肉桂酸类抗氧化剂结构—活性关系研究  

Study on the Structure-activity Relationship of Derivative Antioxidants of Cinnamic Acid

作　　者：张立伟[1] 陈世荣[1] 杨频[1] 

机构地区：[1]山西大学分子科学研究所,太原030006

出　　处：《Chinese Journal of Structural Chemistry》2003年第3期341-345,共5页结构化学（英文）

基　　金：山西省太原市启明星基金资助

摘　　要：利用邻菲罗啉化学发光法研究了中草药有效成分氯原酸、连翘酯甙等肉桂酸类抗氧化剂对HO·的清除作用。量子化学计算[3-21G、B3LYP/6-31G(d)]对实验结果给予了合理的解释。 计算结果显示抗氧化剂形成半醌式自由基前后的能量之差(ΔE)能较好地衡量其活性的高低;抗氧化剂半醌式自由基与邻位取代基形成分子内氢键或通过共振形成邻苯醌可使内能降低,半醌式自由基更稳定;脱氢酚羟基的对位含有给电子取代基团时,可使半醌式自由基易形成并提高其稳定性。Chlorogenic acid, forsythiaside and other derivatives of cinnamic acid are active components of Chinese herbs. In this paper, their scavenging effects on HO are studied by the o-phenathroline chemiluminescent system. The experimental results were elucidated by the quantum chemistry calculation (3-21G, B3LYP). The relationships of structure-activity indicate that DeltaE value, the difference of the energy between the mother molecule and its free radical, is a better parameter to represent the activity of phenolic antioxidants to scavenge free radicals. Forming of intramolecular hydrogen bonding or ortho bezoquinone structure through resonance between the serniquinonoid free radical and ortho group can stabilize the semiquinonoid free radical. The semiquinonoid free radical can be further stabilized by the electron-providing substitutive group in the para position of the H-abstraction hydroxyl.

关 键 词：肉桂酸类抗氧化剂 结构 化学发光 量子化学计算 羟自由基 活性 药物 抗氧化作用 中草药 

分 类 号：O621[理学—有机化学]