- Pyrrolidine catalyzed novel domino reaction for the synthesis of polysubstituted 4-oxocyclohexanecarbaldehyde derivatives
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A novel domino reaction catalyzed by an organic molecule based on α,β-unsaturated aromatic aldehydes and methylethylketones has been developed. The progress allows one-pot and efficient synthesis of polysubstituted 4-oxocyclohexanecarbaldehyde derivatives via pyrrolidine mediated under mild conditions. The reaction consists of three consecutive reactions: an aldol condensation reaction and a tandem inter-Michael-intra- Michael addition reaction. Copyright
- Bao, Feng-Zu,Wang, Xiao-Bing,Kong, Ling-Yi
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- Synthesis and conformational studies of newly synthesized cis-2r,6c-distyryltetrahydro thiopyran-4-one and its oxime: Comparison of experimental and theoretical NMR spectral data
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The cis-2r,6c-distyryltetrahydro thiopyran-4-one (4) was synthesized by the reaction of dicinnamylacetone with hydrogen sulphide. cis-2r,6c- distyryltetrahydro thiopyran-4-one oxime (5) was synthesized via oximination of 4. The synthesized compounds were
- Vimalraj,Vijayalakshmi,Umayaparvathi
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- Palladium-Catalyzed Aminomethylation of Nitrodienes and Dienones via Double C—N Bond Activation
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A new strategy for the generation of the active Pd-alkyl species from aminal via C—N bond activation has been established, in which the formation of zwitterionic intermediate through aza-Michael addition of aminal to nitrodienes or dienones is identified as a key step for the activation of the C—N bond. The efficient strategy has enabled a new palladium-catalyzed α-aminomethylation of nitrodienes and dienones via double C—N bond activation. The scope and versatility of the reaction were demonstrated and a broad range of substrates bearing electron-donating and -withdrawing groups on the aromatic rings were all compatible with this reaction to furnish the desired α-aminomethylated products in moderate to good yields with excellent regioselectivities and E/Z selectivities.
- Yu, Bangkui,Gao, Bao,Zhang, Xuexia,Zhang, Haocheng,Huang, Hanmin
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supporting information
p. 566 - 570
(2021/02/01)
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- Intermolecular Multiple Dehydrogenative Cross-Couplings of Ketones with Boronic Acids and Amines via Copper Catalysis
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An efficient and versatile oxidative coupling reaction was developed for the synthesis of valuable β-functionalized unsaturated ketones and meta-substituted phenols. In the case of intramolecular reactions, achieving rapid molecular complexity through multiple dehydrogenative couplings is already a well-established strategy. Herein, we report an intermolecular multiple dehydrogenative coupling between ketones and nucleophilic amines or boronic acids using inexpensive copper(I) oxide as a catalyst. This method provides a facile access to highly desirable chemical products such as α,β-unsaturated ketones, enaminones, and synthetically relevant meta-substituted phenols. (Figure presented.).
- Wang, Tianzhang,Chen, Guowei,Lu, Yu-Jing,Chen, Qian,Huo, Yanping,Li, Xianwei
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supporting information
p. 3886 - 3892
(2019/07/19)
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- A Broad-Spectrum Synthesis of Tetravinylethylenes
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The first general synthesis of compounds of the tetravinylethylene (TVE) family is reported. Ramirez-type dibromo-olefination of readily accessible penta-1,4-dien-3-ones generates 3,3-dibromo[3]dendralenes, which undergo twofold Negishi, Suzuki–Miyaura or Mizoroki–Heck reactions with a wide variety of olefinic coupling partners. This route delivers a broad range of unsymmetrically substituted tetravinylethylenes with up to three different alkenyl substituents attached to the central C=C bond. The extensive scope of the approach is demonstrated by the preparation of the first higher order oligo-alkenic through-conjugated/cross-conjugated hybrid compounds. An unsymmetrically substituted TVE is shown to undergo a domino electrocyclization–cycloaddition with high site-selectivity and diastereoselectivity, thereby demonstrating the substantial synthetic potential of substituted TVEs for controlled, rapid structural complexity generation.
- Horvath, Kelsey L.,Newton, Christopher G.,Roper, Kimberley A.,Ward, Jas S.,Sherburn, Michael S.
