In-vitro metabolic profiling study of potential topoisomerase inhibitors 'pyrazolines' in RLMs by mass spectrometry.

Taking into consideration of the cytotoxicity and topo-IIα inhibitory activity of pyrazoline derivatives (1-3) against HCT15 cells, and known topo-IIα inhibitor, etoposide, respectively, the compounds were biotransformed in rat liver microsomes. LC-MS/MS and MALDI mass spectrometric techniques has been used for analysis. All three compounds were biotransformed into demethylated metabolites. Among three compounds, compounds 1 and 2 were biotransformed into mono-hydroxylated metabolites and compound 3 biotransformed into reduced and epoxidized metabolites. Reduced and reduced along with demethylation metabolites were identified from MALDI Orbitrap spectrometric analysis. Without NADPH or microsomes no compounds (1-3) were generated metabolites, it shows CYP450 enzymes involvement in the presence of NADPH in the metabolisms.