Quantification of Lipophilicity of 1,2,4-Triazoles Using Micellar Chromatography

Abstract

High-performance liquid chromatography (HPLC), over-pressured-layer chromatography (OPLC) and thin-layer chromatography (TLC) techniques with micellar mobile phases were proposed to evaluate the lipophilicity of 21 newly synthesized 1,2,4-triazoles, compounds of potential importance in medicine or agriculture as fungicides. Micellar parameters log k m were compared with extrapolated R M 0 values determined from reversed-phase (RP) TLC experimental data obtained on RP-8 stationary phases as well as with log P values (Alog Ps , AClog P , Alog P , Mlog P , KowWin, xlog P 2 and xlog P 3) calculated from molecular structures of solutes tested. The results obtained by applying principal component analysis (PCA) and linear regression showed considerable similarity between partition and retention parameters as alternative lipophilicity descriptors, and indicated micellar chromatography as a suitable technique to study lipophilic properties of organic substances. In micellar HPLC, RP-8e column (Purospher) was applied, whereas in OPLC and TLC, RP-CN plates were applied, which was the novelty of this study and allowed the use of micellar effluents in planar chromatography measurements.

Towards better understanding of lipophilicity: Assessment of in silico and chromatographic logP measures for pharmaceutically important compounds by nonparametric rankings

“…Janicka et al investigated retention behavior of 21 newly synthesized 1,2,4-triazole compounds with antifungal properties and potential importance in medicine and agriculture, under typical reversed-phase and micellar chromatographic conditions [33]. They used thin-layer chromatography, overpressured-layer chromatography (OPLC), as well as high performance liquid chromatography to separate compounds and derive chromatographic lipophilicity indices.…”

“…Also, micellar chromatographic indices are studied alongside with typical RP-TLC derived descriptors. [33]. We paid attention to secure significant diversity of studied compounds and target their pharmacological importance (natural toxins and 1,2,4-triazoles as potent fungicides).…”

“…Lipophilicity data have been taken from the literature [32,33] and are presented in Sections 3.1 and 3.2. We have selected cases providing they cover typical reversed-phase chromatography that combines stationary phases of different polarity [32].…”

Multivariate assessment of lipophilicity scales—computational and reversed phase thin-layer chromatographic indices

“…Many procedures use similarities among computationally estimated values and experimentally derived lipophilicity indices as a criterion to select the best one. Such similarities are most often obtained from hierarchical clustering (HCA) [43,44], principal component analysis [21,23,25,45], or simple correlations based on parametric statistics such as Pearson's correlation coefficient [24,25,44]. The last one is applicable only if the data is normally distributed, which is often not the case.…”

Revisiting thin-layer chromatography as a lipophilicity determination tool. Part IV — A closer look on extrapolation and averaging

“…To mention only several examples, in reversed phase, methanol is used mainly as a modifier [3][4][5][6][7]; however, there are also studies done with acetone [8][9][10], acetonitrile and tetrahydrofurane [11][12][13] or dioxane [14]. Several new papers report use of micellar TLC [15][16] or even reversed phase thin-layer chromatography (RP-TLC) done on silica plates impregnated with oils or fats [17][18][19][20]. So TLC is still seen as an interesting alternative, having its advantages and disadvantages.…”