in the food industry with high sugar content) were pinpointed as promising alternative to increase the final ethanol concentration coupled with XOS recovery in the hydrolysate.


Assuntos
Lignina , Oligossacarídeos , Celulose , Glucuronatos , Hidrólise
8.
Small ; : e2104244, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741412

RESUMO

Ultraviolet detection is of great significance due to its wide applications in the missile tracking, flame detecting, pollution monitoring, and so on. The nonlayered semiconductor γ-Bi2 O3 is a promising candidate toward high-performance UV detection due to the wide bandgap, excellent light sensitivity, environmental stability, nontoxic and elemental abundance properties. However, controllable preparation of ultrathin 2D γ-Bi2 O3 flakes remains a challenge, owing to its nonlayered structure, metastable nature, and other competing phases. Moreover, the UV photodetectors based on 2D γ-Bi2 O3 flake have not been implemented yet. Here, ultrathin (down to 4.8 nm) 2D γ-Bi2 O3 flakes with high crystal quality are obtained via a van der Waals epitaxy method. The as-synthesized single-crystalline γ-Bi2 O3 flakes show a body-centered cubic structure and grown along (111) lattice plane as revealed by experimental observations. More importantly, photodetectors based on the as-synthesized 2D γ-Bi2 O3 flakes exhibit promising UV detection ability, including a responsivity of 64.5 A W-1 , a detectivity of 1.3 × 1013 Jones, and an ultrafast response speed (τrise  ≈ 290 µs and τdecay  ≈ 870 µs) at 365 nm, suggesting its great potential for various optoelectronic applications.

9.
Biomed Opt Express ; 12(10): 6277-6283, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34745736

RESUMO

Reflection-type photoplethysmography (PPG) pulse sensors are widely used in consumer markets to measure cardiovascular signals. Different from off-chip package solutions in which the light-emitting diode (LED) and photodetector (PD) are in separate chips, a GaN integrated optoelectronic chip with a novel ring structure is proposed to realize a PPG pulse sensor. The integrated optoelectronic chip consists of two multiple-quantum well (MQW) diodes. For higher sensitivities, the central and peripheral MQW diodes are suitable as the LED and PD, respectively. The results indicate that the integrated optoelectronic chip based on a blue LED epitaxial wafer is more suitable for the integrated PPG sensor based on device performance. Moreover, the amplitude of the PPG pulse signal collected from fingertips is higher than that from a wrist. The feasibility of the reflection-type PPG pulse sensor based on a GaN integrated optoelectronic chip is fully verified with the advantages of smaller sizes and lower costs.

10.
iScience ; 24(11): 103221, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34746695

RESUMO

Neurodegenerative diseases are challenging for systems biology because of the lack of reliable animal models or patient samples at early disease stages. Induced pluripotent stem cells (iPSCs) could address these challenges. We investigated DNA, RNA, epigenetics, and proteins in iPSC-derived motor neurons from patients with ALS carrying hexanucleotide expansions in C9ORF72. Using integrative computational methods combining all omics datasets, we identified novel and known dysregulated pathways. We used a C9ORF72 Drosophila model to distinguish pathways contributing to disease phenotypes from compensatory ones and confirmed alterations in some pathways in postmortem spinal cord tissue of patients with ALS. A different differentiation protocol was used to derive a separate set of C9ORF72 and control motor neurons. Many individual -omics differed by protocol, but some core dysregulated pathways were consistent. This strategy of analyzing patient-specific neurons provides disease-related outcomes with small numbers of heterogeneous lines and reduces variation from single-omics to elucidate network-based signatures.

