Synthesis of Polymethoxyflavonoids from Hesperidin and Naringin and their Antiproliferative Activity

A series of polymethoxyflavonoids were synthesized via cleavage of the glycosidic bond, dehydrogenation, selective methylation, bromination, nucleophilic aromatic substitution, O -prenylation, Claisen–Schmidt aldol condensation, cyclization, and oxidation from very abundant and inexpensive natural flavonoids hesperidin and naringin. The in vitro antiproliferative activity of the synthesized compounds was evaluated against a panel of four human cancer cell lines (Aspc-1, HCT-116, HepG-2, and SUN-5) by the CellTiter-Glo assay. The results showed that some of synthesized compounds exhibited moderate to high antiproliferative activity. Among them, (2 E )-1-(2-hydroxy-3,4,5,6-tetramethoxyphenyl)-3-(7-methoxy-1,3-benzodioxol-5-yl)prop-2-en-1-one was revealed to be the most active with IC50 values ranging from 10.35 to 13.89 μM against all four cancer cell lines, the IC50 value (10.35 μM) being below positive control cisplatin (12.36 μM) against HepG-2 cells.