Cytotoxic activities of 6-arylamino-7-halo-5,8-quinolinediones against human tumor cell lines.

6-Arylamino-7-halo-5,8-quinolinediones (4a-4k, 5a-5b) were tested for in vitro cytotoxicity against human solid tumor cell lines such as A 549 (non-small cell lung), SK-OV-3 (ovarian), SK-MEL-2 (melanoma), HCT-15 (colon) and XF 498 (CNS) by SRB assay. The arylamino-7-chloro-5,8-quinolinediones 4 were also evaluated for cyclin-dependent kinase (CDK2 and CDK4) inhibitory effect. Among them, the 5,8-quinolinediones 4a and 5a with 7-(4-fluorophenyl)amino group were found to be potent cytotoxic against HCT 15, SKOV-3 and XF 498, and the compounds 4f and 4i showed inhibitory activities for the CDK4.