11.
Anal Chim Acta ; 1187: 339131, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34753581

RESUMO

Dengue fever caused by Dengue virus (DENV) infection has been widely popular, especially in tropical and subtropical areas. Rapid and sensitive diagnosis is the first priority for treatment of DENV infection. This work designed a signal amplification strategy for sensitive electrochemical detection of DENV by using a clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a system for catalytic hairpin assembly on electrode surface. The presence of target RNA could activate the cleavage activity of the CRISPR/Cas13a system to release the blocker silenced swing arms, which then hybridized with hairpin 1 (H1) immobilized on electrode surface to expose the pre-locked toehold domain of H1 for the hybridization of ferrocene-labeled hairpin 2 (H2-Fc). Eventually, a large number of H2-Fc were captured to the electrode to produce amperometric signal for achieving signal amplification. This method showed a linear detection range from 5 fM to 50 nM with a detection limit of 0.78 fM. The proposed assay was successfully used to detect DENV type 1 in total RNA sample extracted, indicating great potential for application in early clinical diagnostic.


Assuntos
Técnicas Biossensoriais , Vírus da Dengue , Catálise , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Vírus da Dengue/genética , Técnicas Eletroquímicas , Limite de Detecção , Hibridização de Ácido Nucleico
12.
Front Genet ; 12: 773009, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733322

RESUMO

Hearing loss (HL) is one of the most common disabilities in the world. In industrialized countries, HL occurs in 1-2/1,000 newborns, and approximately 60% of HL is caused by genetic factors. Next generation sequencing (NGS) has been widely used to identify many candidate genes and variants in patients with HL, but the data are scattered in multitudinous studies. It is a challenge for scientists, clinicians, and biologists to easily obtain and analyze HL genes and variant data from these studies. Thus, we developed a one-stop database of HL-related genes and variants, Gene4HL (http://www.genemed.tech/gene4hl/), making it easy to catalog, search, browse and analyze the genetic data. Gene4HL integrates the detailed genetic and clinical data of 326 HL-related genes from 1,608 published studies, along with 62 popular genetic data sources to provide comprehensive knowledge of candidate genes and variants associated with HL. Additionally, Gene4HL supports the users to analyze their own genetic engineering network data, performs comprehensive annotation, and prioritizes candidate genes and variations using custom parameters. Thus, Gene4HL can help users explain the function of HL genes and the clinical significance of variants by correlating the genotypes and phenotypes in humans.

13.
Eur J Pharmacol ; 912: 174581, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34743979

RESUMO

Sepsis is a systemic inflammatory response syndrome caused by a host's immune response to infection. Acute lung injury (ALI) is one of the most common complications of sepsis with high mortality and morbidity. Recent evidence demonstrated that the 'gut-lung axis' was related to the progression of septic acute lung injury, which regarded gut microbiota and intestinal barrier as two critical factors correlated with acute lung injury. Sinomenine is an isoquinoline alkaloid component extracted from Sinomenium acutum Rehd,et Wils, which has been already reported to have significant anti-inflammatory, immunosuppressive, and anti-arthritis properties. In this research, we observed that sinomenine could repair the lung injury and alleviate inflammatory response induced by cecum ligation and puncture (CLP). Illumine sequencing of 16S rDNA revealed that sinomenine could improve the richness of gut microbiota and modulate the composition of intestinal flora in cecum ligation and puncture mice. Meanwhile, sinomenine could reduce the colon pathological damage and improve the intestine barrier integrity in cecum ligation and puncture mice. We also found that the molecular mechanism of sinomenine's protective effect on intestinal tract was related to the activation of aryl hydrocarbon receptor/nuclear factor erythroid-2 related factor 2(Nrf2)pathway both in vivo and vitro experiments. Collectively, the prevention of septic acute lung injury by sinomenine might be mediated by modulating gut microbiota and restoring intestinal barrier via aryl hydrocarbon receptor/Nrf2-dependent pathway.

