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1.
Small ; 20(21): e2309931, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38102094

RESUMO

Skin, characterized by its distinctive gradient structure and interwoven fibers, possesses remarkable mechanical properties and highly sensitive attributes, enabling it to detect an extensive range of stimuli. Inspired by these inherent qualities, a pioneering approach involving the crosslinking of macromolecules through in situ electron beam irradiation (EBI) is proposed to fabricate gradient ionogels. Such a design offers remarkable mechanical properties, including excellent tensile properties (>1000%), exceptional toughness (100 MJ m-3), fatigue resistance, a broad temperature range (-65-200°C), and a distinctive gradient modulus change. Moreover, the ionogel sensor exhibits an ultra-fast response time (60 ms) comparable to skin, an incredibly low detection limit (1 kPa), and an exceptionally wide detection range (1 kPa-1 MPa). The exceptional gradient ionogel material holds tremendous promise for applications in the field of smart sensors, presenting a distinct strategy for fabricating flexible gradient materials.

2.
Fish Shellfish Immunol ; 141: 109028, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37633345

RESUMO

Though Procambarus clarkii (red swamp crayfish) is a lower invertebrate, it has nonetheless developed a complex innate immune system. The crayfish farming industry has suffered considerable economic losses in recent years as a consequence of bacterial and viral diseases. Hence, perhaps the most effective ways to prevent microbial infections in P. clarkii are to examine and elucidate its innate immunity. The first step in the immune response is to recognize pathogen-associated molecular patterns (PAMPs) through pattern recognition receptors (PRRs). PRRs are expressed mainly on immune cell surfaces and recognize at least one PAMP. Thence, downstream immune responses are activated and pathogens are phagocytosed. To date, the PRRs identified in P. clarkii include Toll-like receptors (TLRs), lectins, fibrinogen-related proteins (FREPs), and ß-1,3-glucan-binding proteins (BGRPs). The present review addresses recent progress in research on PRRs and aims to provide guidance for improving immunity and preventing and treating infectious diseases in P. clarkii.


Assuntos
Astacoidea , Receptores de Reconhecimento de Padrão , Animais , Receptores de Reconhecimento de Padrão/genética , Imunidade Inata , Receptores Toll-Like/metabolismo , Bactérias/metabolismo
3.
Inorg Chem ; 62(23): 9217-9229, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37262344

RESUMO

Herein, we report the design and synthesis of Co-MOF-71/imidazole/SO3H as a novel porous catalyst with sulfonic acid tags. The structure and morphology of the catalyst were investigated using various techniques such as Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction, scanning electron microscopy (SEM), SEM elemental mapping, energy-dispersive X-ray spectroscopy, Barret-Joyner-Halenda, and N2 adsorption-desorption isotherms. Co-MOF-71/imidazole/SO3H was studied in the preparation of novel pyrazolo[3,4-b]pyridines under mild and green conditions via a cooperative vinylogous anomeric-based oxidation. A wide range of mono and bis pyrazolo[3,4-b]pyridines were synthesized with good to excellent yields (65-82%). A hot filtration test for the heterogeneous nature of the catalyst indicated the high stability of the prepared catalyst. The recyclability of Co-MOF-71/imidazole/SO3H is another advantage of the present methodology. The structures of the final products were confirmed using FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques.

4.
Org Biomol Chem ; 20(4): 847-851, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34994375

RESUMO

An efficient Pd-catalyzed direct C-H arylation of pyrrolo[1,2-a]quinoxalines with aryl iodides is described, providing a selective route toward a series of 1-arylated and 1,3-diarylated pyrrolo[1,2-a]quinoxalines in good yields. This method features a broad substrate scope, good functional group tolerance and gram-scale synthesis. Furthermore, the C3-thiocyanation of the arylated product is also achieved. We believe that these novel aryl-substituted pyrrolo [1,2-a]quinoxalines will have a variety of applications in organic synthesis and medicinal chemistry.

5.
Beilstein J Org Chem ; 16: 2920-2928, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335599

RESUMO

N-(Hetero)aryl-4,5-unsubstituted pyrroles were synthesized from (hetero)arylamines, 1,3-dicarbonyl compounds, and α-bromoacetaldehyde acetal by using aluminum(III) chloride as a Lewis acid catalyst through [1 + 2 + 2] annulation. This new versatile methodology provides a wide scope for the synthesis of different functional N-(hetero)aryl-4,5-unsubstituted pyrrole scaffolds, which can be further derived to access multisubstituted pyrrole-3-carboxamides. In the presence of 1.2 equiv of KI, a polysubstituted pyrazolo[3,4-b]pyridine derivative was also successfully synthesized.

