Synthesis of a natural chalcone and its prenyl analogs--evaluation of tumor cell growth-inhibitory activities, and effects on cell cycle and apoptosis.

Six prenyl (=3-methylbut-2-en-1-yl) chalcones (=1,3-diphenylprop-2-en-1-ones), 2-7, and one natural non-prenylated chalcone, 1, have been synthesized and evaluated for their in vitro growth-inhibitory activity against three human tumor cell lines. A pronounced dose-dependent growth-inhibitory effect was observed for all prenylated derivatives, except for 7. The chalcone possessing one prenyloxy group at C(2'), i.e., 2, was the most active derivative against the three human tumor cell lines (5.9<GI₅₀<7.7 μM). The majority of compounds caused an increase in percentage of apoptotic cells and/or they interfered with cell cycle distribution in the MCF-7 cell line.