Synthesis and biological evaluation of styrylheterocycles analogs of resveratrol as apoptosis-inducing agents

Background: Apoptosis is a route of cell death induced by a highly regulated intracellular program. An increase in apoptotic activity could lead to neurodegenerative pathologies, whereas a decrease in apoptotic activity could lead to uncontrolled cellular proliferation. Objective: The aim of this research was to synthesize ten styrylheterocycle compounds, analogs of resveratrol, having a thiophene ring substituted in position 2- or 3- and a benzene ring with one or two hydroxy and methoxy groups. The compounds were evaluated for their cytotoxicity and apoptotic activity against the U-937 cancer cell line. Method: The experiments were conducted at 1000 µM, 250 µM, 100 µM, and 50 µM in order to measure apoptotic activity (% hypodiploid nuclei). The cytotoxicity was expressed as the concentration of a substance able to inhibit 50% of the metabolic activity in an MTS assay (maCC50), and as the percentage of cellular death (% Death Cell.) at 1000 µM and 100 µM. Results: Changing the phenyl group in a thienyl group occupying the 2- or 3-position almost always leads to an improvement in apoptosis. In addition, whereas the presence of a hydroxy group makes the molecules more cytotoxic than resveratrol, it also improves apoptosis. However, the presence of a methoxy group in the phenyl ring leads to collapse of the cytotoxicity, thereby allowing an increase in the analytical concentrations, and verifying that, at 1000 µM, the compounds 3b and 3c show apoptosis levels of 81% and 72%, respectively. Conclusion: We look forward to synthesizing other heterocyclic molecules to find even more active derivatives endowed with anti-cancer potential.