(E)-3-(3-([1,1′-Biphenyl]-4-yl)-1-phenyl-1H-pyrazol-4-yl)-1-phenylprop-2-en-1-ones inducing reactive oxygen species generation through glutathione depletion

The accumulation of reactive oxygen species (ROS) disrupts reduction–oxidation homeostasis, which can result in damage to cancer cells. To identify the compounds generating ROS, compounds containing Michael acceptors were designed because they are suggested to be critical for ROS elevation via glutathione depletion. Twelve (E)-3-(3-([1,1′-biphenyl]-4-yl)-1-phenyl-1H-pyrazol-4-yl)-1-phenylprop-2-en-1-ones were synthesized and identified using nuclear magnetic resonance spectroscopy and mass spectrometry. Intracellular ROS levels induced by treatment with the compounds were determined using fluorescence microscopy with the oxidant-sensing fluorescent probe 2′,7′-dichlorodihydrofluorescein diacetate. We selected compound 9, which showed the highest activity, and performed further biological experiments, including glutathione depletion and apoptosis assays, using MIA PaCa-2 pancreatic cancer cells. Additionally, the reason why the intracellular ROS level by compound 9 was lower than that of menadione used as a control was explained through in silico docking experiments. Our findings suggest that compound 9 has the potential to act as an anticancer agent by inducing ROS generation through the depletion of intracellular glutathione.