56790-59-1Relevant academic research and scientific papers
Modelling the Inhibition of Selenoproteins by Small Molecules Using Cysteine and Selenocysteine Derivatives
Reddy, Kishorkumar M.,Mugesh, Govindasamy
, p. 8875 - 8883 (2019/06/17)
Small molecule-based electrophilic compounds such as 1-chloro-2,4-dinitrobenzene (CDNB) and 1-chloro-4-nitrobenzene (CNB) are currently being used as inhibitors of cysteine- and selenocysteine-containing proteins. CDNB has been used extensively to determine the activity of glutathione S-transferase and to deplete glutathione (GSH) in mammalian cells. Also, CDNB has been shown to irreversibly inhibit thioredoxin reductase (TrxR), a selenoenzyme that catalyses the reduction of thioredoxin (Trx). Mammalian TrxR has a C-terminal active site motif, Gly-Cys-Sec-Gly, and both the cysteine and selenocysteine residues could be the targets of the electrophilic reagents. In this paper we report on the stability of a series of cysteine and selenocysteine derivatives that can be considered as models for the selenoenzyme–inhibitor complexes. We show that these derivatives react with H2O2 to generate the corresponding selenoxides, which undergo spontaneous elimination to produce dehydroalanine. In contrast, the cysteine derivatives are stable towards such elimination reactions. We also demonstrate, for the first time, that the arylselenium species eliminated from the selenocysteine derivatives exhibit significant redox activity by catalysing the reduction of H2O2 in the presence of GSH (GPx (glutathione peroxidase)-like activity), which suggests that such redox modulatory activity of selenium compounds may have a significant effect on the cellular redox state during the inhibition of selenoproteins.
Selenium Blue-α and -β: Turning on the fluorescence of a pyrenyl fluorophore via oxidative cleavage of the Se-C bond by reactive oxygen species
Chen, Wei,Bay, Wan Ping,Wong, Ming Wah,Huang, Dejian
supporting information; scheme or table, p. 3843 - 3846 (2012/08/13)
Rapid oxidation of nonfluorescent pyrenyl-CH2SeAr (Ar = o-nitrophenyl) by hypochlorite yielded pyrenyl-CH2Cl and pyrenyl-CH2OH and turns on blue fluorescence, while slow oxidation of pyrenyl-CH2SeAr with excess
Asymmetric Selenoxide Elimination Leading to Chiral Allenic Sulfones
Komatsu, Naoki,Murakami, Tatsushi,Nishibayashi, Yoshiaki,Sugita, Toshio,Uemura, Sakae
, p. 3697 - 3702 (2007/10/02)
Asymmetric oxidation of some aryl vinyl selenides (3) with Sharpless (A-C), modified Sharpless (D) or Davis oxidants (E-G) resulted in the formation of chiral allenic sulfones 5 of up to 42percent enantiomeric excess (ee) via double asymmetric induction,
Oxidation of Organic Diselenides with Hydrogen Peroxide to Alkane- and Areneseleninic Acids and Selenium-Containing Heterocycles
Kloc, Krystian,Mlochowski, Jacek,Syper, Ludwik
, p. 811 - 814 (2007/10/02)
A convenient way is reported for the oxidation of organic diselenides 1,3 to organoseleninic acids 2,4 which were isolated and identified as pure compounds.Some ortho-substituted phenyl diselenides 3d-f underwent oxidative cyclization, and the selenium-co
BENZENEPEROXYSELENINIC ACIDS - SYNTHESIS AND PROPERTIES
Syper, Ludwik,Mlochowski, Jacek
, p. 207 - 214 (2007/10/02)
Benzeneperoxyseleninic acid (3) and its analogs, 2-nitro and 2,4-dinitrobenzeneperoxyseleninic acids (10, 11), were obtained by oxidation of corresponding arylseleninic acids or diaryldiselenides with hydrogen peroxide.Their chemical properties were studied and rearrangement of 3 to benzeneselenic acid 7 was found as an useful method for preparation of this compound.It was also shown that peroxyseleninic acid 10 can be used as an efficient oxidant in the Baeyer-Villiger transformation of the formyl group into formyloxy one.