6.
Beilstein J Org Chem ; 16: 2888-2902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299487

RESUMO

A waste biomass, sodium lignosulfonate, was treated with sodium 2-formylbenzenesulfonate, and the phenylaldehyde condensation product was then used as a robust supporting material to immobilize a copper species. The so-obtained catalyst was characterized by many physicochemical methods including FTIR, EA, FSEM, FTEM, XPS, and TG. This catalyst exhibited excellent catalytic activity in the synthesis of nitrogen-containing heterocycles such as tricyclic indoles bearing 3,4-fused seven-membered rings, 2­arylpyridines, aminonaphthalenes and 3-phenylisoquinolines. In addition, this catalyst showed to be recyclable and could be reused several times without significant loss in activity during the course of the reaction process.

7.
J Org Chem ; 84(5): 2941-2950, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30726672

RESUMO

2,3-Disubstituted benzofurans were synthesized from acrolein dimer and 1,3-dicarbonyl compounds by using N-bromosuccinimide as an oxidizing agent. The method was used to synthesize two commercial drug molecules, benzbromarone and amiodarone. The proposed mechanism of the reaction involves a N-bromosuccinimide (NBS)-assisted autotandem catalysis with Lewis acid catalyst. To proof the proposed mechanism, an intermediate was isolated successfully, which can be converted to 4,5,6,7-tetrahydrobenzofurans.

8.
J Org Chem ; 84(9): 5655-5666, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-30990706

RESUMO

1,2,4-Trisubstituted pyrroles were synthesized from enolizable aliphatic aldehydes and primary aliphatic amines by using iodine as the dual Lewis acid/mild oxidant. In the presence of 3.0 equiv of TBHP, enolizable α,ß-unsaturated aldehyde, for example, cocal reacted with aromatic primary amines to form C2-iodized N-arylpyrroles. An acetal-containing pyrrole was successfully prepared from 4-aminobutyraldehyde diethyl acetal, which can be converted easily to 5,6,7,8-tetrahydroindolizine derivatives.

9.
Org Biomol Chem ; 17(24): 5982-5989, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31166351

RESUMO

A straightforward access to tricyclic indoles bearing 3,4-fused seven-membered rings has been established by using 4-aminoindoles as 1,4-bisnucleophiles in three-component reactions. 1H-Azepino[4,3,2-cd]indoles, 4,6-dihydro-1H-azepino[4,3,2-cd]indoles and 1,3,4,6-tetrahydro-5H-azepino[4,3,2-cd]indol-5-ones could thus be synthesized in one pot in moderate to good yields. Beyond opening access to 3,4-fused tricyclic indoles, the use of easily accessible 4-aminoindoles as C,N-1,4-bisnucleophiles also provides a new platform to be used in a diversity-oriented synthesis strategy, fully displaying its benefits of maximizing molecular complexity and reaction diversity.


Assuntos
Indóis/química , Indóis/síntese química , Estrutura Molecular , Estereoisomerismo
10.
Chem Rec ; 17(2): 142-183, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27492258

RESUMO

Compounds containing oxygen, nitrogen, or sulfur atoms inside the rings are attracting much attention and interest due to their biological importance. In recent years, several methods for the synthesis of such molecules have been reported by using aldo-X bifunctional building blocks (AXB3 s) as substrates; these are a wide class of organic molecules that contain at least two reactive sites, among them, one aldehyde, acetal, or semiacetal group was involved. Because of the multiple reactivities, AXB3 s are widely used in the one-pot synthesis of biologically important heterocycles. This review summarizes the synthesis of important heterocycles by using AXB3 s as pivotal components in establishing multicomponent reactions, tandem reactions, and so forth. In many cases, the established reaction systems with AXB3 s were characterized by some green properties, such as easy access to the substrate, mild and environmentally benign conditions, and wide scope of the substrate.

11.
Chemistry ; 20(2): 549-58, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24307475

RESUMO

Lignosulfonate (LS) is an organic waste generated as a byproduct of the cooking process in sulfite pulping in the manufacture of paper. In this paper, LS was used as an anionic supporting material for immobilizing cationic species, which can then be used as heterogeneous catalysts in some organic transformations. With this strategy, three lignin-supported catalysts were prepared including 1) lignin-SO3 Sc(OTf)2 , 2) lignin-SO3 Cu(OTf), and 3) lignin-IL@NH2 (IL=ionic liquid). These solid materials were then examined in many organic transformations. It was finally found that, compared with its homogeneous counterpart as well as some other solid catalysts that are prepared by using different supports with the same metal or catalytically active species, the lignin-supported catalysts showed better performance in these reactions not only in terms of activity but also with regard to recyclability.


