Virtual toxicity of N3, N5-diphenyl-1,4-dihydropyridine-3,5-dicarbohydrazides [2A-2D’] and 2,6-dimethyl-1,4-dihydropyridine-3,5-yl-bis[carbonyl-2-(phenyl)]pyrazolidine-3,5-diones] [3A-3D’] were extensively studied. Computational toxicology and mutagenicity profiles of these compounds were generated by using TOPKAT 6.1 (Toxicity Prediction Komputer Assisted Technology version 6.1). The molecular structure of the query compound was given as a SMILES string and a desired TOPKAT predictor was selected. TOPKAT automatically conducts a unique 2-stage analysis of the query compound. Various models were assessed and obtained results were thoroughly discussed