DFT Study on the Antioxidant Activity of a Modeled p-Terphenyl Derivative  

作　　者：王传铭 潘蓄林 

机构地区：[1]Department of Biology, Honghe University [2]School of Life Science, Yunnan University [3]School of Mathematics and Statistics, Yunnan University

出　　处：《Chinese Journal of Structural Chemistry》2012年第6期894-902,共9页结构化学（英文）

基　　金：Supported by NNSFC(10901135,11171293);Natural Science Foundation of Yunnan Province(2008CD081,2010CC003);Educational Commission of Yunnan Province(2011Y296);Foundation of Honghe University(2010PY0104,10XJY113)

摘　　要：Relationships between the structure characteristics of natural p-terphenyl com- pounds isolated from three edible mushrooms （Thelephora ganbajun, Thelephora aeronautical, and Boletopsis grisea） indigenous to China and their mechanism of antioxidant activity were studied. Geometry structures of terphenyl molecule and four corresponding radicals, bond dissociation energy （BDE）, frontier orbitals （HOMO and LUMO） and single electron density were calculated using DFT methods （B3LYP/6-311G＊＊）. The computational results which are consistent with the experimental data well show that terphenyl molecule scavenges DPPH radical by hydrogen abstract mechanism and the high antioxidant activity depends on the substitution position of hydroxyls. Two active 7-, 8-hydroxyls facilitate the hydrogen abstraction due to the intramolecular hydrogen bond and the resonance effect makes 4-hydroxyl radical more stable.Relationships between the structure characteristics of natural p-terphenyl com- pounds isolated from three edible mushrooms （Thelephora ganbajun, Thelephora aeronautical, and Boletopsis grisea） indigenous to China and their mechanism of antioxidant activity were studied. Geometry structures of terphenyl molecule and four corresponding radicals, bond dissociation energy （BDE）, frontier orbitals （HOMO and LUMO） and single electron density were calculated using DFT methods （B3LYP/6-311G＊＊）. The computational results which are consistent with the experimental data well show that terphenyl molecule scavenges DPPH radical by hydrogen abstract mechanism and the high antioxidant activity depends on the substitution position of hydroxyls. Two active 7-, 8-hydroxyls facilitate the hydrogen abstraction due to the intramolecular hydrogen bond and the resonance effect makes 4-hydroxyl radical more stable.

关 键 词：TERPHENYL ANTIOXIDANT free radical conjugative effect O-H bond dissociation energy 

分 类 号：O621.1[理学—有机化学]