Is HOMO Energy Level a Good Parameter to Characterize Antioxidant Activity  

作　　者：Hong Yu ZHANG De Zhan CHEN 

机构地区：[1]Department of Biological and Chemical Engineering,Zibo University,Zibo 255091 [2]Department of Chemistry,Shandong Teachers'University,Jinan 250014

出　　处：《Chinese Chemical Letters》2000年第8期727-730,共4页中国化学快报（英文版）

摘　　要：Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between logarithm of free radical scavenging rate constants (1gks) and E-HOMO substantially arises from the correlation between E-HOMO and O-H bond dissociation energies (BDE) of antioxidants. Furthermore, E-HOMO were poorly correlated with the logarithm of relative free radical scavenging rate constants (1gk(3)/k(1)) for various types of antioxidants that possess complex structures (r = 0.5602). So in a broad sense, E-HOMO was not an appropriate parameter to characterize the free radical scavenging activity of antioxidants.Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between logarithm of free radical scavenging rate constants (1gks) and E-HOMO substantially arises from the correlation between E-HOMO and O-H bond dissociation energies (BDE) of antioxidants. Furthermore, E-HOMO were poorly correlated with the logarithm of relative free radical scavenging rate constants (1gk(3)/k(1)) for various types of antioxidants that possess complex structures (r = 0.5602). So in a broad sense, E-HOMO was not an appropriate parameter to characterize the free radical scavenging activity of antioxidants.

关 键 词：AM1 ANTIOXIDANT free radical HOMO energy level O-H bond dissociation energy structure-activity relationship 

分 类 号：O621[理学—有机化学]