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2.
Biomed Microdevices ; 26(3): 28, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38825594

RESUMO

Microfluidic-based point-of-care diagnostics offer several unique advantages over existing bioanalytical solutions, such as automation, miniaturisation, and integration of sensors to rapidly detect on-site specific biomarkers. It is important to highlight that a microfluidic POC system needs to perform a number of steps, including sample preparation, nucleic acid extraction, amplification, and detection. Each of these stages involves mixing and elution to go from sample to result. To address these complex sample preparation procedures, a vast number of different approaches have been developed to solve the problem of reagent storage and delivery. However, to date, no universal method has been proposed that can be applied as a working solution for all cases. Herein, both current self-contained (stored within the chip) and off-chip (stored in a separate device and brought together at the point of use) are reviewed, and their merits and limitations are discussed. This review focuses on reagent storage devices that could be integrated with microfluidic devices, discussing further issues or merits of these storage solutions in two different sections: direct on-chip storage and external storage with their application devices. Furthermore, the different microvalves and micropumps are considered to provide guidelines for designing appropriate integrated microfluidic point-of-care devices.


Assuntos
Dispositivos Lab-On-A-Chip , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Indicadores e Reagentes/química , Desenho de Equipamento
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 343-345, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863106

RESUMO

From the perspective of the performance evaluation, concerns of the range of pathogens, establishment of enterprise reference material, reaction system study and analytical performances evaluation of central nervous system infection pathogen metagenome sequencing reagent are briefly described, including study methods and quality control requirements. This study is intended to increase the research and development efficiency of products, and contribute to the development of associated industry.


Assuntos
Infecções do Sistema Nervoso Central , Metagenoma , Infecções do Sistema Nervoso Central/microbiologia , Controle de Qualidade , Indicadores e Reagentes
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 339-342, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863105

RESUMO

As an important part of the Big Health Industry, in vitro diagnostic(IVD) reagents play a vital role in the prevention, diagnosis and treatment of diseases. In recent years, especially after the novel coronavirus infection, IVD industry has developed rapidly in China, but it still cannot meet the needs of clinical use. By conducting desk research, expert interview, manufacturer survey and hospital survey, this study analyzed the development status of IVD industry in Shanghai, summarized the problems encountered in the high-quality development from the aspects of raw materials, innovation ability, and clinical trials, etc., and proposed recommendations for promoting the high-quality innovation and development of IVD industry in Shanghai.


Assuntos
Indicadores e Reagentes , China , Humanos , COVID-19
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 315-318, 2024 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-38863100

RESUMO

The management of in vitro diagnostic (IVD) reagents in hospitals often faces issues such as the lack of a unified coding system, unclear consumption patterns, and unknown cost-to-income ratios. It is necessary to employ information systems to achieve comprehensive, detailed, and traceable management of IVD reagents. An information management system for IVD reagents based on unique coding is introduced, which integrates admission, acceptance, and consumption processes through unique codes. The system calculates the income per experimental item based on the consumption of IVD reagents and the charge for each experimental item. The system enhances the efficiency of the IVD reagent supply chain management and promotes detailed oversight of IVD reagent usage.


Assuntos
Indicadores e Reagentes , Sistemas de Informação Administrativa , Administração de Materiais no Hospital
6.
J Forensic Sci ; 69(4): 1429-1440, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880998

RESUMO

To establish the correlation between thermal conditions imposed on bloodstains and visualizing effect of enhancement techniques, infrared photography and four chemical enhancement reagents were used to visualize bloodstains following thermal exposure. A black tile was selected as the substrate to intensify the visualization challenge, with a Cone Calorimeter serving as the standardized heating source to control thermal conditions. Compared with standard photography, infrared photography is proven to be a valuable complement to chemical reagents, showing significant advantages in visualizing bloodstains after thermal exposure. However, it is worth noting that infrared image fell short of standard image when bloodstains displayed raised, embossed morphology or when bloodstains almost disappeared under specific conditions. The enhancement effectiveness was found to be strongly correlated with thermal conditions imposed on bloodstains, and the morphology evolution of bloodstains during heating affected the chemical enhancement effect additionally, especially when the bulge morphology was formed, and it was observed that reagents were more effective after removing the dense shell of the bulge. Among the four selected chemical enhancement reagents, fluorescein performed exceptionally well, maintaining its effectiveness even for bloodstains heated at 641°C for 10 min. TMB demonstrated its visualizing ability for bloodstains heated at 396°C for 5 min and heated at 310°C for 20 min. BLUESTAR® followed afterwards, while luminol performed worst. The correlation between thermal conditions imposed on bloodstains and the corresponding visualizing effectiveness of enhancement techniques provides important references for detecting bloodstains at fire scenes.


