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1.
J Colloid Interface Sci ; 673: 504-516, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38879992

ABSTRACT

Herein, a composite of N-doped carbon coated phosphating cobalt hollow nanofibers (N/C@CoP-HNFs) was synthesized by electrospinning, phosphating, and carbon coating processes. When employed as multifunctional electrode materials for potassium-ion batteries (PIBs) and lithium-sulfur (Li-S) batteries, the N/C@CoP-HNFs demonstrated notable electrochemical properties. Specifically, it delivered an initial specific capacity of 420.4 mA h g-1 at a current density of 100 mA g-1, with a sustained capacity of 190.8 mA h g-1 after 200 cycles in PIBs, and a specific capacity of 1448 mA h g-1 at a current density of 0.5C in Li-S batteries, which is considered relatively high for these types of battery technology. This good performance may due to the combination of the carbon nitrogen layer and cobalt phosphide bilayer hollow tube structure, which is conducive to telescoping the diffusion length of ions and electrons and buffer volume variation, and effectively inhibits the shuttle effect. Density functional theory (DFT) calculations were also used to explore the energy storage mechanism of the material. The possible adsorption sites and corresponding adsorption energy of K+ were analyzed, and the advantages of the material were explored by calculating the diffusion barrier and state density. The theoretical simulations further validated the strong adsorption capability of CoP for polysulfides. This work is expected to provide new ideas for new energy storage materials.

2.
J Phys Chem A ; 128(17): 3273-3284, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38635947

ABSTRACT

Herein, we report a computation study based on the density functional theory calculations to understand the mechanism and ligand effect of the base-stabilized dialumenes toward dihydrogen activation. Among all of the examined modes of dihydrogen activation using the base-stabilized dialumene, we found that the concerted 1,2-hydrogenation of the Al═Al double bond is kinetically more preferable. The concerted 1,2-hydrogenation of the Al═Al double bond adopts an electron-transfer model with certain asynchrony. That is, the initial electron donation from the H-H σ bonding orbital to the empty 3p orbital of the Al1 center is followed by the backdonation from the lone pair electron of the Al2 center to the H-H σ antibonding orbital. Combined with the energy decomposition analysis on the transition states of the concerted 1,2-hydrogenation of the Al═Al double bond and the topographic steric mapping analysis on the free dialumenes, we ascribe the higher reactivity of the aryl-substituted dialumene over the silyl-substituted analogue in dihydrogen activation to the stronger electron-withdrawing effect of the aryl group, which not only increases the flexibility of the Al═Al double bond but also enhances the Lewis acidity of the Al═Al core. Consequently, the aryl-substituted dialumene fragment suffers less geometric deformation, and the orbital interactions between the dialumene and dihydrogen moieties are more attractive during the 1,2-hydrogenation process. Moreover, our calculations also predict that the Al═Al double bond has a good tolerance with the stronger electron-withdrawing group (-CF3) and the weaker σ-donating N-heterocyclic carbene (NHC) analogue (e.g., triazol carbene and NHSi). The reactivity of the dialumene in dihydrogen activation can be further improved by introducing these groups as the supporting ligand and the stabilizing base on the Al═Al core, respectively.

3.
Chem Commun (Camb) ; 60(26): 3579-3582, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38470069

ABSTRACT

A DMP-initiated metal-free effective ß,γ-asymmetric spirocyclopropanation of propanols strategy using oxidative iminium activation is described. This process has been realized by a synergistic amine-catalyzed one-pot cascade oxidation-Michael addition cyclopropanation for "one-pot" access to various spirocyclopropyl propionaldehydes/propanols from diverse 3-arylpropanols and α-brominated active methylene compounds under mild conditions and with high enantioselectivity (ee up to >99%).

4.
Chem Commun (Camb) ; 59(47): 7255-7258, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37222758

ABSTRACT

We developed an electrochemical strategy for the synthesis of quinones through direct oxidation of widely accessible arenes and heteroarenes under mild conditions. A variety of quinones and hetero quinones were prepared with moderate to good yields, without the involvement of the pre-functionalized substrates. In addition, this atom economic method also exhibits wide functional group tolerance, including C(sp2)-I bond, ester, aldehyde, and OTf groups. This synthetic approach provides a straightforward and atom economic method for the transformation of C(sp2)-H bonds.


