2950-01-8Relevant academic research and scientific papers
Synthesis of Oligomers by Oxidative Dehydrogenation of Dihydric Phenols and Quinones with 3,3′,5,5′-Tetra-tert-butyl-trans-stilbenequinone
Nigmatullin,Akhmadullin,Gazizov,Akhmadullina,Mukmeneva,Hoang
, p. 1319 - 1324 (2018)
Oxidative dehydrogenation of pyrocatechol and 1,4-benzoquinone with 3,3′,5,5′-tetra-tert-butyl-trans-stilbenequinone as oxidant afforded oligomeric polyhydroquinones and polyquinones. Appropriate reaction conditions have been found, and the resulting olig
Acetyl chloride - 3,5-di(tert-butyl)-4-hydroxy-N,N-dimethylbenzylamine salt in the benzylation of organic and inorganic sulfur-containing compounds
Gorbunov, D. B.,Voznesenskii, V. N.,Ershov, V. V.,Nikiforov, G. A.
, p. 93 - 97 (1994)
The reactions of the quaternary acylammonium salt formed on treatment of 3,5-di-tert-butyl-4-hydroxy-N,N-dimethylbenzylamine with acetyl chloride, with various organic and inorganic sulfur-containing compounds were studied.The possibility of using this salt for the introduction of a sterically hindered phenol moiety in various sulfur-containing compounds was shown. - Key words: sterically hindered phenols, quaternary ammonium salts, benzylation, thiourea.
Synthesis of 3,3′,5,5′-Tetra-tert-butyl-4,4′-stilbenequinone and Its Catalytic Activity in the Liquid-Phase Oxidation of Inorganic Sulfides
Hoang,Akhmadullin,Akhmadullina, F. Yu.,Zakirov,Akhmadullina,Gazizov
, p. 1008 - 1013 (2018)
The oxidation of 2,6-di-tert-butyl-4-methylphenol with hydrogen peroxide in the presence of potassium iodide gave 3,3′,5,5′-tetra-tert-butyl-4,4′-stilbenequinone which catalyzed liquid-phase oxidation of sodium sulfide with oxygen more efficiently than di
New hydroxystilbenoid derivatives endowed with neuroprotective activity and devoid of interference with estrogen and aryl hydrocarbon receptor-mediated transcription
Villalonga-Barber, Carolina,Meligova, Aggeliki K.,Alexi, Xanthippi,Steele, Barry R.,Kouzinos, Constantinos E.,Screttas, Constantinos G.,Katsanou, Efrosini S.,Micha-Screttas, Maria,Alexis, Michael N.
experimental part, p. 339 - 351 (2011/02/27)
We have synthesized a series of new (E) stilbenoid derivatives containing hydroxy groups at ring positions identical or similar to those of trans-resveratrol and bearing one or two bulky electron donating groups ortho to 4′-OH and we have evaluated their neuroprotective activity using glutamate-challenged HT22 hippocampal neurons to model oxidative stress-induced neuronal cell death. The most active derivatives, 5-{(E)-2-[3,5-bis(1- ethylpropyl)-4-hydroxyphenyl]ethenyl}-1,3-benzenediol (2), 5-[(E)-2-(3,5-di- tert-butyl-4-hydroxyphenylethenyl)]-1,3-benzenediol (4) and 5-{(1E,3E)-4-[3,5- bis(1-ethylpropyl)-4-hydroxyphenyl]-1,3-butadienyl}-1,3-benzenediol (6), had EC50 values of 30, 45 and 12 nM, respectively, and were ca. 100 to 400-fold more potent than resveratrol. Derivatives 2, 4 and 6 lacked cytotoxic activity against HT22 cells and estrogen receptor agonist or antagonist activity in estrogen response element-dependent gene expression and in estrogen-dependent proliferation of MCF-7 human breast cancer cells. In addition, they were incapable of interfering with aryl hydrocarbon receptor-mediated xenobiotic response element-dependent gene expression. Derivatives 2, 4 and 6 might assist in the development of lead candidates against oxidative stress-driven neurodegenerative diseases that will not increase endocrine cancer risk nor affect drug activation and detoxification mechanisms.
