Hydroxylation and decarboxylation of hydroxybenzoic acids by Fe -chelates
نویسنده
چکیده
4 2 containing FeSO and Na EDTA. EDTA could be replaced by citric acid. In this in vitro system 4hydroxybenzoic acid is hydroxylated to 3,4-dihydroxybenzoic acid (protocatechuic acid) and decarboxylated to hydroquinone. In an analogous reaction 2-hydroxybenzoic acid (salicylic acid) is hydroxylated to 2,3-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid (gentisic acid) and decarboxylated to catechol. Surprisingly the reactions showed Micahelis-Menten saturation kinetics for the products, and this paper is the first description of these reactions. From these data it is also cautioned to use hydroxylation of hydroxybenzoic acids as an indicator of oxidative stress and hydroxyl radicals in biological systems without proper controls.
منابع مشابه
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