Subject(s)
Quinones , Oxidation-Reduction
5.
J Org Chem ; 88(9): 5248-5253, 2023 May 05.
Article in English | MEDLINE | ID: mdl-37023248

ABSTRACT

Direct para-selective C(sp2)-H alkylation of electron-deficient arenes based on the electroreduction-enabled radical addition of alkyl bromides has been developed under mild conditions. In the absence of any metals and redox agents, the simple electrolysis system tolerates a variety of primary, secondary, and tertiary alkyl bromides and behaves as an important complement to the directed alkylation of the C(sp2)-H bond and the classic Friedel-Crafts alkylation. This electroreduction process provides a more straightforward, environmentally benign, and effective alkylation method for electron-deficient arenes.

6.
Chemistry ; 29(29): e202300367, 2023 May 22.
Article in English | MEDLINE | ID: mdl-36905399

ABSTRACT

A straightforward synthesis approach to chiral 1-aryl-2-aminoethanols via the one-pot asymmetric hydrogenation catalyzed by Ir catalyst was developed. This tandem process involves the in situ generation of α-amino ketones via the nucleophilic substitution of α-bromoketones with amines and the Ir-catalyzed asymmetric hydrogenation of ketone intermediates to provide diverse enantiomerically enriched ß-amino alcohols. The excellent yields and enantioselectivities (up to 96 % yield and up to >99 % ee) with a wide substrate scope in this one-pot strategy were obtained.

7.
J Org Chem ; 88(5): 2942-2951, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36787380

ABSTRACT

An iridium catalytic system with a ferrocene-based phosphine ligand bearing a modular and tunable unsymmetrical vicinal diamine scaffold was developed for the asymmetric hydrogenation of aryl ketones. This approach provided a powerful tool for the enantioselective synthesis of diverse chiral alcohols with excellent reactivity and enantioselectivity (up to 99% yield, up to 99% ee, and up to 50,000 turnover number). The substituents and chirality of unsymmetrical diamines in ligands played an important role in the satisfactory results.

8.
Chem Commun (Camb) ; 58(96): 13345-13348, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36373836

ABSTRACT

A three-component reductive coupling reaction of aldehydes, amines and cyanopyridines under electrochemical conditions has been developed. The in situ generated imine and cyanopyridine simultaneously undergo single-electron reduction at the cathode, and afford diarylmethylamines through radical coupling without the participation of reducing agents. The one-pot electrolysis method can modularly obtain various secondary and tertiary amines and exhibits broad functional group compatibility. Mechanistic experiments verify the pivotal reduction step from imine to α-amino radical and reveal the key role of benzoic acid in reducing the reduction potential of imine and cyanopyridine.


Subject(s)
Amines , Electricity , Catalysis , Amination , Imines
9.
J Org Chem ; 87(19): 12677-12687, 2022 Oct 07.
Article in English | MEDLINE | ID: mdl-36102897

ABSTRACT

A general method for the synthesis of phenols from electron-deficient aryl ammonium salts or heteroaryl ammonium salts under mild conditions was developed. Benzaldehyde oxime, acetohydroxamic acid, and hydroxylamine hydrochloride were investigated as hydroxide surrogates respectively. With these hydroxide surrogates, a series of phenols were prepared in yields of 20-98%.

10.
Nat Commun ; 13(1): 4138, 2022 07 16.
Article in English | MEDLINE | ID: mdl-35842447

ABSTRACT

By merging electricity with sulfate, the Ritter-type amination of C(sp3)-H bonds is developed in an undivided cell under room temperature. This method features broad substrate generality (71 examples, up to 93% yields), high functional-group compatibility, facile scalability, excellent site-selectivity and mild conditions. Common alkanes and electron-deficient alkylbenzenes are viable substrates. It also provides a straightforward protocol for incorporating C-deuterated acetylamino group into C(sp3)-H sites. Application in the synthesis or modification of pharmaceuticals or their derivatives and gram-scale synthesis demonstrate the practicability of this method. Mechanistic experiments show that sulfate radical anion, formed by electrolysis of sulfate, served as hydrogen atom transfer agent to provide alkyl radical intermediate. This method paves a convenient and flexible pathway for realizing various synthetically useful transformations of C(sp3)-H bonds mediated by sulfate radical anion generated via electrochemistry.


