Design, synthesis, cytotoxicity, HuTopoIIα inhibitory activity and molecular docking studies of pyrazole derivatives as potential anticancer agents

Abstract

In an attempt to find potential anticancer agents, a series of novel ethyl 4-(3-(aryl)-1-phenyl-1H-pyrazol-4-yl)-2-oxo-6-(pyridin-3-yl)cyclohex-3-enecarboxylates 5a-i and 5-(3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)-3-(pyridin-3-yl)-4,5-dihydropyrazole-1-carbothioamides 6a-i were designed, synthesized and evaluated for their topoisomerase IIα inhibitory activity and in vitro cytotoxicity against a panel of cancerous cell lines (MCF-7, NCI-H460, HeLa) and a normal cell line (HEK-293T). Molecular docking studies of all the synthesized compounds into the binding site of topoisomerase IIα protein (PDB ID: 1ZXM) were performed to gain a comprehensive understanding into plausible binding modes. These compounds were also screened for in silico drug-likeliness properties on the basis of the absorption, distribution, metabolism and excretion (ADME) prediction. Among all the synthesized compounds, analogue 5d showed superior cytotoxicity with an IC₅₀ value of 7.01±0.60μM for HeLa, 8.55±0.35μM for NCI-H460 and 14.31±0.90 for MCF-7 cancer cell lines. Further, compound 5d showed 70.82% inhibition of topoisomerase IIα at a concentration of 100μM with maximum docking score of -8.24. Results of ADME prediction revealed that most of these compounds showed in silico drug-likeliness properties within the ideal range.

Keywords: Claisen-Schmidt condensation; Cytotoxicity; Docking; Michael addition; Pyrazole; Topoisomerase.