4792-78-3Relevant articles and documents
Benzo-Fused 1,4-Heterocycles via Dialkyl Carbonate Chemistry
Musolino, Manuele,Aricò, Fabi
supporting information, p. 1770 - 1778 (2019/04/05)
A novel halogen-free synthesis of benzo-fused six-membered 1,4-heterocycles through the chemistry of dialkyl carbonates is reported. Commercially available catechol, 2-aminophenol, and 2-aminothiophenol were reacted first with ethylene carbonate in an autoclave to give O -hydroxyethyl, N -hydroxyethyl, and S -hydroxyethyl derivatives respectively, through a B Al 2 mechanism. Then 2-(2-hydroxyethoxy)phenol and 2-(2-hydroxyethylamino)phenol were cyclized in excellent yields by reaction with dimethyl carbonate (DMC) and DABCO as a bicyclic organic base to give the corresponding benzodioxine and benzoxazine derivative, respectively. Moreover, 2-(2-aminophenylthio)ethanol afforded the benzothiazine derivative in good yield by reaction with DMC with an excess of a strong base such as NaH. The investigation on the cyclization reaction has highlighted that several equilibria are involved leading to the formation of carbonate and carbamate intermediates through B Ac 2 mechanisms. Depending on the reaction conditions employed, these intermediates may undergo either kinetic-controlled ring closure by a B Al 2 mechanism or by-product formation.
Revisiting Hydroxyalkylation of Phenols with Cyclic Carbonates
Kao, Shih-Chieh,Lin, Yi-Ching,Ryu, Ilhyong,Wu, Yen-Ku
supporting information, p. 3639 - 3644 (2019/07/10)
Described is a tetrabutylammonium fluoride-mediated hydroxyalkylation reaction of phenols with cyclic carbonates. This operationally simple method enables the synthesis of a variety of aryl β-hydroxyethyl ethers in good to excellent yields with a very small amount of catalyst loading (0.1–1 mol%). Of particular note is the efficient conversion of aromatic diols and phloroglucinol to the corresponding bis- and tris-hydroxyethylated products. To further showcase the versatility of this protocol, guaifenesin was prepared with a single step by the condensation of guaiacol and glycerol carbonate. We also developed a flow ethoxylation process permitting the continuous synthesis of multiflorol. (Figure presented.).
Harnessing C?H Activation of Benzhydroxamates as a Macrocyclization Strategy: Synthesis of Structurally Diverse Macrocyclic Isoquinolones
Krieger, Jean-Philippe,Ricci, Gino,Lesuisse, Dominique,Meyer, Christophe,Cossy, Janine
supporting information, p. 13469 - 13473 (2016/09/13)
Macrocycles are arising considerable interest in medicinal chemistry. With the goal of harnessing C?H activation reactions for the development of efficient macrocyclization processes, the ruthenium(II)-catalyzed cyclization of O-methyl benzhydroxamates possessing an ω-acetylenic chain was investigated to access new structurally diverse macrocyclic isoquinolones. A slow addition of the substrate and the presence of Cu(OAc)2?H2O as an additive were crucial for the success of the macrocyclization that features an excellent functional-group compatibility, as illustrated by the successful synthesis of a library of 21 macrocyclic isoquinolones of different ring sizes and substitution patterns. These results contribute to significantly highlight the synthetic interest of C?H activation-mediated processes for the synthesis of new macrocyles incorporating heterocyclic scaffolds of potential interest in medicinal chemistry.
The toluene o-xylene monooxygenase enzymatic activity for the biosynthesis of aromatic antioxidants
Donadio, Giuliana,Sarcinelli, Carmen,Pizzo, Elio,Notomista, Eugenio,Pezzella, Alessandro,Di Cristo, Carlo,De Lise, Federica,Di Donato, Alberto,Izzo, Viviana
, (2015/05/05)
Monocyclic phenols and catechols are important antioxidant compounds for the food and pharmaceutic industries; their production through biotransformation of low-added value starting compounds is of major biotechnological interest. The toluene o-xylene monooxygenase (ToMO) from Pseudomonas sp. OX1 is a bacterial multicomponent monooxygenase (BMM) that is able to hydroxylate a wide array of aromatic compounds and has already proven to be a versatile biochemical tool to produce mono- and dihydroxylated derivatives of aromatic compounds. The molecular determinants of its regioselectivity and substrate specificity have been thoroughly investigated, and a computational strategy has been developed which allows designing mutants able to hydroxylate non-natural substrates of this enzyme to obtain high-added value compounds of commercial interest. In this work, we have investigated the use of recombinant ToMO, expressed in cells of Escherichia coli strain JM109, for the biotransformation of non-natural substrates of this enzyme such as 2-phenoxyethanol, phthalan and 2-indanol to produce six hydroxylated derivatives. The hydroxylated products obtained were identified, isolated and their antioxidant potential was assessed both in vitro, using the DPPH assay, and on the rat cardiomyoblast cell line H9c2. Incubation of H9c2 cells with the hydroxylated compounds obtained from ToMO-catalyzed biotransformation induced a differential protective effect towards a mild oxidative stress induced by the presence of sodium arsenite. The results obtained confirm once again the versatility of the ToMO system for oxyfunctionalization reactions of biotechnological importance. Moreover, the hydroxylated derivatives obtained possess an interesting antioxidant potential that encourages the use of the enzyme for further functionalization reactions and their possible use as scaffolds to design novel bioactive molecules.
