Quantum modeling of the toxicity of selected Anti-Candida albicans Schiff bases and their Nickel (II) complexes

A set of 28 anti-Candida albicans Schiff bases and their Ni(II) complexes with their experimental median lethal dose (LD50) were selected for 0D, 1D, 2D and 3D quantitative structure activity relationship (QSAR) analysis by means of Density Functional Theory using the B3LYP version and 6-31G* basis set. The computed descriptors were correlated with their experimental LD50. Genetic function approximation (GFA) method and Multi-linear regression analysis (MLR) was used to derive the most statistically significant QSAR model. Among the obtained QSAR models, the most statistically significant one was a tetra parametric linear equation with the squared correlation coefficient R2 value of 0.9464, adjusted squared correlation coefficient R2adj value of 0.9321 and Leave one out (LOO) cross validation coefficient (Q2) value of 0.9010. An external set was used for confirming the predictive power of the model, its R2pred = 0.7621. It is envisaged that the QSAR results identified in this study will offer important structural insight into designing novel less toxic anti-Candida albicans drugs from Schiff base and their nickel (II) complexes.