作者:Yu-Lin Chen、Dave J. Barlow、Xiao-Le Kong、Yong-Min Ma、Robert C. Hider
DOI:10.1039/c2dt31254a
日期:——
As a means to aid in the design of 3-hydroxypyridin-4-ones (HPOs) intended for use as therapeutic Fe3+ chelating agents, a novel methodology has been developed using quantum mechanical (QM) calculations for predicting the iron binding affinities of the compounds (more specifically, their log K1 values). The reported/measured HPO log K1 values were verified through their correlation with the corresponding sum of the compounds’ ligating group pKa values. Using a training set of eleven HPOs with known log K1 values, reliable predictions are shown to be obtained with QM calculations using the B3LYP/6-31+G(d)/CPCM model chemistry (with Bondi radii, and water as solvent). With this methodology, the observed log K1 values for the training set compounds are closely matched by the predicted values, with the correlation between the observed and predicted values giving r2 = 0.9. Predictions subsequently made by this method for a test set of 42 HPOs of known log K1 values gave predicted values accurate to within ±0.32 log units. In order to further investigate the predictive power of the method, four novel HPOs were synthesised and their log K1 values were determined experimentally. Comparison of these predicted log K1 values against the measured values gave absolute deviations of 0.22 (13.87 vs. 14.09), 0.02 (14.31 vs. 14.29), 0.12 (14.62 vs. 14.50), and 0.13 (15.04 vs. 15.17). The prediction methodology reported here is the first to be provided for predicting the absolute log K1 values of iron-chelating agents in the absence of pKa values.
为了帮助设计用于治疗的三羟基吡啶-4-酮(HPOs)作为Fe3+螯合剂,开发了一种新方法,利用量子力学(QM)计算预测化合物的铁结合亲和力(更具体地说,是它们的log K1值)。报告/测量的HPO log K1值通过与相应化合物配位基团pKa值和的总和的相关性得到验证。使用已知log K1值的十一种HPO作为训练集,通过采用B3LYP/6-31+G(d)/CPCM模型化学(以Bondi半径和水作为溶剂)进行QM计算,显示可以获得可靠的预测。使用这种方法,观察到的训练集化合物的log K1值与预测值紧密匹配,观察值与预测值之间的相关性为r2 = 0.9。随后,使用该方法对42种已知log K1值的HPO的预测值在±0.32 log单位内是准确的。为了进一步研究该方法的预测能力,合成了四种新型HPO,并对其log K1值进行了实验测定。将这些预测的log K1值与测量值进行比较,得到的绝对偏差为0.22(13.87对14.09)、0.02(14.31对14.29)、0.12(14.62对14.50)和0.13(15.04对15.17)。此处报告的预测方法是首个在没有pKa值的情况下预测铁螯合剂绝对log K1值的方法。