pH-metric log P. 4. Comparison of partition coefficients determined by HPLC and potentiometric methods to literature values.
pH-metric log P. 4. Comparison of partition coefficients determined by HPLC and potentiometric methods to literature values.
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pH 测量 log P。 4. 通过 HPLC 和电位方法测定的分配系数与文献值的比较。
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
J. Comer
中科院分区：
文献类型：
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作者：
B. Slater;A. McCormack;Alex Avdeef;J. Comer
在25℃、离子强度0.1 M （KNO3）条件下，用电位法测定了20种化合物的pKa和logp，其中包括6种取代苯酚、2种取代喹啉、n -甲基苯胺、5种巴比妥酸盐衍生物、2种吩噻嗪和其他一些药物分子。用分区高效液相色谱法测定了对数P值。其中三种物质的水溶解度非常低，对于这些物质，水pka是用Yasuda-Shedlovsky技术从甲醇-水溶液中推断出来的。电位法和分区高效液相色谱法测得的log P值均在0.3 ~ 5.4之间，与文献值吻合较好。该研究证明了电位测定技术对不同结构的可电离化合物的普遍适用性。
The pKa and log P of 20 compounds, including six substituted phenols, two substituted quinolines, N-methylaniline, five barbiturate derivatives, two phenothiazines, and several other molecules of pharmaceutical interest, were determined by the potentiometric technique at 25 degrees C and ionic strength 0.1 M (KNO3). The log P values were determined also by partition HPLC. Three of the substances were of very low aqueous solubility, and for these the aqueous pKas were determined by extrapolation from methanol-water solutions using the Yasuda-Shedlovsky technique. Values of log P obtained both by potentiometry and by partition HPLC, which ranged from 0.3 to 5.4, were in very good acordance with literature values. The general applicability of the potentiometric technique to ionizable compounds of diversely varied structures was demonstrated by the study.