Effects of compounds 5d (b), 5i (c), 5k (d), 5l (e), 5m (f), and 5n (g) on DNA content/cell following treatment of K562 cells for 24 h. The cells were cultured without compound (Control, a) or with compound used at the concentration leading to 50% cell growth inhibition after 24 h of treatment. Cell cycle distribution was analyzed by the standard propidium iodide procedure as described in Section 5. Sub-G0-G1 (A), G0-G1, S, and G2-M cells are indicated in the control panel.