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Indeksy topologiczne i ich znaczenie w badaniach chromatograficznych. Cz. 2

Pyka A.

Wiadomości Chemiczne

1998

[Z] 52, 9-10

727--754

The prediction of physicochemical and toxicological properties of organic compounds with selected topological indices have been reviewed in monographs and in dedicated articles The first topological indices used to the prediction of selected physicochemical properties (boiling point, heat of formation, heat of vaporization, molar volume, molar refraction) were: Wiener index, polarity number and Platt's index. The Wiener index has been continuously modified In recent years topological indices have come prominently to the fore on several different fronts. The prime reason for wide publicity accorded to these indices has been the remarkable ability to correlate and predict the properties of a vast range of molecular species. Topological indices based on the adjacency matrix, on the distance matrix and on information theory were applicable to the calculation of many physicochemical properties and to the evaluation of biological and toxicological properties of organic compounds. The procedure for calculating the topological indices is illustrated in this work by the calculation of the topological indices based on the adjacency matrix (the Gutman index M1), ; the Randić connectivity indices (0X, 1X, 2X, 0Xv, 1Xv, 2Xv); on the distance matrix (the Wiener index W); the Pyka indices (A, 0B, 1B, 2B); the Balaban index (IB); the Schultz Molecular Topological Index (MTI) for pentamethylenediamine. It should be noted that none of these topological indices yet described differentiates between d and l isomers. The procedure for calculating the optical topological index (Iopt) for d and l isomers is illustrated in this work by the calculation of Iopt for d- and l-alanine. Applications of these topological indices for the correlation analysis are discussed. The TLC, the HPLC and the GC retention parameters of different organic compounds were calculated using equations with the topological indices. As examples, selected correlation equations for calculation retention parameters in TLC, in HPLC, and in GC were shown in this work Definitions of the three-dimensional Wiener number 3W and the mean square distance topological indices of the s-th order D(x) were presented.