Quantitative structure-retention relationship of new N-substituted 2-alkylidene-4-oxothiazolidines

A quantitative structure-retention relationship (QSRR) was built to investigate the relationship between the structural descriptors of 23 newly synthesized N-substituted 2-alkylidene-4-oxothiazolidines and their chromatographic retention. Retention was investigated by means of the reversed-phase thin-layer chromatography (RP-TLC) on the C(18) and CN stationary phases, using methanol, acetonitrile, and tetrahydrofuran as organic modifiers. Full geometry optimization based on the Austin Model 1 (AM1) semi-empirical molecular orbital method was carried out and a set of physicochemical molecular descriptors was calculated from the optimized structures. QSRR was built by means of multiple linear regression (MLR) and partial least squares regression (PLS). The best MLR and PLS models were chosen, on the basis of comparison of the statistical parameters (squared correlation coefficient (R(2)), cross-validated coefficient (R(cv)(2)), and Fischer significance value (F) were used for MLR and the square of the multiple correlation coefficients for the calibration objects (R(2)Y (cum)) and the square of the multiple correlation coefficients for the cross-validation segments (Q(2)Y (cum)) were used for PLS models). Statistically significant and physically meaningful QSRR provided better insight on understanding the retention behavior of the new series of compounds. Lipohilicity (expressed as log P) was included in all MLR and PLS models.