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1.
ACS Macro Lett ; 11(5): 630-635, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35570817

RESUMO

Ruthenium alkoxymethylidene complexes have recently come into view as competent species for metathesis copolymerization reactions when coupled with appropriate comonomer targets. Here, we explore the ability of Fischer-type carbenes to participate in cascade alternating metathesis cyclopolymerization (CAMC) through facile terminal alkyne addition. The combination of diyne monomers and an equal feed ratio of low-strain dihydrofuran leads to a controlled chain-growth copolymerization with high degrees of alternation (>97% alternating diads) and produces degradable polymer materials with low dispersities and targetable molecular weights. When combined with enyne monomers, this method is amenable to the synthesis of alternating diblock copolymers that can be fully degraded to short oligomer fragments under aqueous acidic conditions. This work furthers the potential for the generation of functional metathesis materials via Fischer-type ruthenium alkylidenes.


Assuntos
Rutênio , Alcinos , Di-Inos , Polimerização , Polímeros
2.
Molecules ; 27(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630673

RESUMO

Cu-catalyzed 1,3-dipolar cycloaddition of ethyl 2-azidoacetate to iodobuta-1,3-diynes and subsequent Sonogashira cross-coupling were used to synthesize a large series of new triazole-based push-pull chromophores: 4,5-bis(arylethynyl)-1H-1,2,3-triazoles. The study of their optical properties revealed that all molecules have fluorescence properties, the Stokes shift values of which exceed 150 nm. The fluorescent properties of triazoles are easily adjustable depending on the nature of the substituents attached to aryl rings of the arylethynyl moieties at the C4 and C5 atoms of the triazole core. The possibility of 4,5-bis(arylethynyl)-1,2,3-triazoles' application for labeling was demonstrated using proteins and the HEK293 cell line. The results of an MTT test on two distinct cell lines, HEK293 and HeLa, revealed the low cytotoxicity of 4,5-bis(arylethynyl)triazoles, which makes them promising fluorescent tags for labeling and tracking biomolecules.


Assuntos
Di-Inos , Triazóis , Reação de Cicloadição , Células HEK293 , Células HeLa , Humanos , Triazóis/farmacologia
3.
J Am Chem Soc ; 144(17): 7750-7757, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442671

RESUMO

The hexadehydro-Diels-Alder (HDDA) reaction converts a 1,3-diyne bearing a tethered alkyne (the diynophile) into bicyclic benzyne intermediates upon thermal activation. With only a few exceptions, this unimolecular cycloisomerization requires, depending on the nature of the atoms connecting the diyne and diynophile, reaction temperatures of ca. 80-130 °C to achieve a convenient half-life (e.g., 1-10 h) for the reaction. In this report, we divulge a new variant of the HDDA process in which the tether contains a central, quaternized nitrogen atom. This construct significantly lowers the activation barrier for the HDDA cycloisomerization to the benzyne. Moreover, many of the ammonium ion-based, alkyne-containing substrates can be spontaneously assembled, cyclized to benzyne, and trapped in a single-vessel, ambient-temperature operation. DFT calculations provide insights into the origin of the enhanced rate of benzyne formation.


Assuntos
Alcinos , Compostos de Amônio , Alcinos/química , Reação de Cicloadição , Di-Inos , Temperatura
4.
J Org Chem ; 87(9): 5577-5591, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35389223

RESUMO

An efficacious synthetic solution to offer functionalized bisindoles and indoles has been developed based on catalyst-controlled C-H functionalization of pyrazolidinones and 1,3-diynes with highly selective control of both chemoselectivity and regioselectivity. This straightforward pathway conquers chemo- and regioselectivity challenges concerning the use of 1,3-diynes.


Assuntos
Di-Inos , Indóis , Catálise
5.
Org Biomol Chem ; 20(18): 3755-3762, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35420116

RESUMO

A highly regio- and chemoselective synthesis of 1H-isoindoliums through a facile and novel cascade cyclization reaction of propargylamine-based 1,6-diynes under mild conditions has been developed. Different functional groups were compatible under the optimized reaction conditions, giving the corresponding products in up to 94% yields. Upon treatment with a base, the alkyne moiety of 1H-isoindoliums could be further transformed to allenes in excellent yields.


Assuntos
Di-Inos , Halogenação , Catálise , Ciclização , Estrutura Molecular , Pargilina/análogos & derivados , Propilaminas
6.
Org Lett ; 24(15): 2899-2904, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35404065

RESUMO

An efficient synthetic organic transformation was developed to access isoquinoline-substituted isobenzofurans by reaction of substituted 1,5-diynes with isoquinoline N-oxides. Moderate to excellent yields of isoquinoline-derived isobenzofurans were achieved by formation of a new C-C and two C-O bonds in the presence of copper catalyst in one pot. whereas quinoline-substituted isobenzofurans were obtained when the reaction was conducted using quinoline N-oxides and 1,5-diynes in the presence copper catalyst.