Assuntos
Resíduos Industriais , Lignina/análogos & derivados , Resíduos Sólidos , Catálise , Estudos de Viabilidade , Imidazóis/química , Líquidos Iônicos , Lignina/química , Mesilatos/química , Escândio/química
12.
J Org Chem ; 79(20): 9619-27, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25247719

RESUMO

Aldehydes were proved to be viable reagents for implementing alkenylation of α-oxoketene dithioacetals. AlCl3 was found to be the best catalyst. The established reaction opened an avenue to access densely substituted 1,3-butadiene derivatives. The obtained product bears multiple reactive sites that can be converted into various valuable molecules.


Assuntos
Acetais/química , Aldeídos/química , Alcenos/química , Compostos de Alumínio/química , Butadienos/síntese química , Cloretos/química , Indicadores e Reagentes/química , Compostos de Sulfidrila/síntese química , Cloreto de Alumínio , Butadienos/química , Catálise , Estrutura Molecular , Estereoisomerismo , Compostos de Sulfidrila/química
13.
Chem Soc Rev ; 42(24): 9550-70, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24056753

RESUMO

Biomass and waste exhibit great potential for replacing fossil resources in the production of chemicals. The search for alternative reaction media to replace petroleum-based solvents commonly used in chemical processes is an important objective of significant environmental consequence. Recently, bio-based derivatives have been either used entirely as green solvents or utilized as pivotal ingredients for the production of innovative solvents potentially less toxic and more bio-compatible. This review presents the background and classification of these new media and highlights recent advances in their use in various areas including organic synthesis, catalysis, biotransformation and separation. The greenness, advantages and limitations of these solvents are also discussed.


Assuntos
Biomassa , Química Verde/métodos , Solventes/química , Catálise
14.
Sci Rep ; 14(1): 14101, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38890358

RESUMO

The strategy of designing heterogeneous porous catalysts by a post-modification method is a smart strategy to increase the catalytic power of desired catalysts. Accordingly, in this report, metal-organic frameworks based on titanium with acetic acid pending were designed and synthesized via post-modification method. The structure of the target catalyst has been investigated using different techniques such as FT-IR, XRD, SEM, EDX, Mapping, and N2 adsorption/desorption (BET/the BJH) the correctness of its formation has been proven. The catalytic application of Ti-based MOFs functionalized with acetic acid was evaluated in the preparation of new spiropyrans, and the obtained results show that the catalytic performance is improved by this modification. The strategy of designing heterogeneous porous catalysts through post-modification methods presents a sophisticated approach to enhancing the catalytic efficacy of desired catalysts. In this context, our study focuses on the synthesis and characterization of metal-organic frameworks (MOFs) based on titanium, functionalized with acetic acid pendants, using a post-modification method. Various characterization techniques, including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), mapping, and N2 adsorption/desorption (BET/BJH), were employed to investigate the structure and composition of the synthesized catalyst. These techniques collectively confirmed the successful formation and structural integrity of the target catalyst. The structure of the synthesized products was confirmed by melting point, 1H-NMR and 13C-NMR and FT-IR techniques. Examining the general process of catalyst synthesis and its catalytic application shows that the mentioned modification is very useful for catalytic purposes. The presented catalyst was used in synthesis of a wide range of biologically active spiropyrans with good yields. The simultaneous presence of several biologically active cores in the synthesized products will highlight the biological properties of these compounds. The present study offers a promising insight into the rational design, synthesis, and application of task-specific porous catalysts, particularly in the context of synthesizing biologically active candidate molecules.

15.
Chem Commun (Camb) ; 60(44): 5715-5718, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38739371

RESUMO

Here, Selective C3-formylation of indole was achieved under mild conditions using a metal-organic framework (MOF) catalyst. The confined reaction space within the MOF pores effectively suppressed undesired side reactions and promoted the formation of the targeted product by controlling the reaction pathway. Density functional theory (DFT) calculations corroborated the experimental observations.

