Reactions of e-(aq), CO2·-, HO·, O2·- and O2(1Δ(g)) with a dendro[60]fullerene and C60[C(COOH)2](n) (n = 2-6)
Bensasson RV, Brettreich M, Frederiksen J, Göttinger H, Hirsch A, Land E, Leach S, McGarvey D, Schönberger H (2000)
Publication Type: Journal article, Original article
Publication year: 2000
Journal
Original Authors: Bensasson R.V., Brettreich M., Frederiksen J., Göttinger H., Hirsch A., Land E.J., Leach S., McGarvey D.J., Schönberger H.
Publisher: Elsevier
Book Volume: 29
Pages Range: 26-33
Journal Issue: 1
DOI: 10.1016/S0891-5849(00)00287-2
Abstract
Using pulse radiolysis and laser flash photolysis, we have investigated the reactions of the deleterious species, e(aq), HO·, O· and O(Δ(g)) with 10 water-soluble cyclopropyl-fused C derivatives including a mono-adduct dendro[60]fullerene (d) and C derivatives based on C[C(COOH)](n = 2-6), some of which are known to be neuroprotective in vivo. The rate constants for reactions of e(aq) and HO· lie in the range 0.5-3.3 x 10 M s. The d and bis-adduct monoanion radicals display sharp absorption peaks around 1000 nm (ε = 7 000-11 500 M cm); the anions of the tris-, tetra-, and penta-adduct derivatives have broader, weaker absorptions. The monohydroxylated radicals have their most intense absorption maxima around 390-440 nm (ε = 1000-3000 M cm). The anion and hydroxylated radical absorption spectra display a blue-shift as the number of addends increases. The radical anions react with oxygen (k ~ 10-10 M s). The reaction of O· with the C derivatives does not occur via an electron transfer. The rate constants for singlet oxygen reaction with the dendrofullerene and eee-derivative in DO at pH 7.4 are k ~ 7 x 10 and ~ 2 x 10 M s respectively, in contrast to ~ 1.2 x 10 M s for the reaction with C in CD. The large acceleration of the rates for electron reduction and singlet oxygen reactions in water is due to a solvophobic process. (C) 2000 Elsevier Science Inc.
Authors with CRIS profile
Michael Brettreich
Lehrstuhl für Organische Chemie II
Andreas Hirsch
Lehrstuhl für Organische Chemie II
Involved external institutions
France (FR)How to cite
APA:
Bensasson, R.V., Brettreich, M., Frederiksen, J., Göttinger, H., Hirsch, A., Land, E.,... Schönberger, H. (2000). Reactions of e-(aq), CO2·-, HO·, O2·- and O2(1Δ(g)) with a dendro[60]fullerene and C60[C(COOH)2](n) (n = 2-6). Free Radical Biology and Medicine, 29(1), 26-33. https://doi.org/10.1016/S0891-5849(00)00287-2
MLA:
Bensasson, René V., et al. "Reactions of e-(aq), CO2·-, HO·, O2·- and O2(1Δ(g)) with a dendro[60]fullerene and C60[C(COOH)2](n) (n = 2-6)." Free Radical Biology and Medicine 29.1 (2000): 26-33.
BibTeX: Download