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1.
Small ; 20(20): e2307129, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126615

RESUMO

Organic luminescent materials are indispensable in optoelectronic displays and solid-state luminescence applications. Compared with single-component, multi-component crystalline materials can improve optoelectronic characteristics. This work forms a series of full-spectrum tunable luminescent charge-transfer (CT) cocrystals ranging from 400 to 800 nm through intermolecular collaborative self-assembly. What is even more interesting is that o-TCP-Cor(x)-Pe(1-x), p-TCP-Cor(x)-Pe(1-x), and o-TCP-AN(x)-TP(1-x) alloys are prepared based on cocrystals by doping strategies, which correspondingly achieve the stepless color change from blue (CIE [0.22, 0.44]) to green (CIE [0.16, 0.14]), from green (CIE [0.27, 0.56]) to orange (CIE [0.58, 0.42]), from yellow (CIE [0.40, 0.57]) to red (CIE [0.65, 0.35]). The work provides an efficient method for precisely synthesizing new luminescent organic semiconductor materials and lays a solid foundation for developing advanced organic solid-state displays.

2.
Chemistry ; : e202402995, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305150

RESUMO

The synthesis of α-tertiary amino acids (ATAAs), which are pivotal components in natural metabolism and pharmaceutical innovation, continues to attract significant research interest. Despite substantial advancements, the pursuit of a facile, versatile, and resource-efficient methodology remains an area of active development. In this work, we introduce a visible light-triggered three-component reaction involving readily available nitrosoarenes, N-acyl pyrazoles, and allyl or (bromomethyl)benzenes under mild conditions. This approach enables the straightforward assembly of a wide array of ATAA derivatives (41 examples) in commendably high yields (up to 89%). Mechanistic investigations elucidate that the reaction proceeds through a dehydration condensation between nitrosoarenes and N-acyl pyrazoles to generate ketimine intermediates. This is followed by a light-driven halogen atom transfer (XAT) process and a radical addition, culminating in the formation of the desired products. The approach showcases excellent functional group compatibility and late-stage derivatization potential, offering new insights and avenues for the synthesis of ATAA analogs.

3.
Mol Divers ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38769226

RESUMO

Pyrrole is an essential chemical with considerable relevance as a pharmaceutical framework for many biologically necessary medications. The growing demand for biologically active compounds calls for a simple one-pot method for generating novel pyrrole derivatives. Nots surprisingly, several multicomponent reactions (MCRs) aim to synthesize pyrrole derivatives. However, this review presents the three-component synthesis of pyrrole derivatives, highlighting the significance of multicomponent reaction in synthesizing eclectic multi-functionalised pyrrole covering the selected literature on the three-component synthesis of substituted pyrrole from 2016 to late 2023. Furthermore, this article classifies the reactions based on the starting material with functional groups involved in the pyrrole ring formation.

4.
Mol Divers ; 28(1): 73-83, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36604370

RESUMO

Three-component reaction between trialkyl phosphites, dialkyl acetylenedicarboxylates and aromatic amines afforded ß-aminoalkylphosphonate derivatives. Similar reaction between trialkyl phosphites, dialkyl acetylenedicarboxylates and dinitrophenylhydrazine afforded ß-hydrazinooalkylphosphonate derivatives. This method includes both the C-N and C-P bond formation in a one pot and single synthetic step in neutral and simple reaction conditions. All reactions were conducted in CH2Cl2 as solvent at room temperature without using any catalyst, and the stable products were obtained in high yields. The structures of all products were proved by 1H, 13C and 31P NMR and IR spectral and elemental analysis data.


Assuntos
Fosfitos , Fosfitos/química , Aminas , Espectroscopia de Ressonância Magnética , Catálise , Hidrazinas
5.
Mol Divers ; 28(1): 159-169, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37046046

RESUMO

Herein, a new type of pyranocoumarin derivatives 7-alkyl or aryl-6H,7H-benzo[f]chromeno[4,3-b] chromen-6-ones (2a-h) was developed via three component reaction of 4-hydroxy coumarin, ß-naphthol and aliphatic/aryl aldehydes using 25 mol% of N,N-disulfopiperidinium bisulfate [DSPP][HSO4] as homogeneous recyclable Brönsted acidic ionic liquid catalyst in EtOAc under reflux to produce excellent yields (89-97%) of the products within 2-4 h reaction. In neat condition, the same reaction required 4.5 h to produce 90% yield of model product (2d) at 100 ℃, which took only 2.5 h to yield 97% of the same product in EtOAc under reflux temperature.