15.
Nucleic Acids Res ; 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792173

RESUMO

For many RNA molecules, the secondary structure is essential for the correct function of the RNA. Predicting RNA secondary structure from nucleotide sequences is a long-standing problem in genomics, but the prediction performance has reached a plateau over time. Traditional RNA secondary structure prediction algorithms are primarily based on thermodynamic models through free energy minimization, which imposes strong prior assumptions and is slow to run. Here, we propose a deep learning-based method, called UFold, for RNA secondary structure prediction, trained directly on annotated data and base-pairing rules. UFold proposes a novel image-like representation of RNA sequences, which can be efficiently processed by Fully Convolutional Networks (FCNs). We benchmark the performance of UFold on both within- and cross-family RNA datasets. It significantly outperforms previous methods on within-family datasets, while achieving a similar performance as the traditional methods when trained and tested on distinct RNA families. UFold is also able to predict pseudoknots accurately. Its prediction is fast with an inference time of about 160 ms per sequence up to 1500 bp in length. An online web server running UFold is available at https://ufold.ics.uci.edu. Code is available at https://github.com/uci-cbcl/UFold.

16.
Pain Physician ; 24(8): 495-506, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34793634

RESUMO

BACKGROUND: Chronic musculoskeletal pain (CMP) management is a major global public health goal owing to increased social and economic burdens. However, the risk of CMP in smokers compared with nonsmokers remains uncertain. OBJECTIVES: This study aims to determine the magnitude and importance of the relationship between cigarette smoking and risk of CMP. STUDY DESIGN: A meta-analysis of the CMP risk of cigarette smokers. METHODS: We systematically searched PubMed, Embase, and Cochrane library databases from inception to August 2020. Data extraction and quality assessment were performed by 2 independent reviewers using a standardized extraction checklist. Data were pooled using a random-effects model. RESULTS: In this meta-analysis of 32 studies involving 296,109 participants, current smoking was associated with increased CMP risk (OR: 1.23, 95% CI: 1.09-1.40), whereas ever and past smoking did not show such an association (OR: 1.14, 95% CI: 0.95-1.37; OR: 1.06, 95% CI: 0.83-1.35, respectively). Stratified analyses showed that there was a marked significance in almost all strata of current smokers compared with non-smokers, except for mean age (>= 50 years), location of pain (neck pain, sacral pain, and knee pain), smoking frequency (occasionally), study design (cross-sectional), mean follow-up (< 10 years), and adjustment for confounding factors (>= 6). Interestingly, there was statistically negative association between cigarette smoking and knee pain risk in current smokers, ever smokers, and past smokers. LIMITATIONS: The major limitation of this meta-analysis relates to the heterogeneities across included studies. CONCLUSIONS: Cigarette smoking was associated with increased risk of CMP. In view of the high prevalence of smoking in many countries and the increasing number of CMP patients worldwide, reducing tobacco use should be an important public health strategy to prevent and control the global epidemic of CMP. Future research should attempt to establish whether this association is causal and clarify its mechanisms.

17.
Sleep Med ; 88: 267-273, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34801825

RESUMO

BACKGROUND: Currently, there is no consensus on the effect of sleep deprivation on male serum testosterone. This systematic review and meta-analysis aimed to determine the association between partial/total sleep deprivation and male serum testosterone level. METHODS: The literature related to sleep deprivation and male serum testosterone in the PubMed, Embase, and Cochrane Library databases were searched from their inception to July 15, 2021. Data were pooled using the Stata 15 software. The results were presented as standard mean differences (SMDs) with their 95% confidence intervals (CIs). RESULTS: Eighteen studies involving 252 men were included in the systematic review and meta-analysis. The findings revealed that short-term partial sleep deprivation had no significant effect on male serum testosterone (SMD = -0.22; 95% CI: -0.5, 0.06; P = 0.13), while total sleep deprivation reduced the male testosterone levels (SMD = -0.64; 95% CI: -0.87, -0.42; P < 0.001). According to the intervention duration of total sleep deprivation, subgroup analysis was conducted by a fixed-effects model. The results revealed that the serum testosterone was significantly decreased after 24 h total sleep deprivation (SMD = - 0.67; 95% CI = - 0.93, -0.42, P < 0.001), as well as 40-48 h total sleep deprivation (SMD = - 0.74; 95% CI = - 1.22, -0.26, P = 0.002). CONCLUSIONS: This meta-analysis revealed that total sleep deprivation (more than or equal to 24 h) reduces the male testosterone levels, while short-term partial sleep deprivation has no significant effect on male serum testosterone. Sleep duration plays a pivotal role in maintaining male serum testosterone levels.