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p. 4072 - 4076
(2019/03/22)
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- Antiparasitic activity of synthetic curcumin monocarbonyl analogues against Trichomonas vaginalis
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Trichomoniasis is a parasitic infection caused by Trichomonas vaginalis and it is considered to be the most common non-viral sexually transmitted infection in the world. Since the 1960s, nitroimidazoles such as metronidazole are the drugs of choice for the treatment of trichomoniasis, but many adverse effects and allergic reactions may result from their use. Reports of metronidazole-resistant infections also highlight the importance for the search of new anti-T. vaginalis agents. Considering this, herein we report the anti-T. vaginalis evaluation of 21 synthetic monocarbonyl analogues of curcumin, which itself has been reported to possess antiparasitic potential. From the in vitro analysis of the synthetic molecules, untreated trophozoites, and metronidazole at 100 μM, it was observed that three curcumin analogues (3a, 3e, and 5e) exhibited anti-T. vaginalis activity comparable to metronidazole (no significant statistical difference). Optimal antiparasitic concentrations were determined to be 80 μM and 90 μM for propanone derivatives 3a and 3e, respectively, and 200 μM for cyclohexanone derivative 5e. Kinetic growth curves showed that, after 24 h, the trophozoites were completely inhibited. At the tested concentrations, natural curcumin did not significantly inhibit the growth of trophozoites, therefore demonstrating that the designed synthetic molecules not only have better chemical stability, but also higher anti-T. vaginalis potential. Cytotoxicity analysis, performed on VERO cells, demonstrated low, moderate and high cytotoxic effects for analogues 3e, 5e and 3a, respectively. This study suggests that these analogues possess chemical features of interest to be further explored as alternatives for the treatment of trichomoniasis.
- Carapina da Silva, Caroline,Pacheco, Bruna Silveira,das Neves, Raquel Nascimento,Dié Alves, Mirna Samara,Sena-Lopes, ?ngela,Moura, Sidnei,Borsuk, Sibele,de Pereira, Claudio Martin Pereira
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p. 367 - 377
(2019/01/03)
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- Synthesis of Asymmetrical 2,6-Diarylpyridines from Linear α,β,γ,δ-Unsaturated Ketones by Addition of Ammonium Formate Followed by Annulation
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A simple and efficient method has been established for the synthesis of asymmetrical 2,6-diarylpyridines by cyclization of α,β,γ,δ-unsaturated ketones with ammonium formate under air atmosphere. The reaction is metal-free and operationally convenient from readily available starting materials. Thirty-three examples have been presented, most of which show good yields.
- Chen, Rener,Gao, Yejun,Ma, Yongmin
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p. 3875 - 3882
(2019/10/11)
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- Potent and Selective Inhibitors of Trypanosoma cruzi Triosephosphate Isomerase with Concomitant Inhibition of Cruzipain: Inhibition of Parasite Growth through Multitarget Activity
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Triosephosphate isomerase (TIM) is an essential Trypanosoma cruzi enzyme and one of the few validated drug targets for Chagas disease. The known inhibitors of this enzyme behave poorly or have low activity in the parasite. In this work, we used symmetrical diarylideneketones derived from structures with trypanosomicidal activity. We obtained an enzymatic inhibitor with an IC50value of 86 nm without inhibition effects on the mammalian enzyme. These molecules also affected cruzipain, another essential proteolytic enzyme of the parasite. This dual activity is important to avoid resistance problems. The compounds were studied in vitro against the epimastigote form of the parasite, and nonspecific toxicity to mammalian cells was also evaluated. As a proof of concept, three of the best derivatives were also assayed in vivo. Some of these derivatives showed higher in vitro trypanosomicidal activity than the reference drugs and were effective in protecting infected mice. In addition, these molecules could be obtained by a simple and economic green synthetic route, which is an important feature in the research and development of future drugs for neglected diseases.
- Aguilera, Elena,Varela, Javier,Birriel, Estefanía,Serna, Elva,Torres, Susana,Yaluff, Gloria,de Bilbao, Ninfa Vera,Aguirre-López, Beatriz,Cabrera, Nallely,Díaz Mazariegos, Selma,de Gómez-Puyou, Marieta Tuena,Gómez-Puyou, Armando,Pérez-Montfort, Ruy,Minini, Lucia,Merlino, Alicia,Cerecetto, Hugo,González, Mercedes,Alvarez, Guzmán
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supporting information
p. 1328 - 1338
(2016/07/20)
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- Chemoselective biohydrogenation of α,β- and α,β,γ,δ-unsaturated ketones by the marine-derived fungus Penicillium citrinum CBMAI 1186 in a biphasic system
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To broaden the range of applicability of a reduction reaction mediated by the marine fungal strain Penicillium citrinum CBMAI 1186 to organic chemical processes, the ability of whole mycelia to grow in biphasic mixtures with organic solvents was tested with acetone, ethyl acetate, n-butanol, dichloromethane, n-hexane and toluene. n-Hexane was the least toxic solvent according to the amount of mycelial mass grown in an artificial sea water medium mixed with each solvent. Therefore, whole hyphae of P. citrinum CBMAI 1186 were used as biocatalysts in the chemoselective biotransformation of the carbon-carbon double bond in α,β-, di-α,β-, and mono-α,β,γ,δ-unsaturated ketones (3a, 3c-f) in a biphasic system of phosphate buffer and n-hexane (9:1). Only the di-α,β,γ,δ-unsaturated ketone (3b) was not biocatalyzed under these conditions. In general, there were good conversions of saturated ketones by the enoate reductase enzymes of P. citrinum CBMAI 1186.