Assuntos
Cobre , Di-Inos , Catálise , Cobre/química , Di-Inos/química , Isoquinolinas , Óxidos/química , Quinolinas
7.
Chem Asian J ; 17(8): e202101408, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35243791

RESUMO

An efficient intramolecular cyclization reaction was developed to achieve indenone derivatives. The substituted 1,5-diyenes were converted to the corresponding indenones via a gold-catalyzed organic transformation, and moderate to excellent yields of the title molecules were obtained via formation of two C=O and one C-C bonds under mild reaction conditions in one pot.


Assuntos
Di-Inos , Ouro , Catálise , Cátions , Ciclização , Di-Inos/química , Ouro/química , Estrutura Molecular
8.
J Org Chem ; 87(6): 4134-4153, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35245072

RESUMO

Air-stable, highly abundant, and cost-effective Co(III)-catalyzed redox-neutral [4 + 2]-annulation of aromatic sulfoxonium ylides with 1,3-diynes providing useful substituted 1-naphthol derivatives in a regioselective manner is described. Further, the prepared 1-naphthols having internal alkyne were converted into useful polycarbocyclic molecules and spiro-dienone derivatives in good-to-excellent yields. A possible reaction mechanism involving ortho C-H activation as a key step was proposed and supported by deuterium labeling and kinetic isotope labeling studies.


Assuntos
Cobalto , Di-Inos , Alcinos , Catálise , Naftóis
9.
Chem Soc Rev ; 51(3): 869-994, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35005762

RESUMO

This review highlights the hydroelementation reactions of conjugated and separated diynes, which depending on the process conditions, catalytic system, as well as the type of reagents, leads to the formation of various products: enynes, dienes, allenes, polymers, or cyclic compounds. The presence of two triple bonds in the diyne structure makes these compounds important reagents but selective product formation is often difficult owing to problems associated with maintaining appropriate reaction regio- and stereoselectivity. Herein we review this topic to gain knowledge on the reactivity of diynes and to systematise the range of information relating to their use in hydroelementation reactions. The review is divided according to the addition of the E-H (E = Mg, B, Al, Si, Ge, Sn, N, P, O, S, Se, Te) bond to the triple bond(s) in the diyne, as well as to the type of the reagent used, and the product formed. Not only are the hydroelementation reactions comprehensively discussed, but the synthetic potential of the obtained products is also presented. The majority of published research is included within this review, illustrating the potential as well as limitations of these processes, with the intent to showcase the power of these transformations and the obtained products in synthesis and materials chemistry.


Assuntos
Di-Inos , Catálise
10.
Cell Biochem Biophys ; 80(1): 229-243, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34709575

RESUMO

Acne is one of the most common dermatological skin problem caused due to inflammation of the skin, leading to unfavorable growth of Propionibacterium acnes. It is a slow growing anaerobic, gram-positive bacterium that releases chemotactic factors and leads to the complex pathogenicity of acne. There are several acne treatments/therapies available, but topical therapy is usually the first choice for mild to moderate acne, and as the severity of the acne increases, the treatment modalities fail. There are many acne treatment options available, but topical therapy is best suited for mild - to - moderate skin problems, and then as the seriousness of the acne grows, the therapeutic approaches fall short. Biosurfactants are surfactants produced from plants or animals; Saponins are plant derived non-ionic biosurfactants which have steroidal and triterpenic glycosides distributed largely in plant kingdom. Numerous studies conducted by scientists have established the antimicrobial activity of and are considered more advantageous over synthetic precursors as they are eco-friendly, cheap and non-toxic. The present study was undertaken to investigate the antibacterial activity of saponins (bio-surfactants) characterized using mass spectroscopy against acne-causing bacteria. The discharge of cellular components including protein and UV-sensitive materials in the cell-free supernatant was provoked by saponin, confirming the cellular and membrane disturbances.. Furthermore, various morphological changes on the bacterial cell surface structure by Transmission electron microscopy and scanning electron microscopy revealed the disruption of the cell integrity leading to death. Results confirmed presence of non-ionic surfactants primarily affecting the disruption and destruction to the bacteria which indicates that saponins are efficient components with great potential applications in various pharmaceutical preparations. Effects of Prednisolone derivative and Panaxydol: Biosurfactants on cell wall integrity of Acne-Causing Resistant Bacteria.


