A series of halogenated flavanones were synthesized from 2-hydroxychalcones and tested for their cytotoxicity against a panel of human cancer cell lines. Among the synthesized compounds, 3′, 7-dichloroflavanone (2d) showed the highest activity against MCF-7, LNCaP, PC3, Hep-G2, KB and SK-N-MC cells. However, 3′, 6-dichloroflavanone (2g) with IC50 value of 2.9±0.9 μM was the most potent compound against MDA-MB-231 cells, ...