氧化还原电动势是了解核酸中电荷/电子转移过程以及设计具有新型氧化还原活性的碱基类化合物的重要参数.本文对82个芳香化合物的氧化还原电动势进行理论预测,通过计算值和实验值的比较发现:气相采用B3LYP/6-311++G(2df,2p)//B3LYP/6-31+G(d)方法,液相采用HF-COSMORS/UAHF方法,对运用HF-CPCM/UAHF方法在水相重新优化的构型计算溶剂化能,能有效预测芳香化合物水相氧化还原电动势,该理论方法计算的绝对均方根误差(RMSD)为0.124V.运用该理论方法成功预测了属于芳香化合物的核酸碱基及其代谢物的水相氧化还原电动势.根据预测结果,讨论了核酸中电荷/电子转移过程以及结构改变对设计具有新型氧化还原活性的核酸碱基类化合物的影响.本文为设计具有氧化还原活性的新型核酸碱基类化合物提供了一种理论方法.
Redox potentials are of importance in understanding the charge/electron transfer processes involved in nucleic acids.In this study,the protocol of the B3LYP/6-311++G(2df,2p)//B3LYP/6-31+G(d) in gas phase and the HF-COSMORS/UAHF for the solvation energy calculations at the HF-CPCM/UAHF re-optimized solution geometries in aqueous solution,as implemented in the Gaussian 03 programs,has been established to predict the redox potentials of the aromatic compounds in aqueous solution.In comparison with the 82 experimental redox potentials,the root mean square deviation (RMSD) is only 0.124 V.This scheme has been employed successfully to calculate the redox potentials of various nucleobases and the metabolites.The structural and charge/electron transfer impact on the redox potentials was discussed.The implications to the design of new redox-active nucleobase derivatives were suggested.