摘要
采用密度泛函方法,以键解离焓(EBD)和电离势(EIP)为理论指标评价了硫辛酸清除自由基的活性,发现硫辛酸的EBD和EIP均小于具有抗氧化活性的VC、VE和没食子酸.结合优势构象的几何构型、电荷分布和前线轨道的布居分析结果,发现二硫五元环是分子中的活性区域,电荷密度较大,可以与金属离子螯合;S—S键较长,且EBD和EIP均较小,可以形成自由基而发挥抗氧化作用.羧基部分可以调节分子的水溶性,且电荷密度较大,也可以和金属离子螯合.初步明确了硫辛酸的"结构-抗氧化性"关系.
A DFT method was conducted on lipoic acid to study the ＂structure-antioxidant＂ relationship using bond dissociation enthalpy （EUD） and ionization potential （EIp） as evaluation indicator. The results showed that EBD and EIP was lower than that of Vc,VE and gallic acid. By analyzing the results of the geometry conformation, electronic structures and frontier orloitals, it was found that the doublesulfur-five ring with high electron density was the active center of lipoic acid, which could coordinate with mental iron. The long S--S bond and the low EBb and EIP helped form free radical to show antioxidant activity. The carboxyl with high electron density could coordinate with mental iron too, and regulate the solubility of the title compound.
出处
《分子科学学报》
CAS
CSCD
北大核心
2013年第1期58-61,共4页
Journal of Molecular Science
基金
中国地质大学(武汉)中央高校基本科研业务费专项资金资助项目(CUGL110202)
关键词
硫辛酸
抗氧化性
密度泛函
理论研究
lipoic acid
antioxidant ~ density funtional methods
theoretical study
