The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Alexander V. Butin - One of the best experts on this subject based on the ideXlab platform.
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Furan ring opening indole ring closure recyclization of 2 2 aminophenyl Furans into 2 2 oxoalkyl indoles
Tetrahedron, 2012Co-Authors: Arkady S Pilipenko, Vladimir V Melchin, Dmitry A Cheshkov, Alexander V. Butin, Igor V. TrushkovAbstract:The acid-catalyzed rearrangement of 5-alkyl-2-[2-(sulfonylamino)phenyl]Furans into 2-(2-oxoalkyl)indoles is described. When the N-sulfonyl group in the starting compounds was displaced by an N-acyl group, the corresponding indoles were not formed under the same reaction conditions due to the in situ indole deacylation and decomposition. The presence of an alkyl group at the C5 position of the Furan ring is also crucial for the efficiency of the process. The discussed rearrangement provides a simple and efficient approach to 2-(2-oxoalkyl)indoles.
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Furan as a 1 3 diketone equivalent the second type Furan recyclization applied to indole synthesis
Tetrahedron Letters, 2006Co-Authors: Alexander V. ButinAbstract:A new approach for the synthesis of indole derivatives based on protolytic recyclization of 2-alkyl-5-(2-tosylaminoaryl)-Furans is described. The Furan ring in this unusual transformation formally serves as a 1,3-diketone equivalent.
Girolamo Cirrincione - One of the best experts on this subject based on the ideXlab platform.
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synthesis and antitumor activity of 2 5 bis 3 indolyl Furans and 3 5 bis 3 indolyl isoxazoles nortopsentin analogues
Bioorganic & Medicinal Chemistry, 2010Co-Authors: Patrizia Diana, Anna Carbone, Paola Barraja, Gerhard Kelter, Heinzherbert Fiebig, Girolamo CirrincioneAbstract:Abstract A series of novel 2,5-bis(3′-indolyl)Furans and 3,5-bis(3′-indolyl)isoxazoles were synthesized as antitumor agents. The antiproliferative activity was evaluated in vitro toward diverse human tumor cell lines. Initially 5 isoxazoles and 3 Furan derivatives were tested against a panel of 10 human tumor cell lines and the most active derivatives 3c and 4a were selected to be evaluated in an extended panel of 29 cell lines. By exhibiting mean IC50 values of 17.4 μg/mL (3a) and 20.5 μg/mL (4c), in particular 4c showed a high level of tumor selectivity toward the 29 cell lines.
Huanfeng Jiang - One of the best experts on this subject based on the ideXlab platform.
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copper catalyzed c o bond formation an efficient one pot highly regioselective synthesis of Furans from 2 furyl carbene complexes
Organic Letters, 2013Co-Authors: Hua Cao, Haiying Zhan, Jinghe Cen, Jingxin Lin, Yuanguang Lin, Qiuxia Zhu, Huanfeng JiangAbstract:A convenient one-pot Cu(I)-catalyzed strategy for regioselective synthesis of trisubstituted Furan derivatives has been developed via (2-furyl) carbene complexes. This process has opened a new synthetic route to a variety of α-carbonyl Furans using air as the oxidant affording Furans in good yields.
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a novel entry to functionalized benzoFurans and indoles via palladium 0 catalyzed arylative dearomatization of Furans
Organic Letters, 2012Co-Authors: Biaolin Yin, Congbi Cai, Guohui Zeng, Ruoqi Zhang, Huanfeng JiangAbstract:A novel entry to functionalized benzoFurans and indoles from Furans in moderate to good yields has been developed. This protocol involves palladium(0)-catalyzed dearomatizing intramolecular arylation of the Furan ring, formation of a π-allylic palladium complex, Furan ring opening, and a β-hydride elimination sequence.
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sequential synthesis of Furans from alkynes successive ruthenium ii and copper ii catalyzed processes
Angewandte Chemie, 2009Co-Authors: Huanfeng Jiang, Min Zhang, Helfried Neumann, Matthias Beller, Pierre H DixneufAbstract:Step in time: 2,5-Disubstituted Furans can be prepared from terminal alkynes in one pot using two successive catalytic reactions (see scheme; p-TSA = para-toluenesulfonic acid). First, a 1,3-dienyl alkyl ether is produced by the dimerization of a terminal alkyne and addition of an alcohol catalyzed by [RuCp*(NCMe)(3)][PF(6)]. Then, consecutive hydrolysis and cyclization catalyzed by CuCl(2) provides the 2,5-disubstituted Furan.
