ESR spin trap

Bis(isoxazoline) decomposes to a number of products depending on the substitution (77H(6)1599) On photolysis using NiS04, two major products were formed. ESR spin trapping demonstrated the intermediacy of imino and 2-isoxazolinyl radicals (77TL4619). 

ANDERSEN M L, ouTTRUP H and SKIBSTED L H (2000) Potential antioxidants in beer assessed by ESR spin trapping, J Agric Food Chem, 48, 3106-11. 

Absorption of a light quantum leads to an electron-hole pair Eq. (19). The electron reacts with an adsorbed oxygen molecule Eq. (20), and the hole semi-oxidizes a sulfide anion at the surface Eq. (21). Further oxidation of the sulfide anion occurs by O and O2 Eq. (22). The number of Cd ions formed equals that of the sulfate anions The oxidation of illuminated CdS powders was investigated by measuring the consumption and by detecting the superoxide radical,, by an ESR spin trapping method... 

DNA breaks in human MCF-7 cells [65], Damaging effect of menadione was probably mediated by hydroxyl radicals as it was demonstrated by ESR spin-trapping method. The analogs of menadione 2-methylmethoxynaphthoquinone and 2-chloromethylnaphtho-quinone also stimulated DNA damage through the formation of superoxide and other free radicals [66]. Similar effects have been shown for hydroquinone, catechol, benzoquinone, and benzenetriol [67,68]. 

Janzen EG, Towner RA, Haire DL. 1987. Detection of free radicals generated from the in vitro metabolism of carbon tetrachloride using improved esr spin trapping techniques. Free Radic Res Common 3 357-364. 

Spectroscopic evidence for peroxy radical 51 was obtained from ESR. Spin trapping studies monitored by ESR have demonstrated that 02 reacts efficiently with 2-nitrobenzenesulfonyl chloride and results in the formation of the peroxy radical intermediate 51 (equation 88). The 5,5-dimethyl-l-pyrroline-l-oxide (DMPO) spin adduct of 51 shows the hyperfine coupling constants, aN = 1.8 G and aH = 10.1 G. 

Artemisinin (qinghaosu) antimalarial activity, 1309, 1313 biological targets, 1311-13 ESR spin-trapping agents, 1291 Feai) degradation, 1283, 1293, 1295-6 heme adducts, 1298, 1311-12 heterolyhc cleavage of peroxide bond, 1301-2, 1309... 

Mizuta Y, Masumizu T, Kohno M, Mori A, Packer L (1997) Kinetic analysis of the Fenton reaction by ESR-spin trapping. Biochem Mol Biol Int 43 1107-1120 Moody GJ (1964) The action of hydrogen peroxide on carbohydrates and related compounds. Adv Carbohydr Chem Biochem 19 149-179... 

Pryor WA, Prier DG, Church DF. Detection of free radicals from low-temperature ozone-olefin reaction by ESR spin trapping evidence that the radical precursor is a trioxide. J Am Chem Soc 1983 105 2883-2888. 

W. Hiraoka et al., Free-radical reactions induced by OH -radical attack on cytosine-related compounds a study by a method combining ESR, spin trapping and HPLC. Nucleic Acids Res. 18, 1217-1223 (1990)... 

Scheme 3. The Sa2 at Pt(II)-lt by Bu O, generated thermally summary of ESR spin-trapping data (29, 142).

Scheme 5. Summary of ESR spin-trapping experiments (similarly for 2,3,5,6-MC4C6HNO) for the lPt(PPh3)3]-RX reaction (189, 142)...

The reaction of 2,4-dinitrohalobenzenes (F,Cl,Br,I) with the anions of heterocyclic ketene aminals was reported to give arylated products by the S l mechanism. This proposal was based on ESR spectroscopy, ESR spin trapping with nitroso-/-butane and the inhibition of the reaction by FeCl3182. 

Figure 2. Free radical release, measured by means of ESR/spin trapping technique, from micronsized and nano-sized Fe203 particles compared with amosite (asbestos).27...

Figure 3. Effect of MWCNT on a) amount of hydroxyl radicals generated by photolysis of hydrogen peroxide, measured by ESR/spin trapping technique b) amount of superoxide radicals generated by a xantine/xantine oxidase system, measured by UV spectroscopy. Light gray bars no NT, dark gray bars in the presence of NT.31...

Barr DP, Mason RP (1995) Mechanism of radical production from the reaction of cytochrome c with organic hydroperoxides - an ESR spin-trapping investigation. J Biol Chem 270 12709-12716... 

Barr DP, Gunther MR, Deterding LJ et al (1996) ESR spin-trapping of a protein-derived tyrosyl radical from the reaction of cytochrome c with hydrogen peroxide. J Biol Chem 271 15498-15503... 

Highly reactive and short-lived free radicals can react with spin traps to form a stable spin adduct. The resulting spin adduct can be detected and identified by ESR spectroscopy. In our model the radical adduct exits the coronary vasculature via the right heart in aqueous bicarbonate-buffered media. Under these conditions the radical adducted to the spin trap PBN rapidly degrades to products that are undetectable by ESR spin trapping. Kotake and Janzen [127] have recently reported that the lifetime of PBN/"OH adduct is dependent on the pH of the media the half-life of PBN/ OH adduct at pH 6 and 8 were 90 and 10 s, respectively. The PBN/"OH adduct was found to decay via the unimolecular... 

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