Assuntos
Líquidos Iônicos , Aldeídos , Catálise
6.
Arch Pharm (Weinheim) ; 357(3): e2300632, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38150663

RESUMO

Herein, we outline a highly efficient PEG-4000-mediated one-pot three-component reaction for the synthesis of 3-imidazolyl indole clubbed 1,2,3-triazole derivatives (5a-r) at up to 96% yield as antiproliferative agents. This three-component protocol offers the advantages of an environmentally benign reaction, excellent yield, quick response time, and operational simplicity triggered by the copper catalyst under microwave irradiation. All the synthesized compounds were tested for antiproliferative activity against six human solid tumor cell lines, that is, A549 and SW1573 (nonsmall cell lung), HBL100 and T-47D (breast), HeLa (cervix), and WiDr (colon). Among them, six compounds, 5g-j, 5m, and 5p, demonstrated effective antiproliferative action with GI50 values under 10 µM. Furthermore, density functional theory (DFT) calculations were performed for all the synthesized molecules through geometry optimizations, frontier molecular orbital approach, and molecular electrostatic potential (MESP). The theoretical DFT calculation was performed using the DFT/B3LYP/6-31+G (d,p) basis set. Moreover, the biological reactivity of all the representative synthesized molecules was compared with the theoretically calculated quantum chemical descriptors and MESP 3D plots. We also investigated the drug-likeness characteristic and absorption, distribution, metabolism, excretion, and toxicity (ADMET) prediction. In general, our approach enables environmentally friendly access to 3-imidazolyl indole clubbed 1,2,3-triazole derivatives as prospective antiproliferative agents.


Assuntos
Antineoplásicos , Micro-Ondas , Feminino , Humanos , Teoria da Densidade Funcional , Estudos Prospectivos , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Células HeLa , Indóis/farmacologia
7.
Sensors (Basel) ; 24(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39204982

RESUMO

A digitizer is considered one of the fundamental components of an earthquake monitoring system. In this paper, we design and implement a high accuracy seismic digitizer. The implemented digitizer consists of several blocks, i.e., the analog-to-digital converter (ADC), GPS receiver, and microprocessor. Three finite impulse response (FIR) filters are used to decimate the sampling rate of the input seismic data according to user needs. A graphical user interface (GUI) has been designed for enabling the user to monitor the seismic waveform in real time, and process and adjust the parameters of the acquisition unit. The system casing is designed to resist harsh conditions of the environment. The prototype can represent the three component sensors data in the standard MiniSEED format. The digitizer stream seismic data from the remote station to the main center is based on TCP/IP connection. This protocol ensures data transmission without any losses as long as the data still exist in the ring buffer. The prototype was calibrated by real field testing. The prototype digitizer is integrated with the Egyptian National Seismic Network (ENSN), where a commercial instrument is already installed. Case studies shows that, for the same event, the prototype station improves the solution of the ENSN by giving accurate timing and seismic event parameters. Field test results shows that the event arrival time and the amplitude are approximately the same between the prototype digitizer and the calibrated digitizer. Furthermore, the frequency contents are similar between the two digitizers. Therefore, the prototype digitizer captures the main seismic parameters accurately, irrespective of noise existence.