Assuntos
Manchas de Sangue , Temperatura Alta , Fotografação , Humanos , Raios Infravermelhos , Luminol , Fluoresceína , Indicadores e Reagentes , Calorimetria , Corantes Fluorescentes , Medicina Legal/métodos , Substâncias Luminescentes
7.
J Agric Food Chem ; 72(26): 14601-14609, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38900413

RESUMO

Although γ-methacryloxypropyltrimethoxysilane (MPS) was proved to be an effective reagent for improving the dimensional stability of wood, a bottleneck in ASE value (around 50%) existed. The reason was that MPS with low polarity opened few hydrogen bonds in the amorphous region of cellulose, while these hydrogen bonds could be reopened by water. Therefore, citric acid (CA) is chosen to cooperate with MPS to further enhance the dimensional stability of wood. In this paper, MPS and CA were used to modify wood individually (MW and CW) or with different combinations, that is, one-step modification (M/CW) and two-step modification with MPS first (M-CW) or CA first (C-MW). CA and MPS concentrations were optimized at 5 wt%. The ASE value for M/CW was only 25.74% at a weight percent gain (WPG) of 6.43%, which was only 0.6 times to MW or 0.7 times to CW. For M-CW, the ASE value gradually decreased with the soaking cycles, from 65.64% at a WPG of 9.05% to 51.20%. The C-MW had the best dimensional stability, with the ASE value 75.35% at a WPG of 11.50%. Although it decreased during the first soaking cycle, it stabilized at 62.20% at last. SEM and EDS images showed that the polymer mainly distributed in cell walls and few in cell lumen in C-MW. Thus, the enhanced dimensional stability of C-MW could be explained by CA opening the hydrogen bonds in the amorphous region of cellulose first, which provided more binding sites for MPS.


Assuntos
Parede Celular , Celulose , Madeira , Madeira/química , Celulose/química , Parede Celular/química , Ácido Cítrico/química , Ligação de Hidrogênio , Silanos/química , Indicadores e Reagentes/química
8.
Nature ; 631(8020): 319-327, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898275

RESUMO

Naturally occurring (native) sugars and carbohydrates contain numerous hydroxyl groups of similar reactivity1,2. Chemists, therefore, rely typically on laborious, multi-step protecting-group strategies3 to convert these renewable feedstocks into reagents (glycosyl donors) to make glycans. The direct transformation of native sugars to complex saccharides remains a notable challenge. Here we describe a photoinduced approach to achieve site- and stereoselective chemical glycosylation from widely available native sugar building blocks, which through homolytic (one-electron) chemistry bypasses unnecessary hydroxyl group masking and manipulation. This process is reminiscent of nature in its regiocontrolled generation of a transient glycosyl donor, followed by radical-based cross-coupling with electrophiles on activation with light. Through selective anomeric functionalization of mono- and oligosaccharides, this protecting-group-free 'cap and glycosylate' approach offers straightforward access to a wide array of metabolically robust glycosyl compounds. Owing to its biocompatibility, the method was extended to the direct post-translational glycosylation of proteins.


Assuntos
Técnicas de Química Sintética , Oligossacarídeos , Açúcares , Radicais Livres/química , Radicais Livres/metabolismo , Glicosilação/efeitos da radiação , Indicadores e Reagentes/química , Luz , Oligossacarídeos/síntese química , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Oligossacarídeos/efeitos da radiação , Estereoisomerismo , Açúcares/síntese química , Açúcares/química , Açúcares/metabolismo , Açúcares/efeitos da radiação
9.
Anal Methods ; 16(24): 3810-3814, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38855885

RESUMO

A cysteine-based fluorous trapping reagent, Rf8CYS, was developed. Rf8CYS formed adducts with soft and hard electrophilic reactive metabolites. These fluorous-tagged adducts were purified via both fluorous solid-phase extraction and the direct injection method. The highly sensitive mass spectrometric detection of an unprecedented adduct of the ticlopidine metabolite was realized.


