A chemometric study of megazol derivatives with activity against Trypanosoma equiperdum.

The AM1 semiempirical method was employed to study megazol and 13 of its analogues where their activity against Trypanosoma equiperdum was obtained from in vitro tests. Several molecular properties (descriptors or variables) were calculated for the 14 compounds studied to be correlated with the biological activity. For a practical analysis of large data sets, it is necessary to reduce the dimensionality and select the most relevant descriptors related to the biological activity under study. For this purpose, the following chemometric methods were employed: principal component analysis (PCA), hierarchical cluster analysis (HCA), K-nearest neighbour (KNN), stepwise discriminant analysis (SDA) and soft independent modelling of class analogy (SIMCA). These methods showed that the descriptors molecular electronic energy (Eelet), charge on the first nitrogen at substituent 2 (qN), volume of substituent at C5 position (V-S5), dihedral angle (D3) and bond length between atom C4 and its substituents (L4) are responsible for the separation between active and inactive compounds against T. equiperdum.