Rates of Oxidation of o-Nitrobenzeneselenenyl Compounds by m-Chloroperoxybenzoic Acid and the Rate of Reaction of o-Nitrobenzeneselenol with o-Nitrobenzeneselenenic Acid
Kice, John L.,Chiou, Shishue
, p. 290 - 294 (2007/10/02)
Rate constants for the oxidation of a series of o-nitrobenzeneselenenyl derivatives (Ar = o-O2NC6H4) by m-chloroperoxybenzoic acid (MCPBA) have been measured at 25 deg C in ethanol (compound, kPA (M-1s-1)): ArSeH, 1.1 * 104; ArSeOH, 80; ArSeOSeAr, 12; ArSeOEt, 4; ArSeSeAr, 0.15.The rate constant (kArSeH = 1.0 * 102 M-1s-1) for the reaction of ArSeH with ArSeOH to give ArSeSeAr (eq 3), which is pH independent in acid solution, has also been determined.Significant practical consequences of these and related results include the following: (a) the rate of oxidation of selenol (ArSeH) to selenenic acid (ArSeOH) is enough faster than either the oxidation of ArSeOH to seleninic acid (ArSeO2H) or eq 3 so that oxidation of the selenol with 1 molar equiv of MCPBA gives ArSeOH in high yield; (b) with a weaker oxidant, hydrogen peroxide, the rate of oxidation of the selenol is enough slower than the rate of eq 3 that the diselenide (ArSeSeAr) becomes the almost exclusive product; (c) the rate of oxidation of the diselenide is so much smaller than that of any of the other compounds that its initial oxidation to ArSeOSeAr is far and away the slowest step in its overall oxidation to seleninic acid by excess peracid.
Mechanism of the Oxidation of o-Nitro- and o-Benzoylbenzeneselenenic Acids by Peracids, Hydroperoxides, and Hydrogen Peroxide
Kice, John L.,Chiou, Shishue,Weclas, Ludmilla
, p. 2508 - 2516 (2007/10/02)
The oxidations of o-nitro- (1a) and o-benzoylbenzeneselenenic (1b) acids by peroxybenzoic acids (eq.4), hydroperoxides (eq.2, R=t-Bu or PhCMe2), and hydrogen peroxides (R=H) have been studied kinetically over a range of pH in 60percent dioxane.With the peroxybenzoic acids oxidation of 1a and 1b occurs at comparable rates, is not acid catalyzed, and is believed to take place by a mechanism (eq.7) involving nucleophilic attack by the selenium of the selenenic acid on peroxide oxygen that is analogous to the mechanism for oxidation of alkyl sulfides by peracids.With the hydroperoxides and H2O2 the oxidations are subject to acid catalysis, and the o-benzoyl coumpond (1b) is oxidized ca. 104 times faster than 1a.The much faster rate of oxidation of 1b is due to the fact that it reacts by a mechanism (eq 13) where there is reversible formation of a peroxyhemiketal (4), followed by intramolecular attack of selenium of one of the peroxide oxygens in protonated 4.Such a mechanism is not avalaible to 1a, which therefore must react by much slower bimolecular pathways (eq 10 and 11) that are equivalent to the mechanisms for the acid-catalyzed and uncatalyzed oxidations of alkyl sulfides by hydroperoxides and hydrogen peroxide.At pH>2 the oxidation of 1a by hydrogen peroxide exhibits marked autocatalysis.This is due to equilibrium formation from H2O2 and the oxidation product, o-O2NC6H4SeO2H, of some o-nitroperoxybenzeneselenenic acid, o-O2NC6H2Se(O)OOH, which, like a peroxybenzoic acid, is a much more reactive oxidizing agent for 1a than is hydrogen peroxide itself.Comparison of the previously determined (ref 5) rates of reaction of 1a and 1b with thiols with their rates of oxidation by hydroperoxides suggests that the selenenic acid functionality thought (ref 3) to be an intermediate in the reaction cycle for the enzyme glutathione peroxidase should be consumed under physiological conditions almost exclusively by reaction with glutathione rather than be oxidized further by hydroperoxides to a seleninic acid.
