作者:Ooi Wong、Robert Henry McKeown
DOI:10.1002/jps.2600771105
日期:1988.11
Precise partition coefficients in 1-octanol-water at 25 degrees C were determined for three 2-thiobarbituric acids and 14 barbituric acids with a wider range of substituents. The experimental log P values (log Pexp) of barbituric acids were correlated with the carbon number and the branching effect of the C5 substituent(s) by linear regression analysis. The carbon number term makes a major contribution
对于三种具有更广泛取代基的2-硫代巴比妥酸和14个巴比妥酸,在25°C的1-辛醇-水中确定了精确的分配系数。通过线性回归分析,巴比妥酸的实验log P值(log Pexp)与碳原子数和C5取代基的支化作用相关。碳数项对分配系数起主要作用。与先前的报道相比,C5取代基的极性效应的贡献微不足道。确定了烯丙基,苯基和氯取代基的疏水常数(pi),当将这些经验pi值应用于报告的log Pexp值时,得出的预测log P(log Pcalc)值更接近预测值。