Subject(s)
Sulfates , Amination , Catalysis , Electrochemistry , Molecular Structure
11.
Org Biomol Chem ; 20(19): 3897-3901, 2022 05 18.
Article in English | MEDLINE | ID: mdl-35481827

ABSTRACT

A nucleophilic aromatic substitution (SNAr) reaction that allowed transition-metal-free C-P bond construction via C-N bond cleavage was developed. The coupling between aryltrimethylammonium salts and secondary phosphines from the in situ reduction of diarylphosphine oxides led to the formation of diverse triarylphosphines with various functional groups. This one-pot process was not only a pertinent SNAr precedent but also a favorable transition-metal-free alternative for C-P coupling.


Subject(s)
Phosphines , Transition Elements , Molecular Structure , Oxides/chemistry , Phosphines/chemistry , Salts/chemistry
12.
Commun Chem ; 5(1): 63, 2022 May 19.
Article in English | MEDLINE | ID: mdl-36697664

ABSTRACT

Chiral γ-amino alcohols are the prevalent structural motifs and building blocks in pharmaceuticals and bioactive molecules. Enantioselective hydrogenation of ß-amino ketones provides a straightforward and powerful tool for the synthesis of chiral γ-amino alcohols, but the asymmetric transformation is synthetically challenging. Here, a series of tridentate ferrocene-based phosphine ligands bearing modular and tunable unsymmetrical vicinal diamine scaffolds were designed, synthesized, and evaluated in the iridium-catalyzed asymmetric hydrogenation of ß-amino ketones. The system was greatly effective to substrates with flexible structure and functionality, and diverse ß-tertiary-amino ketones and ß-secondary-amino ketones were hydrogenated smoothly. The excellent reactivities and enantioselectivities were achieved in the asymmetric delivery of various chiral γ-amino alcohols with up to 99% yields, >99% ee values, and turnover number (TON) of 48,500. The gram-scale reactions with low catalyst loading showed the potential application in industrial synthesis of chiral drugs, such as (S)-duloxetine, (R)-fluoxetine, and (R)-atomoxetine.

13.
Org Lett ; 23(24): 9387-9392, 2021 12 17.
Article in English | MEDLINE | ID: mdl-34881901

ABSTRACT

We develop an electrochemical nickel-catalyzed aminomethylation of aryl bromides under mild conditions. The convergent paired electrolysis makes full use of anode and cathode processes, free of a terminal oxidant, a sacrificial anode, a metal reductant, and a prefunctionalized radical precursor. In addition, this method exhibits wide functional group tolerance (63 examples), including some sensitive substituents and aromatic heterocycles. This redox neutral cross coupling provides a more environmentally friendly and synthetic practical protocol for forging C(sp2)-C(sp3) bonds.

14.
Open Life Sci ; 16(1): 311-322, 2021.
Article in English | MEDLINE | ID: mdl-33851031

ABSTRACT

This study aims to investigate the effects of commercial probiotic supplementation in water on the performance parameters, carcass traits, immune function, and antioxidant capacity of broiler chicks. In the experiment, 120 Arbor Acres (AA) broilers (60 male and 60 female) were randomly allocated into four groups (G) - G1: basal diet and G2, G3, and G4: basal diet with 1% Lactobacillus casei, 1% L. acidophilus, and 1% Bifidobacterium in the water, lasting 42 days. The experimental results revealed that probiotic additives produced positive impacts on body weight, average daily feed intake (ADFI), and average daily weight gain for female chicks, whereas these probiotics significantly reduced ADFI and the feed conversion ratio of male chicks (P < 0.05). Probiotics efficiently improved eviscerated yield and breast yield while reducing the abdominal fat (P < 0.05) for the male broiler chicks. A marked increase was observed in the weight of the spleen, bursa of Fabricius, and thymus in the treatment group (P < 0.05). Besides, probiotics produced a significant effect on the concentrations of immune-related proteins (P < 0.05) and markedly increased the concentrations of antioxidase and digestive enzymes when compared with the control (P < 0.05). The addition of probiotics dramatically reduced the total counts of Escherichia coli and Salmonella and increased the quantity of Lactobacilli (P < 0.05). The results of the present study demonstrated an increase in growth performance, carcass traits, immune function, gut microbial population, and antioxidant capacity by supplementing 1% probiotics (L. casei, L. acidophilus, and Bifidobacterium) in the water for broilers.