Assuntos
Acne Vulgar , Prednisolona , Acne Vulgar/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Parede Celular , Di-Inos , Álcoois Graxos , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Propionibacterium acnes
11.
Chem Commun (Camb) ; 58(27): 4376-4379, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35297437

RESUMO

A novel metal-free nitrative bicyclization of 1,7-diynes with tBuONO in the presence of H2O is reported, producing three types of skeletally diverse tricyclic pyrroles, namely pyrrolo[3,4-c]quinolines, chromeno[3,4-c]pyrroles and benzo[e]isoindoles, with moderate to good yields by simply tuning the linkers of the 1,7-diynes. This domino protocol demonstrates remarkable compatibility regarding 1,7-diynes with different linkers, such as nitrogen and oxygen atoms and a hydroxymethyl group, and tBuONO plays dual roles as a nitro precursor as well as a nitrogen atom source.


Assuntos
Di-Inos , Quinolinas , Catálise , Pirróis
12.
Am J Chin Med ; 50(1): 295-311, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34931585

RESUMO

Human oral squamous cell carcinomas (OSCCs) have high cancer mortality and a 5-year survival rate lower than that of most other carcinomas. New therapeutic strategies are required for the treatment and prevention against OSCCs. An approach to cancer therapy using plant-derived natural compounds has been actively in progress as a trend. Falcarindiol (FALC), or its isolated form Ostericum koreanum Kitagawa (O. koreanum), is present in many food and dietary plants, especially in carrots, and this compound has a variety of beneficial effects. However, biological activity of FALC has not been reported in OSCCs yet. This study aimed to demonstrate the antitumor effects of FALC against OSCCs, YD-10B cells. In this study, FALC was selected as a result of screening for compounds isolated from various natural products in YD-10B cells. FALC suppressed cell growth, and FALC-induced apoptotic cell death was mainly accompanied by the dephosphorylation of PI3K, AKT, mTOR, and p70S6K. The apoptotic cell death was also associated with autophagy as evidenced by the expression of Beclin-1, the conversion of LC3-II, and the formation of autophagosome. FALC-induced autophagy was accompanied by MAPKs including ERK1/2 and p38. Furthermore, FALC caused the antimetastatic effects by inhibiting the migration and invasion of YD-10B cells. Taken together, the findings suggest the potential value of FALC as a novel candidate for therapeutic strategy against OSCCs.


Assuntos
Morte Celular Autofágica , Neoplasias Bucais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Di-Inos , Álcoois Graxos , Humanos , Neoplasias Bucais/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa , Serina-Treonina Quinases TOR/metabolismo
13.
Int Immunopharmacol ; 101(Pt A): 108321, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34741869

RESUMO

BACKGROUND AND PURPOSE: Panaxynol (PAL, PubChem CID: 5281149) is a common natural minor component in Umbelliferae plants, such as Radix Saposhnikoviae Divaricatae. Modern pharmacology studies show that PAL has nutritional value and anti-inflammatory and other pharmaceutical activities. Therefore, the scientific hypothesis of PAL in the treatment of rheumatoid arthritis was put forward, and the hypothesis was further verified by Fibroblast-like synovial cells (RA-FLS) and Collagen Induced Arthritis (CIA) rats models. EXPERIMENTAL METHOD: CIA method was used to establish a rat arthritis model. After extracting RA-FLS, flow cytometry and immunofluorescence were used to explore the effect of PAL on the apoptosis and proliferation of RA-FLS. Wound healing and transwell experiment explored the effect of PAL on the migration and invasion of RA-FLS. Western blot analysis explored the inner mechanism of the effect of PAL on RA-FLS. At the same time, it also explored the role of PAL in CIA rats, including pathological section detection and western blot analysis. MAIN RESULTS: PAL can promote the apoptosis and inhibit the proliferation, migration and invasion of RA-FLS. PAL can also reduce joint swelling in CIA rats, reduce pannus formation and inflammatory infiltration in the joints. Western blot analysis showed that PAL mainly played a role through the TLR4/NF-κB signaling pathway. CONCLUSION: The results of in vivo and in vitro experiments show that PAL can effectively alleviate the condition of RA, and may be a potential drug for the treatment of RA.


