Design, Synthesis, and Apoptosis-Promoting Effect Evaluation of Chalcone Derivatives Containing Aminoguanidine Units

Background: Chalcones are precursors of flavonoids or isoflavonoids, and they are abundant in edible plants. Chalcones constitute an important group of natural and synthetic products with a wide range of pharmacological activities. Objective: To determine the seeds of the anti-tumor agents, we focused on the potential bioactive materials obtained from chalcone derivatives. Methods: Two series of chalcone derivatives containing aminoguanidine or bis-chalone were designed, synthesized, and screened for their cytotoxicity, proliferation inhibition, and apoptosis-promoting activity in vitro against a panel of human tumor cell lines. Results: Among the various compounds studied in this work, 2-((E)-4-((E)-3-oxo-3-(p-tolyl)prop-1-en-1- yl)benzylidene)hydrazine-1-carboximidamide (5f) was the most potent, with IC50 values of 7.17 μM and 3.05 μM antiproliferative activity in vitro against human hepatocarcinoma HepG2 cells and SMMC-7721 cells, respectively. This result showed that the compound possessed a certain degree of selectivity for human hepatocarcinoma cells, especially for SMMC-7721. Then, Annexin V/PI flow cytometry assay was used to investigate different concentrations of compound 5f to demonstrate the ability of compound 5f in inducing apoptosis of SMMC-7721 cells in a concentrationdependent manner. Finally, these results were further verified by Western blot analysis. Conclusion: Based on the collective results, compound 5f may be a promising anti-cancer compound, and may play a significant role in subsequent research.