Premium
The Partition Coefficient of Protonated Antihistamines. Its calculation and interpretation in terms of hydrophobic fragmental constants
Author(s) -
Testa Bernard,
MursetRossetti Livia
Publication year - 1978
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19780610724
Subject(s) - chemistry , partition coefficient , protonation , partition (number theory) , thermodynamics , analytical chemistry (journal) , computational chemistry , stereochemistry , chromatography , organic chemistry , combinatorics , mathematics , ion , physics
The octanol/water partition coefficient ( P + ) of nineteen monoprotonated antihistaminic drugs has been measured. These values are compared with the partition coefficient ( P ) of the neutral molecules, suggesting the variations in partition coefficient seen upon protonation to obey simple rules. Indeed, the (log P –log P + ) values are multiples of a constant term 0.28 ( Rekker 's ‘magic constant’ c M [6]), each functional group contributing with a fixed incremental value. The incremental values are confirmed by multiple linear regression analysis, and their physical significance is discussed.