Assuntos
Antirreumáticos/uso terapêutico , Apoptose/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Di-Inos/uso terapêutico , Álcoois Graxos/uso terapêutico , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/citologia , Receptor 4 Toll-Like/metabolismo , Animais , Western Blotting , Movimento Celular/efeitos dos fármacos , Feminino , Ratos , Ratos Wistar , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/metabolismo
14.
Molecules ; 26(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34641440

RESUMO

Quorum sensing (QS) is employed by the opportunistic pathogen Pseudomonas aeruginosa to regulate physiological behaviors and virulence. QS inhibitors (QSIs) are potential anti-virulence agents for the therapy of P. aeruginosa infection. During the screening for QSIs from Chinese herbal medicines, falcarindiol (the major constituent of Notopterygium incisum) exhibited QS inhibitory activity. The subinhibitory concentration of falcarindiol exerted significant inhibitory effects on the formation of biofilm and the production of virulence factors such as elastase, pyocyanin, and rhamnolipid. The mRNA expression of QS-related genes (lasB, phzH, rhlA, lasI, rhlI, pqsA, and rhlR) was downregulated by falcarindiol while that of lasR was not affected by falcarindiol. The transcriptional activation of the lasI promoter was inhibited by falcarindiol in the P. aeruginosa QSIS-lasI selector. Further experiments confirmed that falcarindiol inhibited the las system using the reporter strain Escherichia coli MG4/pKDT17. Electrophoretic mobility shift assay (EMSA) showed that falcarindiol inhibited the binding of the transcription factor LasR and the lasI promoter region. Molecular docking showed that falcarindiol interacted with the Tyr47 residue, leading to LasR instability. The decrease of LasR-mediated transcriptional activation was responsible for the reduction of downstream gene expression, which further inhibited virulence production. The inhibition mechanism of falcarindiol to LasR provides a theoretical basis for its medicinal application.


Assuntos
Apiaceae/química , Di-Inos/farmacologia , Álcoois Graxos/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum , Di-Inos/isolamento & purificação , Álcoois Graxos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação
15.
Immunopharmacol Immunotoxicol ; 43(6): 778-789, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34618611

RESUMO

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is an extreme form of non-alcoholic fatty liver disease. The present study concentrated on the role of Capillin, a polyacetylene compound isolated from Artemisia capillaris Thunb., in NASH development. MATERIALS AND METHODS: Palmitic acid (PA) was treated with FL83B hepatocytes, and high-fat diet was given to mouse to construct the NASH model in vivo. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, flow cytometry, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were carried out to measure the viability and apoptosis of FL83B hepatocytes. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to measure the mRNA expressions of infiltration markers (Cd11c, Ccr2, and Ly6c), fibrosis genes (Tgfß1, Col1a1, and Timp1), and alpha-smooth muscle actin (α-SMA). Western blot, immunofluorescence, and Enzyme-linked immunosorbent assay (ELISA) were implemented to examine the proteins of Caspase-3, Bcl2, Nrf2, HO-1, NLRP3, ASC, and Caspase-1, the ROS level, and oxidative stress markers (MDA, GSH-ST, SOD, and GSH-Px), and the lipid peroxidation level, respectively. Moreover, HE staining was manipulated to observe the histopathological changes in liver tissue. RESULTS: Capillin hampered PA-mediated hepatocytes apoptosis and enhanced cell viability. Furthermore, Capillin suppressed PA-mediated oxidative stress in hepatocytes, promoted Nrf2/HO-1 expression, and repressed NLRP3-ASC-Caspase1 inflammasome. The in vivo studies indicated that Capillin vigorously improves liver fat accumulation, oxidative stress, and liver injury in NASH mice. Mechanistically, Capillin repressed NLRP3-ASC-Caspase1 inflammasome and up-regulated the Nrf2-HO-1 pathway in the liver. CONCLUSION: Capillin ameliorates hepatocyte injury by dampening oxidative stress and repressing NLRP3 inflammasome in NASH mice.


Assuntos
Di-Inos/uso terapêutico , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Di-Inos/farmacologia , Relação Dose-Resposta a Droga , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo/fisiologia , Extratos Vegetais/farmacologia
16.
ChemMedChem ; 16(23): 3569-3575, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34414677

RESUMO

Forty samples of optically active falcarindiol analogues are synthesized by using the easily available C2 symmetric (R)- and (S)-1,1'-binaphth-2-ol (BINOL) in combination with Ti(Oi Pr)4 , Zn powder and EtI. Their anticancer activities on Hccc-9810, HepG2, MDA-MB-231, Hela, MG-63 and H460 cells are assayed to elucidate their structure-activity relationships. These results showed that the falcarindiol analogue (3R,8S)-2 i with the terminal double bond has the most potent anti-proliferation effect on Hccc-9810 cells with IC50 value of 0.46 µM. The falcarindiol analogue (3R,8S)-2 i can induce obvious Hccc-9810 cell apoptosis in a concentration-dependent manner by Hoechst staining and flow cytometry analysis. The proposed mechanism suggests that the falcarindiol analogue (3R,8S)-2 i increases LDH release and MDA content, and reduces the levels of SOD activity, which lead to the accumulation of oxidative stress and induce apoptosis in Hccc-9810 cells.


