Involvement of lactones in the formation of 6-hydroxydopa and 6-hydroxyhydrocaffeic acid during oxidation of dopa and hydrocaffeic acid

被引：7

作者：

Li, JY ^{[1
]}

Zhang, FJ ^{[1
]}

Christensen, BM ^{[1
]}

机构：

[1] UNIV WISCONSIN,SCH PHARM,MADISON,WI 53706

来源：

JOURNAL OF ELECTROANALYTICAL CHEMISTRY | 1996年 / 412卷 / 1-2期

基金：

美国国家卫生研究院;

关键词：

oxidation; reduction; lactones; 6-hydroxydopa; 6-hydroxyhydrocaffeic acid; dopa; hydrocaffeic acid;

D O I：

10.1016/0022-0728(96)04602-5

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Detailed oxidation/reduction pathways that lead to the formation of 2,4,5-trihydroxyphenolic compounds during the oxidation of dopa, hydrocaffeic acid and N-acetyldopa are described. Data suggest that (i) oxidation of dopa, hydrocaffeic acid and N-acetyldopa results in the formation of their corresponding o-quinones, (ii) the o-quinones undergo intramolecular nucleophilic addition through the side chain carboxy group to form lactones under weak acid conditions, (iii) oxidation of the lactones produces their corresponding lactone-o-quinones, (iv) the lactone-o-quinones, once formed, undergo rapid hydrolysis that leads to the formation of 2-hydroxy-1,4-benzoquinones (p-quinones) as relatively stable products and (v) reduction of the p-quinones results in the formation of their corresponding 6-hydroxydopa, 6-hydroxyhydrocaffeic acid and N-acetyl-6-hydroxydopa. Data suggest that 6-hydroxydopa also can be produced by direct hydrolysis of dopa-lactone.

引用

页码：19 / 29

页数：11

共 15 条

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