Reduction of 4,4′-stilbenequinone and 4,4′-diphenoquinone upon reaction with photogenerated radicals
Goerner, Helmut
experimental part, p. 1202 - 1207 (2011/09/20)
The properties of 3,3′,5,5′-tetra-tert-butyl-4,4′- stilbenequinone (StQ) were studied by photochemical means. Acetone, acetophenone or benzophenone was photolyzed in the presence of both StQ and a donor, such as alcohols or triethylamine. This initiated reaction of a ketyl radical with StQ to form a semiquinone radical and eventually induce a permanent bleaching due to conversion of StQ to 4,4′-dihydroxystilbene (StQH2). The quantum yield of conversion of StQ to StQH2 increases with the donor concentration. Similar effects were found for the ketone-sensitized radical-induced conversions of the analogous diphenoquinone to the reduction product, diphenol.
Practical process for the air oxidation of cresols: Part A. Mechanistic investigations
Barton, Benita,Logie, Catherine G.,Schoonees, Barbara M.,Zeelie, Bernard
, p. 62 - 69 (2012/12/24)
The catalytic air oxidation of p-cresol and 2,6-di-tert-butyl-4- methylphenol to the corresponding benzaldehydes was investigated to determine the mechanism at work in these oxidation reactions. A number of intermediates and byproducts, mainly in the form of dimers, were observed during the course of the reactions, and their structures were elucidated by spectroscopic and chromatographic methods. The existence of these compounds in the reaction mixtures, and their proposed methods of formation, provided further insight into the mechanism involved in these oxidations.
Thermal decomposition of 2,6-di-tert-butyl-4-dimethylaminomethylphenol
Zakharova,Khismatullina,Ivanov
, p. 1787 - 1789 (2007/10/03)
Products of thermolysis of 2,6-di-tert-butyl-4-dimethylaminomethylphenol were determined qualitatively and quantitatively by GLC, UV, and 1H NMR methods. The kinetics of the reaction was studied. The thermolysis products were studied as the inhibitors in thermopolymerization of monomers.
Oxidative Dehydrogenation of Sterically Hindered para-Substituted Phenols with 3,3′,5,5′-Tetra-tert-butyl-4,4′-diphenoquinone
Mukmeneva,Bukharov,Kadyrova,Zharkova,Gorshunova,Fazlieva
, p. 1486 - 1489 (2007/10/03)
The reactivity of 4-methyl-, 4-mercapto-, and 4-methoxymethyl-2,6-di-tert-butylphenols in oxidative dehydrogenation with 3,3′,5,5′-tetra-tert-butyl-4,4′-diphenoquinone was studied, and the structure of products was determined.
Stabilizer of isoprene rubber and thermoplastic compositions on its base
Fazlieva,Mukmeneva,Bukharov,Vol'fson
, p. 1252 - 1253 (2007/10/03)
The stabilizing efficiency was studied of the products of oxidative dehydration of 4-methyl-2,6-di-tert-butylphenol with 3,3′,5,5′-tetra-tert-butyl-4,4′-diphenoquinone in SKI-3 synthetic isoprene rubber and a thermoplastic composition based on SKI-3 and polypropylene.
Electroorganic Reactions. 31. Quinonemethide Radical-Anions and Dianoins: Their Cathodic Generation and Reactivity
Goulart, Marilia O. F.,Utley, James H. P.
, p. 2520 - 2525 (2007/10/02)
The cathodic reactions of a number of relatively stable quinonemethides have been examined in detail by cyclic voltammetry, controlled potential coulometry, and rigorous product analysis following preparative-scale electrolyses.The results of cyclic voltammetric experiments differ in some respects from those of earlier polarographic work.The lifetimes of the electrogenerated radical-anions and dianions, in the absence of added electrophile, are governed by steric hindrance.Hindered intermediates are relatively long-lived yet hydrogenate in the presence of proton donor and alkylate in the presence of methyl iodide.Less hindered analogue efficiently and rapidly dimerize, at carbon, with concomitant protonation or O-methylation depending on added electrophile.The ambident cathodically generated nucleophiles alkylate at both carbon and oxygen, and the competition is crucially dependent on the cation (Bu4N+ or Li+).Fuchsone 3 gives reduction products which vary with initial concentration and on the presence, or otherwise, of oxygen.Efficient reaction between oxygen and triarylmethyl radicals generated, e.g., from 3 has been demonstrated.