- Ferreira, Irlon M.,Meira, Eloá B.,Rosset, Isac G.,Porto, André L.M.
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- New spiro (thio) barbiturates based on cyclohexanone and bicyclo [3.1.1]heptan-6-one by nonconcerted [1+5] cyclo addition reaction and their conformational structures
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Crossed-aldol condensation reaction of aromatic aldehydes with ketones such as; acetone and cyclohexanone leads to the efficient formation of cross conjugated α,β-unsaturated ketones in excellent yield. The intermolecular and then intramolecular Michael addition reaction of α,β-unsaturated ketones derived from acetone and cyclohexanone with (thio)barbituric acids lead to synthesis new type of 7,11-diaryl-2,4-diazaspiro[5.5]undecane-1,3,5,9-tetraone and 2,4-diaryl-1'H-spiro[bicyclo[3.3.l]nonane-3,5'-pyrimidine]-2',4',6',9(3'H)-tetraone, respectively in good yield. Structure elucidation is carried out by 1H NMR, 13C NMR, FT-IR, UV-Visible, mass spectroscopy and X-ray crystallography techniques. A possible mechanism of the formation is discussed. The structural conformation also demonstrated by coupling constants derived from dihedral angles between vicinal and geminal protons. The 1H NMR spectra of NH protons of spiro compounds derived from barbituric acid show a broad singlet peak instead, these protons in the spiro compounds derived from thiobarbituric acid show two distinct peaks.
- Pesyan, Nader Noroozi,Noori, Sirons,Poorhassan, Soodabeh,ahin, Ertan
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p. 423 - 440
(2015/02/02)
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- Sulfamic acid: An efficient, cost-effective and green catalyst for crossed-aldol condensation of ketones with aromatic aldehydes under solvent-free
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Aromatic aldehydes undergo crossed-aldol condensation with ketones in the presence of catalytic amount of sulfamic acid (SA) to afford the corresponding α, β-unsaturated aldol products under solvent-free conditions in good to high yields at 45-80 °C.
- Rostami, Amin,Ahmad-Jangi, Firoz
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experimental part
p. 1029 - 1032
(2012/06/01)
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- 1,5-bis (2-hydroxyphenyl)pent-1,4-diene-3-one: A lead compound for the development of broad-spectrum antibacterial agents
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A systematic and comparative study has been made starting from a naturally-occurring chalcone nucleus to design effective antibacterial agents. The present investigation established 1,5-bis(2-hydroxyphenyl)pent-1,4-diene-3- one (1c) as a lead compound with potential against a panel of pathogenic bacterial strains. Staphylococcus (coagulase negative), Escherichia coli, Pseudomonas aeruginosa, Acenetobacter sp. and Klebsiella pneumoniae. Gentamycine and tetracycline were used as reference drugs. The mode of antibacterial action of Ic was also studied by scanning electron microscopy, which showed membrane disruption and cell lysis of the organisms during the exposure of the tested compound. In vitro toxicity tests demonstrated that all the bioactive compounds showed far less toxicity against human erythrocytes.
- Rani,Jain, Sapna,Kumar, Rita,Kumar, Anil
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experimental part
p. 31 - 35
(2011/07/31)
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- Examination of growth inhibitory properties of synthetic chalcones for which antibacterial activity was predicted
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A large series of chalcones were synthesized and studied against Staphylococcus aureus and Escherichia coli. Chalcones were either unsubstituted in ring A or possessed 4′-chloro or 3′,4′,5′-trimethoxy groups. Their other ring B was variously substituted. It was found that the anti-staphylococcal activity of chalcones was related to the energy difference between the two highest occupied molecular orbitals (HOMO and HOMO-1). Presence of hydroxyl group in ring B was not a determinant factor for the anti-staphylococcal activity, but the lipophilicity of ring A of the hydroxyl chalcones was of importance.
