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Hydrophobicity of ingredients is important for designing food, pharmaceuticals, and cosmetics. Here, we evaluated the hydrophobicity of fatty acids and showed the effect of the alkyl length and the unsaturation degree using reversed-phase thin layer chromatography (RP-TLC). A linear relation was obtained between the methanol concentration in a mobile phase and the Rm value. The linear regression analysis was achieved and the hydrophobicity value Rmw was obtained using the robust regression (MMestimator). The hydrophobicity of fatty acids depends on the structure of alkyl chain as follows: a longer alkyl chain in fatty acid increased the hydrophobicity. Additionally, the hydrophobicity increased as the number of unsaturated parts increased. Fatty acid with branched structures were less hydrophobic than that with straight chained structures. [ABSTRACT FROM AUTHOR]

Lipophilicity plays a crucial role in determining the hepato-selectivity and hence, the biological activity and the associated side effects of statins. Herein, the employment of RP-TLC for estimation of lipophilicity of six statins namely; atorvastatin, simvastatin, pravastatin, lovastatin, rosuvastatin and fluvastatin is examined. A very good correlation between the chromatographically-determined retention parameters (relative lipophilicity (R M0 ) or lipophilic parameter (C 0 )) and both experimental and computed log P values were obtained. However, the results indicate that the type of organic modifier in the mobile phase system (methanol, acetonitrile and acetone) has a small influence on R M0 or C 0 values. Higher values of R M0 or C 0 are ascribed to lipophilic statins and lower values of R M0 or C 0 are attributed to hydrophilic ones. Therefore, R M0 or C 0 could be effectively used as simple practical predictors of extra-hepatic distributions of statins and thus their expected side effects. Furthermore, three QSPR (quantitative structure-property relationship) models were constructed to describe the relationship between R M0 with log P and log D of the statins under investigation. These models can be very useful to predict the lipophilicity of other members of statin drugs and might be expanded to newly synthesized compounds with the same structural features. [ABSTRACT FROM AUTHOR]

Abstract: Reversed-phase thin-layer chromatographic (RP TLC) retention coefficients for a newly designed series of N-phenyl-3-methyl succinimide derivatives, of a rationally expected anticonvusant activity, were determined as parameters of their lipophilicity. Basic pharmacokinetic descriptors of the agents were calculated in silico with the use of the established medicinal chemistry/drug design software. Highly significant, predictive relationships were found between the chromatographic retention constants and the bioactivity descriptors, which are assumed to account for drug absorption, distribution, elimination and toxicity (ADMETox) in humans. Among the agents investigated, the compounds with halogen substituent (Compounds nos. 9–13 in Fig. 1), were identified as the best drug candidates, because of their predicted proper pharmacokinetics, and have been selected for further research and development studies on new antiepileptic drugs. At the same time, among the congeners studied these can be indicated, which should not be rationally subjected to bioactivity tests. [Copyright &y& Elsevier]

• Assessment of selected β-blockers lipophilicity with RP-TLC. • QSRAR model for predicting the protein binding was proposed. • Study of RP-TLC molecular mechanism using QSRR approach. Chromatographic properties of sixteen β-blockers were studied using planar chromatography. The aim of presented study was to investigate influence of different organic solvents (acetonitrile, methanol, dioxin and tetrahydrofurane) on β-blockers' retention on C 18 bonded silica gel stationary phase. Group of sixteen, diverse in terms of structure, beta blockers was used as a model set. The main goal of this study was to compare chromatographically estimated lipophilicity parameters with values obtained with the use of computational methods. Furthermore, in order to understand molecular mechanisms of retention better, quantitative structure-retention relationships (QSRR) analysis was performed. The next step was focused on application of chromatographically obtained lipophilicity parameters for prediction of protein binding (PB), based on quantitative retention–activity relationships (QRAR) approach. The obtained results showed that reversed-phase thin layer chromatography (RP-TLC), especially with tetrafydrofurane used as an organic modifier of mobile phase, is a useful tool for lipophilicity estimation, as well as for prediction of β-blockers' biological properties. The QRAR model included C 0 parameters for tetrahydrofuran-water as a mobile phase, as well as maximal projection area, and can be easily applied for prediction of systematically synthesized β-blockers structures' PB. [ABSTRACT FROM AUTHOR]

Hydrophobicity of ingredients is important for designing food, pharmaceuticals, and cosmetics. Here, we evaluated the hydrophobicity of fatty acids and showed the effect of the alkyl length and the unsaturation degree using reversed-phase thin layer chromatography (RP-TLC). A linear relation was obtained between the methanol concentration in a mobile phase and the R m value. The linear regression analysis was achieved and the hydrophobicity value R mw was obtained using the robust regression (MM-estimator). The hydrophobicity of fatty acids depends on the structure of alkyl chain as follows: a longer alkyl chain in fatty acid increased the hydrophobicity. Additionally, the hydrophobicity increased as the number of unsaturated parts increased. Fatty acid with branched structures were less hydrophobic than that with straight chained structures.