用不同取代基对化学发光物质6-芳基-2-甲基咪唑[1,2-α]吡嗪-3-(7H)酮环(海萤发光的类似物)的芳基位进行取代,形成系列海萤荧光素类似物MIPa-MIPd;并采用B3LYP/6-311+G(d,p)方法,通过电子抽取能(EEP)的计算和自然电荷布居分析(NPA),研究了在气相、二甲亚砜(DMSO)和二甘醇二甲醚(DG)中海萤发光的类似物从阴离子变化到自由基过程中取代基的作用.结果表明:在这个过程中,吲哚在DG中作为取代基(MIPb)时的EEP最小,电荷变化最大,说明这种取代基有利于反应的进行.
A series of 6-aryl-2-methylimidazo[1,2-α]pyrazin-3-(7H)-ketone based derivatives MIPa-MIPd(cypridina luciferin analogues) were investigated using the B3LYP/6-311+G(d,p) method,and we modeled a 6-site replacement by different substituents.The effect of different substitutions on cypridina luciferin analogues in their transition from anions to free radicals was studied by electron extraction potentials(EEP) and natural charge population analysis(NPA) in gas phase,dimethyl sulfoxide(DMSO),and diglyme(DG).The calculated results indicated that MIPb(3-indolyl as the substituent) had a lower EEP and a larger natural charge population change occurred at the MIP moiety in DG when transitioning from the anion to its free radical than in the other solvents.We also showed that 3-indolyl,as a substituent,accelerated the luminescent reaction of MIP.