8.
Molecules ; 29(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611755

RESUMO

Density functional theory (DFT) characterizations were employed to resolve the structural and energetic aspects and product selectivities along the mechanistic reaction paths of the nickel-catalyzed three-component unsymmetrical bis-allylation of alkynes with alkenes. Our putative mechanism initiated with the in situ generation of the active catalytic species [Ni(0)L2] (L = NHC) from its precursors [Ni(COD)2, NHC·HCl] to activate the alkyne and alkene substrates to form the final skipped trienes. This proceeds via the following five sequential steps: oxidative addition (OA), ß-F elimination, ring-opening complexation, C-B cleavage and reductive elimination (RE). Both the OA and RE steps (with respective free energy barriers of 24.2 and 24.8 kcal·mol-1) contribute to the observed reaction rates, with the former being the selectivity-controlling step of the entire chemical transformation. Electrophilic/nucleophilic properties of selected substrates were accurately predicted through dual descriptors (based on Hirshfeld charges), with the chemo- and regio-selectivities being reasonably predicted and explained. Further distortion/interaction and interaction region indicator (IRI) analyses for key stationary points along reaction profiles indicate that the participation of the third component olefin (allylboronate) and tBuOK additive played a crucial role in facilitating the reaction and regenerating the active catalyst, ensuring smooth formation of the skipped triene product under a favorably low dosage of the Ni(COD)2 catalyst (5 mol%).

9.
Molecules ; 29(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338344

RESUMO

The pyrrolidine nitroxides with four bulky alkyl substituents adjacent to the N-O∙ group demonstrate very high resistance to reduction with biogenic antioxidants and enzymatic systems. This makes them valuable molecular tools for studying the structure and functions of biomolecules directly in a living cell and for functional EPR and NMR tomography in vivo. The first example of highly strained pyrrolidine nitroxides with both ethyl and tert-butyl groups at each of the α-carbon atoms of the nitroxide moiety with cis-configuration of the tert-butyl groups was prepared using a three-component domino reaction of tert-leucine and 2,2-dimethylpentan-3-one with dimethyl fumarate with subsequent conversion of the resulting strained pyrrolidine into 1-pyrroline-1-oxide and addition of EtLi. The nitroxide has demonstrated unexpectedly fast reduction with ascorbate, the rate constant k2 = (2.0 ± 0.1) × 10-3 M-1s-1. This effect was explained by destabilization of the planar nitroxide moiety due to repulsion with the two neighboring tert-butyl groups cis to each other.

10.
Molecules ; 29(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39124868

RESUMO

As an important class of nitrogen-containing fused heterocyclic compounds, imidazo[1,2-a]pyridines often exhibit significant biological activities, such as analgesic, anticancer, antiosteoporosis, anxiolytic, etc. Using Y(OTf)3 as a Lewis acid catalyst, a simple and efficient method has been developed for the synthesis of C3-alkylated imidazo[1,2-a]pyridines through the three-component aza-Friedel-Crafts reaction of imidazo[1,2-a]pyridines, aldehydes, and amines in the normal air atmosphere without the protection of inert gas and special requirements for anhydrous and anaerobic conditions. A series of imidazo[1,2-a]pyridine derivatives were obtained with moderate to good yields, and their structures were confirmed by 1H NMR, 13C NMR, and HRMS. Furthermore, this conversion has the advantages of simple operation, excellent functional group tolerance, high atomic economy, broad substrate scope, and can achieve gram-level reactions. Notably, this methodology may be conveniently applied to the further design and rapid synthesis of potential biologically active imidazo[1,2-a]pyridines with multifunctional groups.

11.
Molecules ; 29(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675610

RESUMO

A chemselective catalyst-free three-component 1,3-dipolar cycloaddition has been described. The unique polycyclic THPI and THIQs were creatively employed as dipolarophiles, which led to the formation of functionalized ß-tetrahydrocarboline- and tetrahydroisoquinoline-fused spirooxindoles in 60-94% of yields with excellent diastereoselectivities (10: 1->99: 1 dr). This reaction not only realizes a concise THPI- or THIQs-based 1,3-dipolar cycloaddition, but also provides a practical strategy for the construction of two distinctive spirooxindole skeletons.

