Crystal structures of acridines complexed with nucleic acids.

Acridines have been used as chemotherapeutic agents against bacteria, protozoa and fungi, and they now find important use as anticancer drugs. There is a paucity of crystal structures of acridine-DNA complexes above the dinucleotide level, but recent structures of acridinecarboxamide topoisomerase II poisons complexed to hexanucleotides have allowed a molecular rationalization of their structure-activity relationships for cytotoxicity and for their kinetics of DNA binding.