Competitive fluorescence polarization study of the binding of 1,4-dihydroxy-5,8-bis[(2-[(2-hydroxyethyl) amino] ethyl]amino] 9-10-anthracenedione to DNA.

The title compound is now undergoing Phase I clinical trials as an experimental antitumor agent. Fluorescent polarization was used to determine the extent of inhibition of the binding of acridine orange to DNA. Displacement of 50% of the acridine orange was achieved by 0.21 microM of the title compound, 0.32 microM daunorubicin, 0.41 microM doxorubicin, 0.61 microM dactinomycin, and 7.8 microM cis-platinum. Binding inhibition was essentially equivalent with natural DNAs (calf thymus and Micrococcus luteus) and synthetic polymers [poly d(A):d(T) and poly d(G):d(C)] of widely differing adenine plus thymidine content.