77171-98-3Relevant academic research and scientific papers
Screening of a virtual mirror-image library of natural products
Noguchi, Taro,Oishi, Shinya,Honda, Kaori,Kondoh, Yasumitsu,Saito, Tamio,Ohno, Hiroaki,Osada, Hiroyuki,Fujii, Nobutaka
supporting information, p. 7653 - 7656 (2016/07/06)
We established a facile access to an unexplored mirror-image library of chiral natural product derivatives using d-protein technology. In this process, two chemical syntheses of mirror-image substances including a target protein and hit compound(s) allow the lead discovery from a virtual mirror-image library without the synthesis of numerous mirror-image compounds.
Process of separating chiral isomers of chroman compounds and their derivatives and precursors
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Page/Page column 14, (2012/12/13)
The present invention relates to a process of separating chiral isomers of chroman compounds, particularly tocopherols and tocotrienols as well as the esters and intermediates thereof. It has been found that this process allows a separation of the desired isomer with a higher yield and enables the use of the non-desired isomers in a very efficient way. Said process is particularly useful when implemented in an industrial process. Furthermore, it has been found that this process allows using isomer mixtures as they result from traditional industrial synthesis.
Stability and reactivity of aryloxyl radicals derived from a novel antioxidant BO-653 and related compounds. Effects of substituent and side chain in solution and membranes
Watanabe, Akira,Noguchi, Noriko,Fujisawa, Akio,Kodama, Tatsuhiko,Tamura, Kunio,Cynshi, Osamu,Niki, Etsuo
, p. 5438 - 5442 (2007/10/03)
2,3-Dihydro-5-hydroxy-2,2-dipentyl-4,6-di-tert-butylbenzofuran (BO-653) is a novel antioxidant designed as a drug for inhibition of lipid peroxidation in vivo. To understand the dynamics of action of BO-653 as an antioxidant, the effects of substituents and side chains on the stability and reactivity of the BO-653 derived radical were studied and compared with the aryloxyl radicals derived from related compounds including α-tocopherol. The rate constants for the reactions of the aryloxyl radicals with themselves, lipid, hydroperoxide, and ascorbate were measured with a stopped-flow electron spin resonance (ESR) spectroscope equipped with a rapid mixing device. The ortho substituents exerted profound effects on the rate of bimolecular decay reactions and the reaction with ascorbic acid, while the effects on the reactions with methyl linoleate and tert-butyl hydroperoxide were much less significant. The side chain at the 2-position did not exert any effect in organic solution but the two pentyl side chains, when compared with two methyl side chains, diminished the apparent reactivities in the liposomal membranes.
Electron-transfer reactions of alkyl peroxy radicals
Jovanovic, Slobodan V.,Jankovic, Ivana,Josimovic, Ljubica
, p. 9018 - 9021 (2007/10/02)
One-electron-transfer reactions of alkyl peroxy radicals were studied by pulse radiolysis of aqueous solutions. At pH 13, the methyl peroxy radical was found to rapidly, k = 1 × 105-4.9 × 107 s-1, and quantitatively oxidize various organic substrates with E13 = 0.13-0.76 V vs NHE. On the other hand, this radical was unreactive with compounds with E13 ≥ 0.85 V. Consequently, E13 of the methyl peroxy radical is higher than 0.76 V and lower than 0.85 V, which means that E7 is in the range 1.02-1.11 V. At pH 8, the rate constants of the oxidation of four ferrocene derivatives by the alkyl peroxy radicals ranged from 7.1 × 104 M-1 s-1 for ferrocenedicarboxylate (E8 = 0.66 V) to 2.3 × 106 M-1 s-1 for (hydroxymethyl)ferrocene (E8 = 0.42 V). These rate constants were used to evaluate the reduction potential and self-exchange rate of alkyl peroxy radicals in neutral media from the Marcus equation. The calculated E7 = 1.05 V is in excellent agreement with the estimated E7 = 1.02-1.11 V and with one of the perviously published values E7 = 1.0 V, but the value is in excellent agreement higher than the other E7 ～ 0.6 V. It is suggested that the high reorganization energy, λ = 72 kcal mol-1 redox couple originates from the requirement for solvent reorganization due to the solvation of hydroperoxide anion in the transition state. In support of this are the activation parameters of the reaction of the methyl peroxy radical with uric acid. The activation entropy is 9 eu lower at pH 7.3 than it is at pH 13.2, whereas the activation enthalpies are unchanged. The importance of entropy control was verified in the reactions of cyclohexyl peroxy radicals with α- and δ-tocopherol in aerated cyclohexane (ΔH+ ≈ 0 kcal/mol, and ΔS+ = -25 and -26 eu). The implications of these findings on the inactivation of alkyl peroxy radicals in general are discussed.
Electron Transfer Reactions of Halothane-derived Peroxyl Free Radicals, CF3CHClO2.: Measurement of Absolute Rate Constants by Pulse Radiolysis
Moenig, Joerg,Asmus, Klaus-Dieter,Schaeffer, Michel,Slater, Trevor F.,Willson, Robin L.
, p. 1133 - 1138 (2007/10/02)
The halothane-derived peroxyl radical CF3CHClO2. has been generated in aqueous solutions by pulse radiolysis.Absolute rate constants for the reduction of halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) by hydrated electrons, hydrogen atoms, and propan-2-ol free radicals have been determined to be k 1.4E10, 3.8E8, and 7.6E7 l mol-1 s-1, respectively.The predominant product radical CF3CHCl rapidly adds O2, and an estimate of k 1.3E9 l mol-1 s-1, has been obtained for the absolute rate constant of this reaction.The resulting peroxyl radical CF3CHClO2. has been found to react rapidly with a variety of nucleophilic compounds such as 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonate), the phenothiazines promethazine, chlorpromazine, and metiazinic acid, the vitamins C and E, and propyl gallate.The absolute rate constants for these reactions are found to be generally lower than for corresponding reactions of the carbon tetrachloride-derived radical, CCl3O2..