NOVEL PROCESS FOR THE SYNTHESIS OF PHENOXYETHYL DERIVATIVES
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Page/Page column 22, (2011/09/19)
The present invention provides an improved process for the synthesis of 2-[2- (2,2,2-trifluoroethoxy)phenoxy]ethanol intermediate, its derivatives and/or its pharmaceutically acceptable salts, useful in the synthesis of α-1 adrenoceptor blockers such as silodosin.
Aromatic ethers and process for producing aromatic ethers
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Page 15-16, (2010/02/08)
According to a production process, aromatic ethers are producible by reacting phenols with an oxirane compound with use of an anion exchange resin as a catalyst. According to another production process, aromatic ethers having an alcoholic hydroxyl group are producible by a crystallization-purification step of using a solvent having a solubility parameter ranging from 7.5 to 12.5 for purification by crystallization. Further, according to still another production process, producible are aromatic ethers having an alcoholic hydroxyl group, wherein the content of a metal in the aromatic ethers is less than 100 ppm by mass, and the content of a halogen element in the aromatic ethers is less than 100 ppm by mass.
Process for the synthesis of oligomeric compounds
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, (2008/06/13)
Synthetic processes are provided wherein oligomeric compounds are prepared having phosphodiester, phosphorothioate, phosphorodithioate, or other covalent linkages. Also provided are synthetic intermediates useful in such processes.
Undesirable deprotection of O-TBDMS groups by Pd/C-catalyzed hydrogenation and chemoselective hydrogenation using a Pd/C(en) catalyst
Hattori, Kazuyuki,Sajiki, Hironao,Hirota, Kosaku
, p. 2109 - 2114 (2007/10/03)
In general, O-TBDMS protective groups have been believed to be stable toward Pd/C-catalyzed hydrogenation conditions. In practice, however, frequent and unexpected loss of the TBDMS protective group of a variety of hydroxyl functions occurred under neutral and mild hydrogenation conditions using 10% Pd/C in MeOH. When a 10% Pd/C-ethylenediamine complex catalyst [10% Pd/C(en)] was used instead of 10% Pd/C, the undesirable problem was perfectly overcome and the chemoselective hydrogenation of reducible functionalities leaving intact the TBDMS protective group was achieved.
Studies on quinones. Part. 33. Synthetic approach to podands containing quinone fragments
Valderrama, Jaime A.,Leiva, Hilda,Tapia, Ricardo
, p. 737 - 749 (2007/10/03)
The preparation and oxidative demethylation attempts of podands 3-5, and 9 containing the 2,5-dimethoxyphenyl substituent are described. The reaction of alizarine 13 with chloroethanol afforded compounds 14 and 15. The pathway formation of heterocycle 15 from 14 is proposed. The synthesis of podand 16 containing the cytotoxic 1-hydroxy-9,10-anthraquinone fragment as the terminal groups is reported.
Crown calix[4]arenes, method of preparation and use for selective extraction of caesium
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, (2008/06/13)
PCT No. PCT/FR98/00401 Sec. 371 Date Jan. 27, 1999 Sec. 102(e) Date Jan. 27, 1999 PCT Filed Mar. 2, 1998 PCT Pub. No. WO98/39321 PCT Pub. Date Sep. 11, 1998The invention relates to new calixarenes of formula: in which R1 represents a crown ether chain that includes at least two aryl or cycloalkyl rings, R2 is a hydroxyl or alkoxy group, or the two R2 groups together form a crown ether chain such as R1, and R3 represents a hydrogen atom or an alkyl group. The calixarenes are used to selectively extract caesium from aqueous solutions that notably have high concentrations of sodium.