12.
Angew Chem Int Ed Engl ; 63(20): e202401750, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38407379

RESUMO

The catalytic performance for electrocatalytic CO2 reduction reaction (CO2RR) depends on the binding strength of the reactants and intermediates. Covalent organic frameworks (COFs) have been adopted to catalyze CO2RR, and their binding abilities are tuned via constructing donor-acceptor (DA) systems. However, most DA COFs have single donor and acceptor units, which caused wide-range but lacking accuracy in modulating the binding strength of intermediates. More elaborate regulation of the interactions with intermediates are necessary and challenge to construct high-efficiency catalysts. Herein, the three-component COF with D-A-A units was first constructed by introducing electron-rich diarylamine unit, electron-deficient benzothiazole and Co-porphyrin units. Compared with two-component COFs, the designed COF exhibit elevated electronic conductivity, enhanced reducibility, high efficiency charge transfer, further improving the electrocatalytic CO2RR performance with the faradic efficiency of 97.2 % at -0.8 V and high activity with the partial current density of 27.85 mA cm-2 at -1.0 V which exceed other two-component COFs. Theoretical calculations demonstrate that catalytic sites in three-component COF have suitable binding ability of the intermediates, which are benefit for formation of *COOH and desorption of *CO. This work offers valuable insights for the advancement of multi-component COFs, enabling modulated charge transfer to improve the CO2RR activity.

13.
Angew Chem Int Ed Engl ; : e202413949, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39148491

RESUMO

Herein, we report a synergistic photoredox/palladium catalytic system for the efficient enantioconvergent synthesis of axially chiral esters from racemic heterobiaryl (pseudo)halides (bromides/triflates) with CO2 and alkyl bromides under mild conditions. A wide range of axially chiral esters were obtained in good to high yields with excellent enantioselectivities. Detailed mechanistic studies unveiled that the ratio of photocatalyst and palladium catalyst exhibited significant impact on the chemo- and enantioselectivities of the reaction. Kinetic studies and control experiments supported the proposed mechanism involving cascade asymmetric carboxylation followed by SN2 substitution. The achievement of high enantioselectivity relies not only on the choice of synergistic metallaphotoredox catalysts but also on the utilization of alkyl bromides, which trap the generated chiral carboxylic anions in situ, thus preventing their immediate racemization.

14.
Angew Chem Int Ed Engl ; 63(13): e202314208, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38240738

RESUMO

In modern organic chemistry, harnessing the power of multicomponent radical reactions presents both significant challenges and extraordinary potential. This article delves into this scientific frontier by addressing the critical issue of controlling selectivity in such complex processes. We introduce a novel approach that revolves around the reversible addition of thiyl radicals to multiple bonds, reshaping the landscape of multicomponent radical reactions. The key to selectivity lies in the intricate interplay between reversibility and the energy landscapes governing C-C bond formation in thiol-yne-ene reactions. The developed approach not only allows to prioritize the thiol-yne-ene cascade, dominating over alternative reactions, but also extends the scope of coupling products obtained from alkenes and alkynes of various structures and electron density distributions, regardless of their relative polarity difference, opening doors to more versatile synthetic possibilities. In the present study, we provide a powerful tool for atom-economical C-S and C-C bond formation, paving the way for the efficient synthesis of complex molecules. Carrying out our experimental and computational studies, we elucidated the fundamental mechanisms underlying radical cascades, a knowledge that can be broadly applied in the field of organic chemistry.

15.
Beilstein J Org Chem ; 20: 661-671, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590540

RESUMO

Herein, we report a visible-light-mediated palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines, affording unsaturated γ- and ε-amino acid derivatives with diverse structures. In this methodology, the diazo compound readily transforms into a hybrid α-ester alkylpalladium radical with the release of dinitrogen. The radical intermediate selectively adds to the double bond of a 1,3-diene or allene, followed by the allylpalladium radical-polar crossover path and selective allylic substitution with the amine substrate, thereby leading to a single unsaturated γ- or ε-amino acid derivative. This approach proceeds under mild and simple reaction conditions and shows high functional group tolerance, especially in the incorporation of various bioactive molecules. The studies on scale-up reactions and diverse derivatizations highlight the practical utility of this multicomponent reaction protocol.