Giuseppe R Palmese - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of thermosetting Furan based epoxy systems
Macromolecules, 2014Co-Authors: John J La Scala, Joshua M Sadler, Giuseppe R PalmeseAbstract:Renewable alternatives to petroleum-based thermosetting polymers have drawn significant attention due to potential positive economic and ecological impact. New materials should mimic the rigid, phenylic structure of incumbent high-performance thermoset monomers. Furans derived from cellulose and hemicellulose are promising candidates for phenyl replacement. The synthesis of Furan-based diepoxies is challenging, and direct property comparisons of thermosets prepared using Furanyl and phenyl-based epoxy monomer analogues are required. In this work, analogous Furanyl-based and phenyl-based diepoxy monomers were synthesized, and thermosets were prepared using amine curing agents. A structure–property study showed that Furan-based polymers possess improved Tg (Δ = 8–16 °C) and improved glassy modulus (Δ = 0.1 to 0.6 GPa) relative to their phenylic analogues. The Furan ring has thus been demonstrated to be a viable building block for renewable high-performance epoxies, with potential for application in other th...
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room temperature self healing thermoset based on the diels alder reaction
ACS Applied Materials & Interfaces, 2013Co-Authors: Purnomo A Pratama, Amy M. Peterson, Majid Sharifi, Giuseppe R PalmeseAbstract:A self-healing epoxy-amine thermoset based on the compatible functionalization of the thermoset and encapsulated healing agent has been successfully developed. Healing of the thermoset resulted from the reaction of Furans in the thermoset and multimaleimides (MMIs) in the healing agent solution. The healing agent, MMI dissolved in phenyl acetate, was encapsulated using a urea-formaldehyde encapsulation method. Autonomic healing of the thermoset was achieved by incorporating microcapsules filled with the healing agent solution within a Furan-functionalized epoxy-amine thermoset. The resulting self-healing thermoset recovered 71% of its initial load after fracture.
Imre Blank - One of the best experts on this subject based on the ideXlab platform.
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formation of Furan and methylFuran by maillard type reactions in model systems and food
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Anita Limacher, Josef Kerler, Tomas Davidek, Frank Schmalzried, Imre BlankAbstract:The formation of Furan and 2-methylFuran was studied in model systems based on sugars and selected amino acids. Both compounds were preferably formed under roasting conditions in closed systems yielding up to 330 µmol of Furan and 260 µmol of 2-methylFuran per mol of precursor. The amounts obtained under pressure cooking conditions were much lower, usually below 20 µmol/mol, except for 2-furaldehyde, which yielded 70−100 µmol/mol of Furan. Labeling studies indicated two major formation pathways for both Furans: (i) from the intact sugar skeleton and (ii) by recombination of reactive C2 and/or C3 fragments. Under roasting conditions in the absence of amino acids, Furan was mainly formed from the intact sugar skeleton. Formic and acetic acid were identified as byproducts of sugar degradation, indicating the split off of C1 and/or C2 units from hexoses. The presence of alanine, threonine, or serine promoted Furan formation by the recombination of C2 fragments, such as acetaldehyde and glycolaldehyde, which m...
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formation of Furan and methylFuran by maillard type reactions in model systems and food
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Anita Limacher, Josef Kerler, Tomas Davidek, Frank Schmalzried, Imre BlankAbstract:The formation of Furan and 2-methylFuran was studied in model systems based on sugars and selected amino acids. Both compounds were preferably formed under roasting conditions in closed systems yielding up to 330 micromol of Furan and 260 micromol of 2-methylFuran per mol of precursor. The amounts obtained under pressure cooking conditions were much lower, usually below 20 micromol/mol, except for 2-furaldehyde, which yielded 70-100 micromol/mol of Furan. Labeling studies indicated two major formation pathways for both Furans: (i) from the intact sugar skeleton and (ii) by recombination of reactive C(2) and/or C(3) fragments. Under roasting conditions in the absence of amino acids, Furan was mainly formed from the intact sugar skeleton. Formic and acetic acid were identified as byproducts of sugar degradation, indicating the split off of C(1) and/or C(2) units from hexoses. The presence of alanine, threonine, or serine promoted Furan formation by the recombination of C(2) fragments, such as acetaldehyde and glycolaldehyde, which may originate from both sugars and amino acids. In aqueous solution, about half of Furan was generated by the recombination of sugar fragments. 2-MethylFuran was preferably formed in the presence of amino acids by aldol-type reactions of C(2) and C(3) fragments with lactaldehyde as a key intermediate, the Strecker aldehyde of threonine. The total Furan levels in cooked vegetables were increased by spiking with hexoses. However, in pumpkin puree, only about 20% of Furan was formed from sugars, preferably from the intact carbon skeleton.