Assuntos
Antineoplásicos/farmacologia , Di-Inos/farmacologia , Álcoois Graxos/farmacologia , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Di-Inos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Álcoois Graxos/síntese química , Humanos , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade , Superóxido Dismutase/metabolismo
17.
J Nat Prod ; 84(8): 2138-2148, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34319736

RESUMO

A series of enantiomers of falcarinol analogues (2) were synthesized using a chiral 1,1'-binaphth-2-ol (BINOL)-based catalytic system. The neuroprotective effects of falcarinol (1a) and its analogues (2) on PC12 cells injured by sodium azide (NaN3) were investigated. The structure-function relationships and possible mechanism were studied. Pretreatment of PC12 cells with falcarinol analogues (R)-2d and (R)-2i for 1 h following addition of NaN3 and culture in a CO2 incubator for 24 h resulted in significant elevation of cell viability, as determined by a CCK-8 assay and Hoechst staining, with reduction of LDH release and MDA content, increase of SOD activity, and decrease of ROS stress, when compared with the activity of natural falcarinol (1a). These observations indicated that the falcarinol analogues (R)-2d and (R)-2i can protect PC12 cells against NaN3-induced apoptosis via increasing resistance to oxidative stress. For the first time, falcarinol (1a) and its analogue (R)-2i were found to have potential L-type calcium channel-blocking activity, as recorded using a manual patch clamp technique on HEK-293 cells stably expressing hCav1.2 (α1C/ß2a/α2δ1). These findings suggest that the mechanism of the L-type calcium channel-blocking activity of falcarinol (1a) and its analogue (R)-2i might be involved in neuroprotection by falcarinol-type analogues by inhibiting calcium overload in the upstream of the signaling pathway.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Di-Inos/farmacologia , Álcoois Graxos/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Bloqueadores dos Canais de Cálcio/síntese química , Sobrevivência Celular/efeitos dos fármacos , Di-Inos/síntese química , Álcoois Graxos/síntese química , Células HEK293 , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
18.
Org Lett ; 23(14): 5448-5451, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34180676

RESUMO

We report here a three-component, Cu(I)-catalyzed hexadehydro-Diels-Alder (HDDA) benzyne 1,2-difunctionalization reaction. This protocol allowed the introduction of two different carbon-based substituents onto the in situ-generated benzyne. These substituents were terminal monoynes or diynes partnered with propargylic, benzylic, or allylic chlorides. An example of a sequential HDDA reaction is demonstrated using the product of a 1,3-diyne and a propargylic halide, itself a newly created HDDA precursor.


Assuntos
Derivados de Benzeno/química , Di-Inos/química , Pargilina/química , Catálise , Cobre/química , Reação de Cicloadição , Estrutura Molecular , Pargilina/análogos & derivados
19.
Macromol Rapid Commun ; 42(16): e2100283, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34142404

RESUMO

Polyaddition via the Co-catalyzed hydroarylation of 1-(2-pyrimidinyl)pyrrole with aromatic diynes affords poly(arylenevinylene)s under mild conditions. This reaction avoids production of stoichiometric amounts of by-products. Although structural analysis of the obtained polymers reveals the presence of 1,1-vinylidene unit, switching the counter anion of the Co catalyst and steric hindrance of the diyne monomers improves the regioselectivity of the polymers. When a catalyst with bulky counter anions is used for the reaction of less hindered diyne monomers, 1,2-vinylene linkages are formed dominantly over 1,1-vinylidene linkages (93:7). The effect of the regioselectivity of the polymer on the optical and semiconducting properties is also evaluated.


Assuntos
Alcinos , Pirróis , Catálise , Di-Inos
20.
J Org Chem ; 86(14): 9428-9443, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34170693

RESUMO

The ruthenium(II)-catalyzed regioselective annulation of N-(7-azaindole)amides with 1,3-diynes has been demonstrated. Bioactive N-amino-7-azaindole has been used as a new bidentate directing group to furnish an array of 3-alkynylated isoquinolones. Furthermore, the developed protocol works efficiently for both aryl- and heteroaryl-substituted amides producing a range of pharmacologically useful 7-azaindole-based isoquinolones with a wide range of functionality.


Assuntos
Rutênio , Amidas , Catálise , Di-Inos , Indóis
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