16.
Chemistry ; 29(70): e202303005, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37823842

RESUMO

Environmental issues are becoming more and more prominent, and bio-based polymers are essential to alleviate environmental degradation by replacing traditional polymers. With this context, a new family of functional isosorbide-based polyesters and polyamides with high glass transition temperature are prepared via Passerini-Three component polymerization (P-3CP). To optimize the P-3CP conditions, the influence of the polymerization solvent, temperature, feed ratio on the molar mass of final polymers are investigated. The higher molar mass (up to 10100 g/mol) and yield (>70 %) are achieved under very mild conditions (30 °C, standard atmosphere). Functional side groups, such as alkenyl, alkynyl and methyl ester, were introduced into polymer structure via P-3CP by using functional isocyanides. The obtained polyesters and polyamides are characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectroscopies, differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). All polymers are thermal stable and amorphous with variable glass transition temperatures (Tg ). The obtained polyester has Tg up to 87.5 °C, while the Tg of polyamides (ISPA-2) is detected to be 97.5 °C depending on the amide bonds in the polymer backbone and the benzene ring side groups. The cytotoxicity is investigated by the CCK-8 assay against mBMSC cells to confirm the biological safety. Overall, this novel strategy provides an efficient approach to produce functional isosorbide-based polyesters and polyamides, which are promising prospect for being applied to biodegradable materials.

17.
Chemistry ; 29(3): e202202820, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36239082

RESUMO

A three-component reaction of N, N-disubstituted aniline, α-diazo ester, and an allylic electrophile has been realized by [Rh(II)]2 /Xantphos catalysis, providing a direct access to various aniline derivatives bearing diaryl allylic quaternary centers in good yields. The synthetic utility of this protocol was demonstrated by facile derivatization of the products for preparation of biologically relevant molecules and structural scaffolds, which offers a high potential for increasing the molecular diversity. Mechanistic studies identified α, α-diarylacetate species as an active intermediate, thereby revealing the presence of a C(sp2 )-H functionalization of aniline derivatives/allylic alkylation cascade in this attractive catalytic transformation.


Assuntos
Compostos de Anilina , Estrutura Molecular , Estereoisomerismo , Alquilação , Catálise
18.
Chem Rec ; 23(12): e202300275, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37772656

RESUMO

Over the past decades, asymmetric photochemical synthesis has garnered significant attention for its sustainability and unique ability to generate enantio-enriched molecules through distinct reaction pathways. Photochemical asymmetric three-component reactions have demonstrated significant potential for the rapid construction of chiral compounds with molecular diversity and complexity. However, noteworthy challenges persist, including the participation of high-energy intermediates such as radical species, difficulties in precise control of stereoselectivity, and the presence of competing background and side reactions. Recent breakthroughs have led to the development of sophisticated strategies in this field. This review explores the intricate mechanisms, synthetic applications, and limitations of these methods. We anticipate that it will contribute towards advancing asymmetric catalysis, photochemical synthesis, and green chemistry.

19.
Chem Rec ; 23(11): e202300121, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37309268

RESUMO

Harnessing visible-light in organic synthesis is one of the most effective methods that aligns with green and sustainable chemistry principles and hence skyrocketed in the last two decades. Similarly, three-component 1,2-dicarbofunctionalization of alkenes and alkynes has recently been a great choice to construct complex molecular systems in an easy and rapid manner. Therefore, light-induced reactions can be an excellent alternative to carry out 1,2-dicarbofunctionalization reactions, and very recently, organic chemists across the globe have fascinated us with their interesting articles. In this present review, we have summarized the recent advancements in the area of visible light induced three-component 1,2-dicarbofunctionalization of alkenes and alkynes till March 2023. We have categorized the discussion based on the catalysts used to carry out the transformations for better understanding and different important aspects of these transformations have also been covered.

20.
Mol Divers ; 27(2): 837-843, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35668164

RESUMO

A Rh2(OAc)4 catalyzed three-component reaction of vinyl diazosuccinimides with alcohols and isatins has been reported, which provides a practical assess to the direct assembly of succinimide and isatin hybrid molecules in good-to-high yields with excellent stereoselectivity. The antiproliferation activity of these synthesized succinimide and isatin hybrid products has been tested via the CCK8 assay in different cancer cell lines, and compounds 4g (SJSA-1, IC50 = 3.82 µM) and 4r (HCT-116, IC50 = 9.02 µM) exhibit higher anticancer potency than other tested compounds.


Assuntos
Antineoplásicos , Isatina , Isatina/farmacologia , Estrutura Molecular , Antineoplásicos/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Succinimidas/farmacologia , Relação Estrutura-Atividade , Linhagem Celular Tumoral
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