Chiral Pyrazolo[4,3-e][1,2,4]triazine Sulfonamides—Their Biological Activity, Lipophilicity, Protein Affinity, and Metabolic Transformations

Referring to our previous laboratory results related to the tyrosinase and urease inhibition by pyrazolo[4,3-e][1,2,4]triazine sulfonamides, we examined here in silico the mechanism of action at the molecular level of the investigated pyrazolotriazine sulfonamides by the molecular docking method. The studied compounds being evaluated for their cytotoxic effect against cancer cell lines (MCF-7, K-562) and for recombinant Abl and CDK2/E kinase inhibitory potency turned out to be inactive in these tests. The pyrazolotriazines were also investigated with respect to their lipophilicity and plasma protein binding using HPLC chromatography in isocratic conditions. The observed small affinity for plasma proteins could be advantageous in the potential in vivo studies. Moreover, the compounds were sensitive to metabolic transformations with phase I enzymes, which led to the hydroxylation and dealkylation products, whereas phase II transformations did not occur.