Assuntos
Cisteína , Extração em Fase Sólida , Cisteína/química , Cisteína/metabolismo , Cisteína/análise , Extração em Fase Sólida/métodos , Indicadores e Reagentes/química , Espectrometria de Massas/métodos , Humanos
10.
Nature ; 629(8010): 98-104, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693411

RESUMO

Photobiocatalysis-where light is used to expand the reactivity of an enzyme-has recently emerged as a powerful strategy to develop chemistries that are new to nature. These systems have shown potential in asymmetric radical reactions that have long eluded small-molecule catalysts1. So far, unnatural photobiocatalytic reactions are limited to overall reductive and redox-neutral processes2-9. Here we report photobiocatalytic asymmetric sp3-sp3 oxidative cross-coupling between organoboron reagents and amino acids. This reaction requires the cooperative use of engineered pyridoxal biocatalysts, photoredox catalysts and an oxidizing agent. We repurpose a family of pyridoxal-5'-phosphate-dependent enzymes, threonine aldolases10-12, for the α-C-H functionalization of glycine and α-branched amino acid substrates by a radical mechanism, giving rise to a range of α-tri- and tetrasubstituted non-canonical amino acids 13-15 possessing up to two contiguous stereocentres. Directed evolution of pyridoxal radical enzymes allowed primary and secondary radical precursors, including benzyl, allyl and alkylboron reagents, to be coupled in an enantio- and diastereocontrolled fashion. Cooperative photoredox-pyridoxal biocatalysis provides a platform for sp3-sp3 oxidative coupling16, permitting the stereoselective, intermolecular free-radical transformations that are unknown to chemistry or biology.


Assuntos
Aminoácidos , Biocatálise , Acoplamento Oxidativo , Processos Fotoquímicos , Aminoácidos/biossíntese , Aminoácidos/química , Aminoácidos/metabolismo , Biocatálise/efeitos da radiação , Evolução Molecular Direcionada , Radicais Livres/química , Radicais Livres/metabolismo , Glicina/química , Glicina/metabolismo , Glicina Hidroximetiltransferase/metabolismo , Glicina Hidroximetiltransferase/química , Indicadores e Reagentes , Luz , Acoplamento Oxidativo/efeitos da radiação , Fosfato de Piridoxal/metabolismo , Estereoisomerismo , Aminoácidos de Cadeia Ramificada/química , Aminoácidos de Cadeia Ramificada/metabolismo
11.
Org Biomol Chem ; 22(22): 4420-4435, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775347

RESUMO

Over past decades, chiral amides and peptides have emerged as powerful and versatile compounds due to their various biological activities and interesting molecular architectures. Although some chiral condensation reagents have been applied successfully for their synthesis, the introduction of racemization-free methods of amino acid activation have shown lots of advantages in terms of their low cost and low toxicity. In this review, advancements in amide and peptide synthesis using racemization-free coupling reagents over the last 10 years are summarized. Various racemization-free coupling reagents have been applied in the synthesis of enantioselective amides and peptides, including ynamides, allenones, HSi[OCH(CF3)2]3, Ta(OMe)5, Nb(OEt)5, Ta(OEt)5, TCFH-NMI, water-removable ynamides, DBAA, DATB, o-NosylOXY, TCBOXY, Boc-Oxyma, NDTP, 9-silafluorenyl dichlorides, the Mukaiyama reagent, EDC and T3P. The racemization-free reagents described in this review provide an alternative greener option for the asymmetric synthesis of chiral amides and peptides. We hope that this review will inspire further studies and developments in this field.


