93628-96-7Relevant academic research and scientific papers
Ag2CO3-catalyzed efficient synthesis of internal or terminal propargylicamines and chalcones via A3-coupling under solvent-free condition
Li, Ningbo,Xu, Shitang,Wang, Xueyan,Xu, Li,Qiao, Jie,Liang, Zhiwu,Xu, Xinhua
, p. 3993 - 3997 (2021/05/31)
Several simple, fast and practical protocols have been developed to synthesize internal or terminal propargylamines and chalcones via A3-coupling reaction of aldehydes, amines, and alkynes catalyzed by an easily available catalyst Ag2CO3 under solvent-free condition. The reaction proceeded smoothly to deliver various products in good-to-excellent yields with good functional group tolerance. Gram-scale preparation, bioactive molecule synthesis and asymmetric substrates have been demonstrated. Furthermore, plausible mechanisms for the synthesis of different products have been proposed.
Green method for high-selectivity synthesis of chalcone compounds
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Paragraph 0083-0086, (2021/10/02)
Under the condition of air, the water-soluble inorganic weak base is used as a catalyst to catalyze the hydrogen transfer reaction of the propargyl alcohol compound, so that the green synthesis of the high-trans selective chalcone compound is realized. Reaction temperature: 80 - 120 °C and reaction time 12 - 48 hours. To the technical scheme, any transition metal catalyst and ligand do not need to be used, inert gas protection is not needed, no other byproducts are generated, the atom economy 100%, green and environment friendliness are avoided, and the product is a high-selectivity (E)-type product. The reaction conditions are relatively low in requirement. Compared with the prior art, the alkali catalyst is obvious in advantages, and has a certain application prospect in the fields of organic synthesis, biochemistry, medicine and the like.
Transition-Metal-Free Catalytic Formal Hydroacylation of Terminal Alkynes
Yatabe, Takafumi,Mizuno, Noritaka,Yamaguchi, Kazuya
, p. 11564 - 11569 (2018/11/23)
Although hydroacylation is a very useful reaction for producing ketones from aldehydes with 100% atom efficiency, classical Rh-catalyzed hydroacylation presents several problems, including the need for transition metal catalysts, unwanted decarbonylation of aldehydes, and difficulty in regioselectivity control. However, formal hydroacylation utilizing the nucleophilicity of terminal alkynes can avoid these problems. In this work, we have achieved transition-metal-free formal hydroacylation of terminal alkynes using an Mg3Al-CO3-layered double hydroxide as a heterogeneous catalyst. This system was applicable to the efficient synthesis of α,β-unsaturated ketones with various substituents, and the catalyst can be reused without a significant loss of catalytic performance.
Synthetic and mechanistic studies on the solvent-dependent copper-catalyzed formation of indolizines and chalcones
Albaladejo, María José,Alonso, Francisco,González-Soria, María José
, p. 3446 - 3456 (2015/06/16)
Copper nanoparticles supported on activated carbon have been found to catalyze the multicomponent synthesis of indolizines from pyridine-2-carbaldehyde derivatives, secondary amines, and terminal alkynes in dichloromethane; in the absence of solvent, howe
Palladium-catalyzed and copper-mediated cross-coupling reaction of aryl- or alkenylboronic acids with acid chlorides under neutral conditions: Efficient synthetic methods for diaryl ketones and chalcones at room temperature
Ogawa, Daisuke,Hyodo, Keita,Suetsugu, Masato,Li, Jing,Inoue, Yoshiaki,Fujisawa, Mamoru,Iwasaki, Masayuki,Takagi, Kentaro,Nishihara, Yasushi
, p. 2565 - 2571 (2013/03/28)
Palladium-catalyzed cross-coupling reaction of aryl- or alkenylboronic acids with acid chlorides in the presence of copper(I) thiophene-2-carboxylate (CuTC) as an activator in diethyl ether at room temperature under strictly non-basic conditions affords the diaryl ketones or chalcones in moderate to excellent yields. A wide range of substrates bearing an electron-donating or an electron-withdrawing substituent on the aromatic ring are compatible.
Differential tuning of the electron transfer parameters in 1,3,5-triarylpyrazolines: A rational design approach for optimizing the contrast ratio of fluorescent probes
Cody, John,Mandal, Subrata,Yang, Liuchun,Fahrni, Christoph J.
supporting information; experimental part, p. 13023 - 13032 (2009/03/12)
A large class of cation-responsive fluorescent sensors utilizes a donor-spacer-acceptor (D-A) molecular framework that can modulate the fluorescence emission intensity through a fast photoinduced intramolecular electron transfer (PET) process. The emissio
The surfactant-promoted cross-coupling reactions of arylboronic acids with carboxylic anhydrides or acyl chlorides in water
Xin, Bingwei,Zhang, Yuhong,Cheng, Kai
, p. 1970 - 1978 (2008/02/12)
The palladium(II) chloride catalyzed cross-coupling of arylboronic acids with carboxylic anhydrides or acyl chlorides in water in the presence of various surfactants is described. The inexpensive and industrially widely used sodium dodecyl sulfate (SDS) was found to be a good promoter of the coupling reaction and aryl ketones were obtained in good yields without the use of phosphine ligands. The reactions were unaffected by the presence of electron-releasing and electron-withdrawing substituents in both the arylboronic acids and carboxylic derivatives and a variety of aryl ketones were obtained under mild conditions in air. Georg Thieme Verlag Stuttgart.
