水液相下依达拉奉与超氧阴离子自由基反应的密度泛函理论

Density Functional Theory of Reaction between Edaravone and Superoxide Anion Free Radical in Aqueous Liquid Phase

采用密度泛函理论(DFT)的M06-2X和MN15方法,结合自洽反应场理论的SMD(solvationmodeldensity)模型方法,研究水液相下依达拉奉(Eda)消除超氧阴离子自由基(O_(2)^(·-))的反应机理.结果表明:Eda消除O_(2)^(·-)的反应有3个通道,分别是O_(2)^(·-)抽H原子、O_(2)^(·-)加成到不饱和C和单电子从Eda向O_(2)^(·-)转移;O_(2)^(·-)抽H反应的最低能垒为12.2kJ/mol,O_(2)^(·-)加成反应的最低能垒为110.2kJ/mol,单电子从Eda向O_(2)^(·-)转移的能垒为408.5kJ/mol,抽H反应最具优势.水液相下Eda消除O_(2)^(·-)的反应主要在抽H通道实现,因此Eda可作为O_(2)^(·-)自由基清除剂.

We studied the reaction mechanism of Edaravone(Eda)scavenging superoxide anion free radical(O_(2)^(·-))in aqueous liquid phase by using M06-2X and MN15 methods of DFT(density functional theory)and SMD(solvation model density)model method of self-consistent reaction field theory.The results show that the reaction of Eda scavenging O_(2)^(·-)has three channels,which are extraction of H atom by O_(2)^(·-),addition of O_(2)^(·-)to unsaturated C and single electron transfer from Eda to O_(2)^(·-).The lowest energy barrier of O_(2)^(·-)extracting H reaction is 12.2 kJ/mol,the lowest energy barrier of O_(2)^(·-)addition reaction is 110.2 kJ/mol,the energy barrier of single electron transfer from Eda to O_(2)^(·-)is 408.5 kJ/mol,and the reaction of extracting H has the most advantage.The reaction of Eda scavenging O_(2)^(·-)is mainly achieved in channel of extracting H in aqueous liquid phase,and Eda can be used as O_(2)^(·-)free radical scavenger.