Academic Journal
Identification of the Products of Oxidation of Quercetin by Air Oxygen at Ambient Temperature
| العنوان: | Identification of the Products of Oxidation of Quercetin by Air Oxygen at Ambient Temperature |
|---|---|
| المؤلفون: | Igor G. Zenkevich, Anna Yu. Eshchenko, Svetlana V. Makarova, Er G, Yuri G. Dobryakov, Viktor A. Utsal |
| المساهمون: | The Pennsylvania State University CiteSeerX Archives |
| المصدر: | http://www.mdpi.com/1420-3049/12/3/654/pdf?y=1. |
| سنة النشر: | 2007 |
| المجموعة: | CiteSeerX |
| الوصف: | Oxidation of quercetin by air oxygen takes place in water and aqueous ethanol solutions under mild conditions, namely in moderately-basic media (pH ∼ 8-10) at ambient temperature and in the absence of any radical initiators, without enzymatic catalysis or irradiation of the reaction media by light. The principal reaction products are typical of other oxidative degradation processes of quercetin, namely 3,4-dihydroxy-benzoic (protocatechuic) and 2,4,6-trihydroxybenzoic (phloroglucinic) acids, as well as the decarboxylation product of the latter – 1,3,5-trihydroxybenzene (phloroglucinol). In accordance with the literature data, this process involves the cleavage of the γ-pyrone fragment (ring C) of the quercetin molecule by oxygen, with primary formation of 4,6dihydroxy-2-(3,4-dihydroxybenzoyloxy)benzoic acid (depside). However under such mild conditions the accepted mechanism of this reaction (oxidative decarbonylation with formation of carbon monoxide, CO) should be reconsidered as preferably an oxidative decarboxylation with formation of carbon dioxide, CO2. Direct head-space analysis of the gaseous components formed during quercetin oxidation in aqueous solution at ambient temperature indicates that the ratio of carbon dioxide/carbon monoxide in the gas phase |
| نوع الوثيقة: | text |
| اللغة: | English |
| Relation: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.368.1370; http://www.mdpi.com/1420-3049/12/3/654/pdf?y=1 |
| الاتاحة: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.368.1370 http://www.mdpi.com/1420-3049/12/3/654/pdf?y=1 |
| Rights: | Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
| رقم الانضمام: | edsbas.5BF317A9 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |