Selected isomeric methylphenols, chlorophenols and nitrophenols have been separated by TLC on silanized silica gel and the pK(a) values of the compounds correlated with R(M), values and with numerical values of the topological indexes: M, (0) chi(v), (1) chi(v), (2) chi(v), W, I-B, A, B-0, B-1, B-2, and B-2(q).The most accurate prediction of the pK(a) values of the phenols investigated was achieved by use of biparametric equations employing R(M) values and the topological indexes M or B-0.

Isomeric disubstituted benzene derivatives have been separated by TLC on silica gel. For prediction of the values of the dipole moments (mu)) of the selected isomers investigated the best correlation was obtained with triparametric equations which combined R(M) values with the topological indexes B-0 and B-1 or with B-0 and B-2. This is the first time topological indexes have been used for prediction of dipole moments and constitutes a new application of thin-layer chromatography. The investigations were semi-quantitative in nature.

Selected isomeric phenol derivatives have been separated by partition TLC. Values of R(M), partition coefficients, log P, toxicological properties, log 1/C-T, and antibacterial activity, log 1/C-A, have been correlated with numerical values of the topological indexes: M, K-0(V), K-1(V), K-2(V), K-3(V), W, I-B, A, B-0, B-1, B-2, B-2(q), B-3, B-3(q), C, D, and K-012. Many correlation equations with high correlation coefficients (r > 0.95) were obtained; these enable prediction of numerical values of R(M), log P, log 1/C-T, log 1/C-A, and the topological indexes for the isomeric phenol derivatives investigated. By suitable transformation of the equations obtained it is possible to obtain new correlation equations enabling calculation of antibacterial activity, log 1/C-A, and numerical values of topological indexes; this further increases the possibility of formulating rules for analytical identification of the compounds. These investigations had semi-quantitative character.

Eleven new visualizing agents in the form of thirteen visualizing systems have been applied to detection of selected fatty vitamins (D-2, D-3, A, E) after their separation on adsorption and partition TLC. It was found that more advantageous visualizing effects for all investigated vitamins were obtained on adsorption TLC compared with partition TLC. In adsorption TLC, for majority of investigated visualizing agents, the best limits of detection for investigated vitamins follow the sequence: vitamine E, vitamine A, vitamine D-2 and D-3.

Selected isomeric methylphenols have been separated bf TLC on silanized silica gel. R(M) and toxicological log 1/C values have been correlated with the hydrophobic constant pi, with pK(a) values, and with numerical values of the topological indexes M, (0) chi(v), (1) chi(v), (2) chi(v), 3 chi(v), W, I-B, A, B-0, B-1, B-2, B-2(q), B-3, B-3(q), C, D, and chi(012). A series of monoparametric equations with high correlation coefficients was obtained; these equations enabled prediction of R(M) and log 1/C values for the methylphenols investigated. Multiparametric equations used for prediction of R(M) and log 1/C values were characterized by smaller values of standard errors than were monoparametric: equations. The best correlation was found for use of the topological indexes (0) chi(v), (1) chi(v), (2) chi(v), A, B-3, B-3(q), C, D, and chi(012). These results testify to the special significance of topological indexes for estimating the physico-chemical and biological properties of selected organic compounds. These investigation had semi-quantitative character.

Phenol and selected isomeric chlorophenols have been separated by TLC on silanized silica gel. Values of R(M), minimum lethal dose log MLD, and toxicity log LC(50) were correlated with energy effect E (related to pi-energy and hydrogen-bonding energy), pK(a) values, and with numerical values of the topological indexes M, (0)k(v), (1)k(v), (2)k(v), (3)k(v), W, A, I-B, B-0, B-1, B-2, B-2(q), B-3 B-3(q), C, D, and chi(012). Many correlation equations with high correlation coefficients (r > 0.95) have enabled prediction of R(M), log MLD, and log LC(50) values. The greatest number of significant correlation equations was obtained for the topological indexes (2)k(v), W, A, B-2, B-2(q), B-3(q), D, and k(012). By suitable transformation of some of the equations obtained it has been possible to derive nerv correlation equations enabling calculation of minimum lethal dose log MLD and toxicological properties log LC(50). This has led to specific principles for analytical identification of the compounds and prediction of their biological properties. These investigations had semi - quantitative characters.

Selected benzoic acid derivatives have been separated by thin layer adsorption chromatography. R(M) values and biological activity (toxicity towards mosquito larvae) log 1/C, were correlated with numerical values of topological indices (I(t)), Hammett constants, sigma, hydrophobic constants, pi, and partition coefficients, log P. Many correlation equations with high correlation coefficients (r > 0.99) were obtained and these enabled prediction of R(M) values, log 1/C values, and the numerical values of topological indices for the benzoic acid derivatives investigated.On the basis of suitable transformation of the equations obtained it was possible to obtain new correlation equations which enabled the calculation of numerical values of topological indices which could be used to formulate rules for analytical identification of the compounds studied.

Bromothymol blue, thymol blue, phenol red, helasol green, bromocresol green, brilliant cresyl blue, bromophenol blue, neutral red, aniline blue, alkaline blue, brilliant green, sudan I, sudan II, sudan III, and sudan IV have been investigated as new visualizing agents for the detection of cholesterol in adsorption, argentation, and partition TLC. It was found that these visualizing agents are of limited application for detection of cholesterol. The most advantageous conditions were obtained with use of aluminum oxide as adsorbent. Quantitative determination of cholesterol on silica gel and neutral aluminum oxide after detection with bromophenol blue and aniline blue has been possible by use of four regression equations.

Stereoisomeric menthols and thujols have been separated by thin layer adsorption chromatography. A new stereoisomeric topological index has been proposed (I(STI)) which enables distinction between stereoisomers with hydroxyl groups in axial and equatorial positions.

Selected aromatic alcohols have been separated by TLC and correlations sought between R(M), the partition coefficient, log P, calculated using Rekker fragmental constants, and the numerical values of the topological indexes M, 0X(v), 1X(v), 2X(v), 3X(v), W, I(B), A, 0B, 1B, 2B, B-2(q), 3B, B-3(q), C, D, and X012. Many correlation coefficients (r > 0.99) were indicative of high correlation, enabling prediction of R(M), log P, and numerical values of topological indexes for the alcohols investigated. By suitable transformation of the equations obtained it was possible to derive new correlation equations enabling the calculation of numerical values of topological indexes which could be used in the formulation of rules for analytical identification of the compounds studied.

Selected hydroxy acids and amino acids have been separated into their enantiomers by thin layer chromatography on a chiral stationary phase. A new optical topological index (I(opt)) is proposed which enables distinction between isomers of D and L configuration.