15.
Biol Res ; 53(1): 4, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-32014065

ABSTRACT

BACKGROUND: Pigmentation development, is a complex process regulated by many transcription factors during development. With the development of the RNA sequencing (RNA-seq), non-coding RNAs, such as miRNAs, lncRNAs, and circRNAs, are found to play an important role in the function detection of related regulation factors. In this study, we provided the expression profiles and development of ncRNAs related to melanocyte and skin development in mice with black coat color skin and mice with white coat color skin during embryonic day 15 (E15) and postnatal day 7 (P7). The expression profiles of different ncRNAs were detected via RNA-seq and also confirmed by the quantitative real-time PCR (qRT-PCR) method. GO and KEGG used to analyze the function the related target genes. RESULTS: We identified an extensive catalogue of 206 and 183 differently expressed miRNAs, 600 and 800 differently expressed lncRNAs, and 50 and 54 differently expressed circRNAs, respectively. GO terms and pathway analysis showed the target genes of differentially expressed miRNA and lncRNA. The host genes of circRNA were mainly enriched in cellular process, single organism process. The target genes of miRNAs were mainly enriched in chromatin binding and calcium ion binding in the nucleus. The function of genes related to lncRNAs are post translation modification. The competing endogenous RNA (ceRNA) network of lncRNAs and circRNAs displays a complex interaction between ncRNA and mRNA related to skin development, such as Tcf4, Gnas, and Gpnms related to melanocyte development. CONCLUSIONS: The ceRNA network of lncRNA and circRNA displays a complex interaction between ncRNA and mRNA related to skin development and melanocyte development. The embryonic and postnatal development of skin provide a reference for further studies on the development mechanisms of ncRNA during pigmentation.


Subject(s)
Gene Expression Profiling , Melanocytes , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Skin Pigmentation/genetics , Skin/embryology , Animals , Cell Differentiation , Mice , Real-Time Polymerase Chain Reaction
16.
Biol. Res ; 53: 04, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089074

ABSTRACT

BACKGROUND: Pigmentation development, is a complex process regulated by many transcription factors during development. With the development of the RNA sequencing (RNA-seq), non-coding RNAs, such as miRNAs, lncRNAs, and circRNAs, are found to play an important role in the function detection of related regulation factors. In this study, we provided the expression profiles and development of ncRNAs related to melanocyte and skin development in mice with black coat color skin and mice with white coat color skin during embryonic day 15 (E15) and postnatal day 7 (P7). The expression profiles of different ncRNAs were detected via RNA-seq and also confirmed by the quantitative real-time PCR (qRT-PCR) method. GO and KEGG used to analyze the function the related target genes. RESULTS: We identified an extensive catalogue of 206 and 183 differently expressed miRNAs, 600 and 800 differently expressed lncRNAs, and 50 and 54 differently expressed circRNAs, respectively. GO terms and pathway analysis showed the target genes of differentially expressed miRNA and lncRNA. The host genes of circRNA were mainly enriched in cellular process, single organism process. The target genes of miRNAs were mainly enriched in chromatin binding and calcium ion binding in the nucleus. The function of genes related to lncRNAs are post translation modification. The competing endogenous RNA (ceRNA) network of lncRNAs and circRNAs displays a complex interaction between ncRNA and mRNA related to skin development, such as Tcf4 , Gnas , and Gpnms related to melanocyte development. CONCLUSIONS: The ceRNA network of lncRNA and circRNA displays a complex interaction between ncRNA and mRNA related to skin development and melanocyte development. The embryonic and postnatal development of skin provide a reference for further studies on the development mechanisms of ncRNA during pigmentation.


Subject(s)
Animals , Mice , Skin/embryology , Skin Pigmentation/genetics , Gene Expression Profiling , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Melanocytes , Cell Differentiation , Real-Time Polymerase Chain Reaction
17.
J Invertebr Pathol ; 168: 107272, 2019 11.
Article in English | MEDLINE | ID: mdl-31669539

ABSTRACT

Microsporidian spores contain a single polar filament that is coiled around the interior of the spore. Upon germination the polar tube (post-germination polar filament) is ejected by inversion into a host cell. The sporoplasm flows through the polar tube, directly infecting the cytoplasm of the cell. Various species of microsporidia display differences in the number of coils in the polar filament and in the amino acid sequence of the polar tube proteins (PTPs). Nosema pernyi is a lethal pathogen that causes microsporidiosis in the Chinese oak silkworm, Antheraea pernyi. In this study, we identified three PTPs in N. pernyi using RT-PCR and LC-MS/MS. Polar tube protein 3 was localized in the polar tube using immuno-histochemical staining and an immunofluorescence assay. Co-immunoprecipitation data and LC-MS/MS analysis revealed that some potential proteins, like immune related proteins in A. pernyi may interact with PTP3.


