Some benzoxazoles and benzimidazoles as DNA topoisomerase I and II inhibitors


Oksuzoglu E., Tekiner-Gulbas B., Alper S., Temiz-Arpaci O., Ertan T., Yildiz I., ...Daha Fazla

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY, cilt.23, sa.1, ss.37-42, 2008 (SCI-Expanded) identifier identifier identifier

Özet

Some novel fused heterocyclic compounds of 2, 5-disubstituted-benzoxazole and benzimidazole derivatives, which were previously synthesized by our group, were investigated for their inhibitory activity on both eukaryotic DNA topoisomerase I and II in a cell free system. 2-Phenoxymethylbenzimidazole (17), 5-amino-2-(p-fluorophenyl)benzoxazole (3), 5-amino-2-(p-bromophenyl)benzoxazole (5), 5-nitro-2-phenoxymethyl-benzimidazole (18), 2-(p-chlorobenzyl)benzoxazole (10) and 5-amino-2-phenylbenzoxazole (2) were found to be more potent as eukaryotic DNA topoisomerase I poisons than the reference drug camptothecin having IC50 values of 14.1, 132.3, 134.1, 248, 443.5, and 495M, respectively. 5-Chloro-2-(p-methylphenyl)benzoxazole (4), 2-(p-nitrobenzyl)benzoxazole (6) and 5-nitro-2-(p-nitrobenzyl)benzoxazole (8) exhibited significant activity as eukaryotic DNA topoisomerase II inhibitors, having IC50 values of 22.3, 17.4, 91.41M, respectively, showing higher potency than the reference drug etoposide.