Hydrophobicity studies on diadamantanyl derivatives : Comparison between calculated partition coefficients and experimental lipophilicity indices determined by reversed-phase high-performance chromatography and thin-layer chromatography

Abstract

The hydrophobic behaviour of a series of diadamantanyl derivatives with antimicrobial activity was studied by means of reversed-phase high-performance liquid chromatography and thin-layer chromatography. Octanol-water log P values were calculated using Rekker's fragmental procedure. The comparison of all the three data set led to the conclusions that differences between the three partition systems do exist concerning the proximity effect, the ortho effect, the aromatic oxygen fragment and the phenyl ring. These differences were quantified as multiples of Rekker's magic constant and very good correlations were obtained between the chromatographic data and the calculated log P values. The correlation with biological data was in favour of the calculated log P values, indicating that the octanol-water system simulates better the biological processes, in the case of the compounds studied.