Abstract
4-Amino-2H-benzo[h]chromen-2-one (ABO) analogs were designed, synthesized, and evaluated for cytotoxic activity. Among all 4-substituted ABO analogs, cyclohexyl (12), N-methoxy-N-methylacetamide (14), and various aromatic derivatives (15-25 and 27) exhibited promising cell growth inhibitory activity with ED(50) values of 0.01-5.8 microM against all tested tumor cell lines. The 4'-methoxyphenyl derivative (18) and 3'-methylphenyl derivative (24) showed the most potent antitumor activity against a broad range of cancer cell lines with ED(50) values of 0.01-76 microM. Preliminary SAR results indicated that substitutions on nitrogen are critical to the antitumor potency.