Assuntos
Amidas , Peptídeos , Amidas/química , Amidas/síntese química , Peptídeos/química , Peptídeos/síntese química , Estereoisomerismo , Técnicas de Química Sintética/métodos , Indicadores e Reagentes/química , Estrutura Molecular
12.
Vet Immunol Immunopathol ; 272: 110769, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703558

RESUMO

There are extensive immunological reagents available for laboratory rodents and humans. However, for veterinary species there is a need for expansion of immunological toolkits, with this especially evident for marine mammals, such as cetaceans. In addition to their use in a research setting, immune assays could be employed to monitor the health status of cetaceans and serve as an adjunct to available diagnostic tests. Such development of specific and sensitive immune assays will enhance the proper care and stewardship of wild and managed cetacean populations. Our goal is to provide immune reagents and immune assays for the research community, clinicians, and others involved in care of bottlenose dolphins. This review will provide an update on our development of a bottlenose dolphin immunological toolkit. The future availability and continued development of these reagents is critical for improving wild and managed bottlenose dolphin population health through enhanced assessment of their responses to alterations in the marine environment, including pathogens, and improve our ability to monitor their status following vaccination.


Assuntos
Golfinho Nariz-de-Garrafa , Técnicas Imunológicas , Indicadores e Reagentes , Animais , Golfinho Nariz-de-Garrafa/imunologia , Técnicas Imunológicas/veterinária
13.
Top Curr Chem (Cham) ; 382(2): 15, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703255

RESUMO

Aligned with the increasing importance of bioorthogonal chemistry has been an increasing demand for more potent, affordable, multifunctional, and programmable bioorthogonal reagents. More advanced synthetic chemistry techniques, including transition-metal-catalyzed cross-coupling reactions, C-H activation, photoinduced chemistry, and continuous flow chemistry, have been employed in synthesizing novel bioorthogonal reagents for universal purposes. We discuss herein recent developments regarding the synthesis of popular bioorthogonal reagents, with a focus on s-tetrazines, 1,2,4-triazines, trans-cyclooctenes, cyclooctynes, hetero-cycloheptynes, and -trans-cycloheptenes. This review aims to summarize and discuss the most representative synthetic approaches of these reagents and their derivatives that are useful in bioorthogonal chemistry. The preparation of these molecules and their derivatives utilizes both classical approaches as well as the latest organic chemistry methodologies.


Assuntos
Ciclo-Octanos , Triazinas , Triazinas/química , Triazinas/síntese química , Ciclo-Octanos/química , Ciclo-Octanos/síntese química , Alcinos/química , Alcinos/síntese química , Catálise , Indicadores e Reagentes/química , Estrutura Molecular
14.
Angew Chem Int Ed Engl ; 63(30): e202405344, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38753429

RESUMO

Peptide cyclization has dramatic effects on a variety of important properties, enhancing metabolic stability, limiting conformational flexibility, and altering cellular entry and intracellular localization. The hydrophilic, polyfunctional nature of peptides creates chemoselectivity challenges in macrocyclization, especially for natural sequences without biorthogonal handles. Herein, we describe a gaseous sulfonyl chloride derived reagent that achieves amine-amine, amine-phenol, and amine-aniline crosslinking through a minimalist linchpin strategy that affords macrocyclic urea or carbamate products. The cyclization reaction is metal-mediated and involves a novel application of sulfine species that remains unexplored in aqueous or biological contexts. The aqueous method delivers unique cyclic or bicyclic topologies directly from a variety of natural bioactive peptides without the need for protecting-group strategies.


Assuntos
Aminas , Ciclização , Aminas/química , Peptídeos/química , Gases/química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/síntese química , Indicadores e Reagentes/química
15.
Forensic Sci Int ; 358: 112018, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581824

RESUMO

A number of solvents, (Solstice PF, Opteon SF33 and Amolea AS-300), are compared to the recommended carrier solvent of HFE7100 for the ninhydrin and 1,2-indandione formulations. As the supply of HFE7100 will cease by the end of 2025, suitable alternatives are required in the short-term to ensure the detection of latent fingermarks on porous surfaces is still effective. Although these solvents, with the exception of Amolea AS-300, are classified as per- and polyfluoroalkyl substances (PFAS); they are not classed as hazardous. The alternatives in this study have a low global warming potential and atmospheric lifetime and are volatile, non-flammable and non-ozone depleting, in addition to other desirable properties such as a high wetting-index. During Phase 2 trials with deposited fingermarks, HFE7100 provided the best performing results followed by Opteon SF33, Solstice PF and Amolea AS-300. A significant difference with a negligible effect size was observed for ninhydrin formulations (p-value 0.00179; ε2 0.00418) while a significant difference with a weak effect size was observed for 1,2-indanedione formulations (p-value 2.095 ×10-10; ε2 0.0167). Furthermore, HFE7100 provided the least ink diffusion and the brightest 1,2-indanedione luminosity (significant difference with a moderate effect size p-value 1.772 ×10-13; ε2 0.0434) but the HFE formulation turned cloudy more quickly and needed regular replacements. Phase 3 pseudo-operational trials of 100 porous items followed a similar trend whereby HFE7100 formulations detected the highest number of marks followed by Opteon SF33 and Solstice PF. Although HFE7100 is still the best performing carrier solvent, this study demonstrates that, in the short-term, Opteon SF33 and Solstice PF may have potential as non-flammable replacement carrier solvents while developing the long-term goal of solvent-less methods.


