The effect of structural changes in a polyamine backbone on its DNA-binding properties.

A novel analog of spermine, compound 1, 2, 6 bis(N-3-aminopropylmethanamine)-1-methoxy-4-methylbenzene, has been prepared which shows DNA binding which is altered from spermine in its base pair selectivity. A fluorescence spectroscopic assay is used to compare the complexation properties of compound 1, spermine, spermidine, putrescine, and berenil binding to calf thymus DNA, poly d(AT), and poly d(GC). The results are interpreted in terms of a major groove binding motif and compared with literature values for DNA dissociation constants.