16.
Adv Sci (Weinh) ; : e2401562, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860673

RESUMO

Creating a diverse dipolar microenvironment around the active site is of great significance for the targeted induction of intermediate behaviors to achieve complicated chemical transformations. Herein, an efficient and general strategy is reported to construct hypercross-linked polymers (HCPs) equipped with tunable dipolar microenvironments by knitting arene monomers together with dipolar functional groups into porous network skeletons. Benefiting from the electron beam irradiation modification technique, the catalytic sites are anchored in an efficient way in the vicinity of the microenvironment, which effectively facilitates the processing of the reactants delivered to the catalytic sites. By varying the composition of the microenvironment scaffold structure, the contact and interaction behavior with the reaction participants can be tuned, thereby affecting the catalytic activity and selectivity. As a result, the framework catalysts produced in this way exhibit excellent catalytic performance in the synthesis of glycinate esters and indole derivatives. This manipulation is reminiscent of enzymatic catalysis, which adjusts the internal polarity environment and controls the output of products by altering the scaffold structure.

17.
Dalton Trans ; 52(17): 5742-5759, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37038895

RESUMO

Recently, doping metals into graphitic carbon nitride (g-C3N4) is considered for environmental applications and organic reactions. In this study, we used ferrocene as a source of Fe3+ to dope iron onto g-C3N4. The scaffold of the internal electric field is presented as an impressive strategy to increase photocatalytic activities. Fe3+ was doped onto graphitic carbon nitride (FeIII/g-C3N4) by the calcination method, which was well characterized by FT-IR, Raman, XRF, XRD, XPS, UV-visible DRS, photo-luminescence (PL), photocurrent, SEM, HR-TEM, EDX, BET, EIS, and cyclic voltammetry analyses. The synthesis of benzimidazole derivatives as pharmaceutically active compounds was introduced by using a suitable method under mild reaction conditions without using a base, oxidant, and other reagents or additives. The modification by using iron had a considerable effect on the optical and electronic characteristics in contrast to g-C3N4. The nanocomposite FeIII/g-C3N4 could be employed as a multifunctional photocatalyst to perform the tandem process, oxidation of toluene, and then cyclization with o-phenylenediamines to prepare benzimidazoles under visible light conditions. The existence of the dynamic equilibrium of Fe3+/Fe2+ helped in significantly improving the activity. By changing the reaction conditions and different control experiments as well as Mott-Schottky plot analysis, the superoxide ion (O2˙-) can be obtained as the reactive species in this reaction. The photocatalytic activity of FeIII/g-C3N4 for this one-pot reaction is also investigated in detail.

18.
ChemSusChem ; 16(3): e202201755, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36282629

RESUMO

In this study, an efficient method for the separation of 5-hydroxymethylfurfural by the specific adsorption of dimethyl sulfoxide (DMSO) with cellulose microgels fabricated by electron beam irradiation was developed. The cellulose microgel was recovered and reused although this was accompanied by a decrease in the separation efficiency. A series of characterizations, including ultraviolet and infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and swelling ability tests, were performed to determine the adsorption behavior of the chemical structures of the microgel toward DMSO. The results showed that after the first run, the chemical structure of the recovered microgel did not change significantly. Electron-beam etching played a pivotal role in conferring a special capacity for enriching DMSO in its matrix on the microgel.

19.
ChemSusChem ; 16(3): e202300050, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36703570

RESUMO

Invited for this month's cover is the groups of Jiang Huang and Yanlong Gu at Huazhong University of Science and Technology. The image shows a new method for the separation of dimethyl sulfoxide from a reaction solution of synthesizing 5-hydroxymethylfurfural by means of using a cellulose microgel fabricated by electron beam irradiation as a bio-based absorbant. The Research Article itself is available at 10.1002/cssc.202201755.

20.
ACS Omega ; 8(28): 25303-25315, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483221

RESUMO

Combining two different metals for the synthesis of a metal-organic framework (MOF) is a smart strategy for the architecture of new porous materials. Herein, a bimetal-organic framework (bimetal-MOFs) based on Fe and Co metals was synthesized. Then, phosphorous acid tags were decorated on bimetal-MOFs via a postmodification method as a new porous acidic functionalized catalyst. This catalyst was used for the synthesis of pyrazolo[4,3-e]pyridine derivatives as suitable drug candidates. The present study provides new insights into the architecture of novel porous heterogeneous catalysts based on a bimetal-organic framework (bimetal-MOFs). The type of final structures of catalyst and pyrazolo[4,3-e]pyridine derivatives were determined using different techniques such as fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), SEM-elemental mapping, N2 adsorption-desorption isotherm, Barrett-Joyner-Halenda (BJH), thermogravimetry/differential thermal analysis (TG/DTA), 1H NMR, and 13C NMR.

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