Assuntos
Dermatoglifia , Indanos , Indicadores e Reagentes , Ninidrina , Solventes , Humanos , Solventes/química , Indanos/química
16.
Anal Chem ; 96(15): 5815-5823, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38575144

RESUMO

Microfluidic techniques are widely applied in biomolecular analysis and disease diagnostic assays. While the volume of the sample that is directly used in such assays is often only femto-to microliters, the "dead volume" of solutions supplied in syringes and tubing can be much larger, even up to milliliters, increasing overall reagent use and making analysis significantly more expensive. To reduce the difficulty and cost, we designed a new chip using a low volume solution for analysis and applied it to obtain real-time data for protein-protein interaction measurements. The chip takes advantage of air/aqueous two-phase droplet flow, on-chip rapid mixing within milliseconds, and a droplet capture method, that ultimately requires only 2 µL of reagent solution. The interaction is analyzed by particle diffusometry, a nonintrusive and precise optical detection method to analyze the properties of microparticle diffusion in solution. Herein, we demonstrate on-chip characterization of human immunodeficiency virus p24 antibody-antigen protein binding kinetics imaged via fluorescence microscopy and analyzed by PD. The measured kon and koff are 1 × 106 M-1 s-1 and 3.3 × 10-4 s-1, respectively, and agree with independent measurement via biolayer interferometry and previously calculated p24-antibody binding kinetics. This new microfluidic chip and the protein-protein interaction analysis method can also be applied in other fields that require low-volume solutions to perform accurate measurement, analysis, and detection.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Humanos , Cinética , Difusão , Indicadores e Reagentes , Técnicas Analíticas Microfluídicas/métodos
18.
Talanta ; 275: 126084, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608344

RESUMO

The 5-nitro-2-furaldehyde (5-NF) is an aldehyde aromatic organic compound that has been envisaged as an alternative marker for detecting nitrofurazone treatment abuse and to avoid the false positive results induced by the semicarbazide. Analyzing 5-NF presents challenges, and its derivatization reaction with hydrazine reagents is required to enhance the capability of its detection and its identification. This study aims at developping an analytical method for 5-NF determination in trout muscle samples based on chemical derivatization prior to analysis by liquid chromatography-tandem mass spectrometry. Four commercially available hydrazine reagents, namely: N,N-Dimethylhydrazine (DMH), 4-Hydrazinobenzoic acid (HBA), 2,4-Dichlorophenylhydrazine (2,4-DCPH) and 2,6-Dichlorophenylhydrazine (2,6-DCPH) were proposed for the first time as derivatizing reagents in the analysis of 5-NF. The derivatization reaction was simultaneously performed along with the extraction method in acidic condition using ultrasonic assistance and followed by liquid extraction using acetonitrile. The efficiency of the chemical reaction with 5-NF was examined and the reaction conditions including the concentration of hydrochloric acid, pH, temperature, reaction time and the concentration of the derivatizing reagents were optimized. Experiments with fortified samples demonstrated that 2,4-DCPH derivatizing reagent at 20 mM for 20 min of ultrasonic treatment under acidic condition (pH 4) gave an effective sample derivatization method for 5-NF analysis. Under the optimized conditions, the calibration curves were linear from 0.25 to 2 µg kg-1 with coefficient of determination >0.99. The recoveries ranged from 89 % to 116 % and precision was less than 13 %. The limit of detection and quantification were 0.1 and 0.2 µg kg-1, respectively.