- Batovska, Daniela,Parushev, Stoyan,Stamboliyska, Bistra,Tsvetkova, Iva,Ninova, Mariana,Najdenski, Hristo
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experimental part
p. 2211 - 2218
(2009/09/30)
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- Synthesis and anti-bacterial properties of mono-carbonyl analogues of curcumin
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The synthesis of three series of curcumin analogues with mono-carbonyl is described. Their in vitro antibacterial activities against seven Gram-positive and Gram-negative bacteria were tested and the effect of substituents on the aryl ring and the space structure of the linking strain were discussed. It was observed that part of the derivatives displayed significant activity when compared with curcumin and most of them exhibited activity against the ampicillin-resisted Enterobacter cloacae. Compounds A12, B09, B13, B14 and C09 show remarkable antibacterial activity in vitro. The result showed that heterocycle or long-chain substituents may enhance the activity of curcumin analogues.
- Liang, Guang,Yang, Shulin,Jiang, Lijuan,Zhao, Yu,Shao, Lili,Xiao, Jian,Ye, Faqing,Li, Yueru,Li, Xiaokun
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p. 162 - 167
(2008/09/19)
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- Synthesis and anti-inflammatory activities of mono-carbonyl analogues of curcumin
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Curcumin has been extensively studied for its anti-inflammatory activities. However, its potential beneficial effects on various disease preventions and treatments are limited by its unstable structure. The β-diketone moiety renders curcumin to be rapidly metabolized by aldo-keto reductase in liver. In the present study, a series of curcumin analogues with more stable chemical structures were synthesized and several compounds showed an enhanced ability to inhibit lipopolysaccharide (LPS)-induced TNF-α and IL-6 synthesis in macrophages.
- Liang, Guang,Li, Xiaokun,Chen, Li,Yang, Shulin,Wu, Xudong,Studer, Elaine,Gurley, Emily,Hylemon, Phillip B.,Ye, Faqing,Li, Yueru,Zhou, Huiping
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p. 1525 - 1529
(2008/09/19)
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- Study on the substituents' effects of a series of synthetic chalcones against the yeast Candida albicans
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A large series of chalcones were synthesized and studied for activity against Candida albicans. The SAR analysis showed that the antifungal activity was highly dependent on the substitution pattern of the aryl rings and correlated to a large extent with the ability of compounds to interact with sulfhydryl groups. The most active were the hydroxylated chalcones as their activity related to the location of the phenolic group in the aryl ring B as follows: o-OH > p-OH ~ 3,4-di-OH > m-OH. These and other correlations obtained strongly contribute to the knowledge for design of anticandidal chalcones.
- Batovska,Parushev,Slavova,Bankova,Tsvetkova,Ninova,Najdenski
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- Amine-catalyzed aldol condensation in the presence of lithium perchlorate
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A catalytic aldol condensation in the presence of lithium perchlorate and tertiary amines is described giving pure products in high yields. The aldol condensation can be performed even in the presence of hydrated lithium perchlorate. Georg Thieme Verlag Stuttgart.
- Arnold, Aline,Markert, Morris,Mahrwald, Rainer
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p. 1099 - 1102
(2007/10/03)
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- Synthesis of α, α′-bis(substituted benzylidene)ketones catalysed by a SOCl2/EtOH reagent
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The cross-aldol condensations of cyclopentanone, cyclohexanone and acetone with benzaldehyde or cinnamaldehyde were catalysed in the presence of SOCl 2, in anhydrous ethanol to synthesise α, α′ -bis(substituted benzylidene) ketones with excellent yields(92-97%).
- Hu, Zhi Guo,Liu, Jun,Zeng, Ping Li,Dong, Zhi Bing
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- Non-subliming Mid-UV dyes and ultra-thin organic arcs having differential solubility
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Mid-UV dyes enabling ultra thin antireflection coatings for multi-layer i-line photoetching are produced from bichalcones; bis-a-cyanoacrylates/bis-cyanoacrylamides; and 1.4 divinylbenzenes. The dyes are nonsubliminal and differentially insoluble in standard photoresist solvents.
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- Equilibrium acidities of some α,ω-diphenylpolyenes
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Cesium ion pair acidities were measured in THF for a series of diphenylmethane vinylogues that form α,ω-diphenylpolyenyl anions with linearly conjugated chains of 3-9 carbon atoms. The dissociation constants of the diphenylpolyenyls in THF were determined by UV-vis spectroscopy and are rationalized with an electrostatic model. Acidity and dissociation data were combined with measurements of stereoisomer equilibria to estimate the differences in delocalization energy among the diphenylpolyenyl ions. The experimental differences in acidity correlate well with AMI and molecular mechanics (MMPI) calculations.
- Thiele, Georg,Streitwieser, Andrew
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p. 446 - 454
(2007/10/02)
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