脉冲辐解研究茶多酚4个组分清除羟自由基机理

采用脉冲电子辐解瞬态吸收光谱法 ,在pH 7的磷酸缓冲水溶液中测定茶多酚 4个组分表没食子儿茶素没食子酸酯 (EGCG)、表儿茶素没食子酸酯 (ECG)、表没食子儿茶素 (EGC)和表儿茶素 (EC)的清除羟自由基速率常数分别为 1 .5× 1 0 10 ,1 .4× 1 0 10 ,9.7× 1 0 9和 9.2× 1 0 9dm3 ·mol-1·s-1,并提出了EGCG和ECG在清除羟自由基的过程中存在一个脱没食子酸基团的机理     

Reactions of tea polyphenol four constituents with hydroxyl radical: A pulse radiolytic study

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Oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate

The oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate has been studied by laser flash photolysis and pulse radiolysis. The formation and decay processes of transient species of podophyllotoxin and its derivatives have been observed, and a series of rate constants for the formation and decay of transient species have been determined. It has been found that there is a light (UV) sensitive group on the C-4 of podophyllotoxin and two light (UV) sensitive groups on the C-4 and C-4' of 4'-demethylepipodophyllotoxin.     

过硫酸钠氧化鬼臼毒素及其衍生物的机理研究

用激光光解和脉冲辐解技术对过硫酸钠氧化鬼臼毒素及其衍生物水溶液的机理进行了研究。观察了各种瞬态粒子的生成和衰变过程,并测定了各种瞬态粒子的生成和衰变速率常数,发现鬼臼毒素的C-4位,去甲表鬼臼毒素的C-4位和C-1基团的C-4′位都是很活泼的基团,具有强光敏性,并分析其反应机理和分子结构的关系。