Assuntos
Músculos , Espectrometria de Massas em Tandem , Truta , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Músculos/química , Furaldeído/análogos & derivados , Furaldeído/análise , Furaldeído/química , Limite de Detecção , Indicadores e Reagentes/química , Hidrazinas/química
19.
J Cosmet Dermatol ; 23(6): 2231-2239, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38576192

RESUMO

BACKGROUND: Pigment Red 53 is a dangerous synthetic dye that is often added to cosmetics, even though its use in cosmetic products has been prohibited because of possible impacts on health. Faster and more sensitive detection of Pigment Red 53 is needed for onsite analysis to protect the community from illegal cosmetics that contain the dye. Indicator color charts are a kind of analytical method that can be used to detect Pigment Red 53 in cosmetic products, including lipstick, rouge, and eyeshadow. Such charts are practical, fast, and can be used for onsite analysis. METHODS: In this study, an indicator for Pigment Red 53 detection was obtained through a reagent reaction that caused a specific color change. An indicator color chart was then produced by setting out in paper form the series of colors which resulted from the reaction of specific chemical reagents and Pigment Red 53 solutions at concentrations of 10, 20, 40, 60, 80, and 100 ppm. RESULTS: The testing results showed that the indicator color chart may be used as an initial screening method for the detection of Pigment Red 53 in cosmetic products with a detectable minimum concentration of 10 ppm. Out of nine samples, only one (Eyeshadow 3) tested positive for Pigment Red 53. Further analysis was carried out on the indicator color chart and the results showed good agreement with TLC and UV-Vis spectrophotometry methods. CONCLUSION: The results reported in this paper demonstrate that the indicator color chart is a good prospective method for onsite analysis to detect Pigment Red 53 in cosmetic samples, with a lower detection limit compared to polymer-based indicators.


Assuntos
Corantes , Cosméticos , Cosméticos/química , Cosméticos/análise , Indonésia , Humanos , Corantes/análise , Cor , Colorimetria/métodos , Compostos Azo/análise , Compostos Azo/química , Indicadores e Reagentes/química
20.
Top Curr Chem (Cham) ; 382(2): 12, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589598

RESUMO

Organoselenium compounds have been the subject of extensive research since the discovery of the biologically active compound ebselen. Ebselen has recently been found to show activity against the main protease of the virus responsible for COVID-19. Other organoselenium compounds are also well-known for their diverse biological activities, with such compounds exhibiting interesting physical properties relevant to the fields of electronics, materials, and polymer chemistry. In addition, the incorporation of selenium into various organic molecules has garnered significant attention due to the potential of selenium to enhance the biological activity of these molecules, particularly in conjunction with bioactive heterocycles. Iodine and iodine-based reagents play a prominent role in the synthesis of organoselenium compounds, being valued for their cost-effectiveness, non-toxicity, and ease of handling. These reagents efficiently selenylate a broad range of organic substrates, encompassing alkenes, alkynes, and cyclic, aromatic, and heterocyclic molecules. They serve as catalysts, additives, inducers, and oxidizing agents, facilitating the introduction of different functional groups at alternate positions in the molecules, thereby allowing for regioselective and stereoselective approaches. Specific iodine reagents and their combinations can be tailored to follow the desired reaction pathways. Here, we present a comprehensive review of the progress in the selenylation of organic molecules using iodine reagents over the past decade, with a focus on reaction patterns, solvent effects, heating, microwave, and ultrasonic conditions. Detailed discussions on mechanistic aspects, such as electrophilic, nucleophilic, radical, electrochemical, and ring expansion reactions via selenylation, multiselenylation, and difunctionalization, are included. The review also highlights the formation of various cyclic, heterocyclic, and heteroarenes resulting from the in situ generation of selenium intermediates, encompassing cyclic ketones, cyclic ethers, cyclic lactones, selenophenes, chromones, pyrazolines, pyrrolidines, piperidines, indolines, oxazolines, isooxazolines, lactones, dihydrofurans, and isoxazolidines. To enhance the reader's interest, the review is structured into different sections covering the selenylation of aliphatic sp2/sp carbon and cyclic sp2 carbon, and then is further subdivided into various heterocyclic molecules.


Assuntos
Iodo , Isoindóis , Compostos Organosselênicos , Selênio , Iodo/química , Indicadores e Reagentes , Compostos Organosselênicos/química , Lactonas/química , Carbono
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