Subject(s)
Fungal Proteins/analysis , Nosema , Amino Acid Sequence , Animals , Antibodies, Fungal , Chromatography, Liquid , Fungal Proteins/chemistry , Fungal Proteins/genetics , Genes, Fungal , Host-Parasite Interactions , Immunohistochemistry , Immunoprecipitation , Insect Proteins/metabolism , Microsporidiosis/metabolism , Moths/metabolism , Moths/microbiology , Nosema/genetics , Nosema/metabolism , Nosema/ultrastructure , Phylogeny , Spores, Fungal/metabolism , Spores, Fungal/ultrastructure , Tandem Mass Spectrometry
18.
Org Biomol Chem ; 17(42): 9305-9312, 2019 10 30.
Article in English | MEDLINE | ID: mdl-31633136

ABSTRACT

The chiral primary amine catalyzed asymmetric Michael reaction of thiazolones and α,ß-unsaturated ketones was reported. Two different optimal catalytic systems were obtained corresponding to cyclic and linear α,ß-unsaturated ketones. By employing chiral primary amines as the catalysts and amino-acid derivatives as the additives, a variety of Michael adducts containing the scaffold of the thiazole ring were prepared in moderate to good yields and with excellent diastereo- and enantioselectivities (up to 95% yield, all up to >19/1 dr, up to 96% ee). The reaction was scaled up to obtain 1.73 grams of the Michael adduct with the maintenance of yield and stereoselectivity.

19.
Angew Chem Int Ed Engl ; 58(46): 16548-16552, 2019 11 11.
Article in English | MEDLINE | ID: mdl-31508880

ABSTRACT

A metal-free convergent paired electrolysis strategy to synthesize benzylic amines through direct arylation of tertiary amines and benzonitrile derivatives at room temperature has been developed. This TEMPO-mediated electrocatalytic reaction makes full use of both anodic oxidation and cathodic reduction without metals or stoichiometric oxidants, thus showing great potential and advantages for practical synthesis. This convergent paired electrolysis method provides a straightforward and powerful means to activate C-H bonds and realize cross-coupling with cathodically generated species.

20.
Food Chem ; 301: 125303, 2019 Dec 15.
Article in English | MEDLINE | ID: mdl-31387045

ABSTRACT

The effects of exogenous polyamines treatment on reactive oxygen species (ROS) metabolism in apricot fruits were systematically analyzed through the investigation of their curative and preventive effects on black spot disease. Results showed that 1.5 mM spermine (Spm), 1.5 mM spermidine (Spd) and 10 mM putrescine (Put) treatment significantly inhibited black spot development, additionally, the efficacy of this control was dependent upon the type of polyamines used and concentration level applied. Further studies have shown that exogenous polyamines treatments significantly improved production of O2- and H2O2, and increased the activities and gene expression levels of NADPH oxidase (NOX), super oxide dismutase (SOD), catalase (CAT) ascorbate peroxidase (AXP) and glutathione reductase (GR) in apricot fruit. Increased ascorbic acid (AsA) and reduced glutathione (GSH) content were also observed after exogenous polyamines treatment. These results have revealed that postharvest polyamines treatment effectively enhanced disease resistance through the maintenance of homeostasis in apricot fruits.


Subject(s)
Alternaria/pathogenicity , Fruit/drug effects , Plant Diseases/microbiology , Polyamines/pharmacology , Prunus armeniaca/drug effects , Ascorbate Peroxidases/metabolism , Catalase/metabolism , Disease Resistance/drug effects , Fruit/metabolism , Fruit/microbiology , Glutathione/metabolism , Glutathione Reductase/metabolism , Homeostasis/drug effects , Hydrogen Peroxide/metabolism , Oxidation-Reduction , Prunus armeniaca/metabolism , Prunus armeniaca/microbiology , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism
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