18.
Psychol Aging ; 36(7): 822-833, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34766800

RESUMO

We investigated parafoveal processing by 44 young (18-30 years) and 44 older (65+ years) Chinese readers using eye movement measures. Participants read sentences which included an invisible boundary after a two-character word (N) and before two one-character words (N + 1, N + 2). Before a reader's gaze crossed the boundary, N + 1 and N + 2 were shown normally or masked (i.e., as valid/invalid previews), after which they reverted to normal. Young adults obtained preview benefits (a processing advantage for valid over invalid previews) for both words. However, older adults obtained N + 2 preview benefits only when N + 1 was valid, suggesting their parafoveal processing is more limited. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Reconhecimento Visual de Modelos , Leitura , Idoso , Envelhecimento , China , Fóvea Central , Humanos
19.
bioRxiv ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34816260

RESUMO

Unlike SARS-CoV-1 and MERS-CoV, infection with SARS-CoV-2, the viral pathogen responsible for COVID-19, is often associated with neurologic symptoms that range from mild to severe, yet increasing evidence argues the virus does not exhibit extensive neuroinvasive properties. We demonstrate SARS-CoV-2 can infect and replicate in human iPSC-derived neurons and that infection shows limited anti-viral and inflammatory responses but increased activation of EIF2 signaling following infection as determined by RNA sequencing. Intranasal infection of K18 human ACE2 transgenic mice (K18-hACE2) with SARS-CoV-2 resulted in lung pathology associated with viral replication and immune cell infiltration. In addition, ∼50% of infected mice exhibited CNS infection characterized by wide-spread viral replication in neurons accompanied by increased expression of chemokine ( Cxcl9, Cxcl10, Ccl2, Ccl5 and Ccl19 ) and cytokine ( Ifn-λ and Tnf-α ) transcripts associated with microgliosis and a neuroinflammatory response consisting primarily of monocytes/macrophages. Microglia depletion via administration of colony-stimulating factor 1 receptor inhibitor, PLX5622, in SARS-CoV-2 infected mice did not affect survival or viral replication but did result in dampened expression of proinflammatory cytokine/chemokine transcripts and a reduction in monocyte/macrophage infiltration. These results argue that microglia are dispensable in terms of controlling SARS-CoV-2 replication in in the K18-hACE2 model but do contribute to an inflammatory response through expression of pro-inflammatory genes. Collectively, these findings contribute to previous work demonstrating the ability of SARS-CoV-2 to infect neurons as well as emphasizing the potential use of the K18-hACE2 model to study immunological and neuropathological aspects related to SARS-CoV-2-induced neurologic disease. Importance: Understanding the immunological mechanisms contributing to both host defense and disease following viral infection of the CNS is of critical importance given the increasing number of viruses that are capable of infecting and replicating within the nervous system. With this in mind, the present study was undertaken to evaluate the role of microglia in aiding in host defense following experimental infection of the central nervous system (CNS) of K18-hACE2 with SARS-CoV-2, the causative agent of COVID-19. Neurologic symptoms that range in severity are common in COVID-19 patients and understanding immune responses that contribute to restricting neurologic disease can provide important insight into better understanding consequences associated with SARS-CoV-2 infection of the CNS.

20.
Chem Commun (Camb) ; 57(94): 12603-12606, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34761780

RESUMO

A mild copper-catalyzed four-component selenosulfonylation of alkynes, cycloketone oxime esters, DABCO (SO2)2 and diselenides has been developed. This method enables the rapid assembly of ß-cyanoalkylsulfonylated vinyl selenides in moderate to good yields. Advantages of this protocol include a broad substrate scope, good functional group tolerance and the late-stage functionalization of complex molecules. Moreover, the potential utility of this methodology is demonstrated through simple oxidation of the products to access synthetically important alkynyl sulfones. Mechanistic studies suggest that a cyanoalkylsulfonyl radical intermediate is involved in this process.

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