series of 1-(6-(2-(2-arylethynyl)phenyl)hexyn-5-yl)piperidin-2-ones 2a-j were synthesized and their antitumor activities were evaluated. Of these compounds, 1-(6-(2-(2-(4-nitrophenyl)ethynyl)phenyl)hexyn-5-yl)piperidin-2-one (2j) showed the highest potency of growth inhibition activity, especially against the RPMI-8226 (0.4 μM) and SR (0.02 μM) cell lines of human leukemia. Compound 2j also induced significant