TPA-induced up-regulation of activator protein-1 can be inhibited or enhanced by analogs of the natural product curcumin
Weber, Waylon M.,Hunsaker, Lucy A.,Gonzales, Amanda M.,Heynekamp, Justin J.,Orlando, Robert A.,Deck, Lorraine M.,Vander Jagt, David L.
, p. 928 - 940 (2007/10/03)
The activator protein-1 (AP-1) family of transcription factors, including the most common member c-Jun-c-Fos, participates in regulation of expression of numerous genes involved in proliferation, apoptosis, and tumorigenesis in response to a wide array of stimuli including pro-inflammatory cytokines, growth factors, stress, and tumor promoters. A number of plant polyphenols including curcumin, a yellow compound in the spice turmeric, have been shown to inhibit the activation of AP-1. Curcumin is a polyphenolic dienone that is potentially reactive as a Michael acceptor and also is a strong anti-oxidant. Multiple activities reported for curcumin, including inhibition of the stress-induced activation of AP-1, have been suggested to involve the anti-oxidant properties of curcumin. In the present study, a library of analogs of curcumin was screened for activity against the TPA-induced activation of AP-1 using the Panomics AP-1 Reporter 293 stable cell line which is designed for screening potential inhibitors. Numerous analogs were identified that were more active than curcumin, including analogs that were not anti-oxidants and analogs that were not Michael acceptors. Clearly, anti-oxidant activity or reactivity as a Michael acceptor is not an essential feature of active compounds. In addition, a number of analogs were identified that enhanced the TPA-induced activation of AP-1. The results from screening were confirmed using BV-2 microglial cells where curcumin and analogs were shown to inhibit LPS-induced COX-2 expression; analogs identified as more potent than curcumin in the screening assay were also more potent than curcumin in preventing COX-2 expression.
Anti-oxidant activities of curcumin and related enones
Weber, Waylon M.,Hunsaker, Lucy A.,Abcouwer, Steve F.,Deck, Lorraine M.,Vander Jagt, David L.
, p. 3811 - 3820 (2007/10/03)
The natural product curcumin (diferuloylmethane, 1,7-bis(4-hydroxy-3- methoxyphenyl)-1,6-heptadiene-3,5-dione), obtained from the spice turmeric, exhibits numerous biological activities including anti-cancer, anti-inflammatory, and anti-angiogenesis activities. Some of these biological activities may derive from its anti-oxidant properties. There are conflicting reports concerning the structural/electronic basis of the anti-oxidant activity of curcumin. Curcumin is a symmetrical diphenolic dienone. A series of enone analogues of curcumin were synthesized that included: (1) curcumin analogues that retained the 7-carbon spacer between the aryl rings; (2) curcumin analogues with a 5-carbon spacer; and (3) curcumin analogues with a 3-carbon spacer (chalcones). These series included members that retained or were devoid of phenolic groups. Anti-oxidant activities were determined by the TRAP assay and the FRAP assay. Most of the analogues with anti-oxidant activity retained the phenolic ring substituents similar to curcumin. However, a number of analogues devoid of phenolic substituents were also active; these non-phenolic analogues are capable of forming stable tertiary carbon-centered radicals.
Reactions in Strongly Basic Media. Part 10. Base-catylysed Isomerisation of Z- to E-substituted Chalcones
Bowden, Keith,Duah, Christiana K.,Ranson, Richard J.
, p. 109 - 112 (2007/10/02)
The rate coefficients for the methoxide-catalysed isomerisation of substituted (Z)-chalcones have been measured in methanolic dimethyl sulfoxide (DMSO) at 30.0 deg C, as well as for (Z)-chalcone at several temperatures.The reactions are first order in substrate and base.Further, log k1 for the reaction of (Z)-chalcone and (Z)-4-nitrochalcone correlate with an acidity function, Ha, having slopes equal to 0.53 and 0.45, respectively.The effect of substitution has been assessed using the Hammett equation, with ρ equal to 1.99 for the β-phenyl group and 1.93 for the benzoyl group.For the (Z)-chalcone, the enthalpy and entropy of acti vation are 14.2 kcal mol-1 and -14 cal mol-1 K-1, respectively, and the kinetic solvent isotope effect, k2MeOD/k2MeOH, is ca. 2.0.The rate coefficients for the amine-catalysed isomerisation of (Z)-chalcone and (Z)-4-nitrochalcone in DMSO have been measured at 30.0 deg C.The amino bases are a series of secondary aliphatic amines and the Bronstedt coefficients, β, are given as 0.39 and 0.38, respectively.The isomerisation is considered to proceed by rate-determining attack of the base at the β-carbon of the (Z)-chalcone to form a carbanion.The "cis"-conformer of the carbanion then rotates to form the "trans"-conformer, which eliminates the base to give the (E)-chalcone.
