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Marialuisa Russo Gabriella Poggi Maria Luisa Navacchia Mila D'Angelantonio Salvatore S Emmi 《Research on Chemical Intermediates》2006,32(2):153-170
Chemical radiolytic oxidation induced by OH addition on 1-(2-furan-2-yl-5-hydroxy-6-hydroxymethyl-[1,3]dioxan-4-yl)-ethan-1,2-diol
(sorbitylfurfural, SF) leads, in the presence of controlled amounts of oxygen, to a permanent functional modification of the
target molecule. The yield of conversion reaches 60% of the starting material. LC-MS analysis allowed the identification,
as final products, of carboxylic acids, butenal and hydroxy-furan derivatives in which the sugar chain remains unbroken, while
the furanic ring is attacked first by OH and then by oxygen, giving in succession an intra-/inter-molecular rearrangement
of the allylperoxyl radicals thus formed. The proposed oxidation of the furanic ring envisages the peroxyl intermediates undergoing
mono- and/or bi-molecular reactions; a reaction path has been outlined and is reported here. The presence of unsaturated bonds
in the final products could provide a further site for radical scavenger activity. Therefore, the fast reaction with O2 and the rearrangement of the produced peroxyl radicals to species, which are likely to be effective OH-capturers, reinforces
the antioxidant ability of SF. 相似文献
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M Russo L Sgariglia M D’Angelantonio S S Emmi 《Research on Chemical Intermediates》2004,30(3):253-267
Ionising radiations, employed in a broad range of dose-rate, together with a complex non-linear computation of reaction mechanisms, allow the determination of boundary values of rate constants concerning sorbitylfurfural (SF) reactivity towards a wide series of oxidant and/or virtually harmful radicals. SF reacts with some radicals (H, SO4-˙, CO3-˙, Br2-˙, CH3˙), produced with both pulse and stationary radiolysis in neutral aqueous solution, having electrophilic and/or oxidative behaviour. The rate constants range from diffusional (k = (7-9) × 109 M-1 s-1) to relatively low values (k = 2 × 105 M-1 s-1). The possibility to observe these reactions, by means of radiolytical techniques, is heavily influenced by dose-rate. A relation between the radical E0NHE and their reactivity with SF is hinted. 相似文献
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