Synthesis, interaction with double-helical DNA and biological activity of the water soluble complex cis-dichloro-1,2-propylenediamine-N,N,N',N'-tetraacetato ruthenium (III) (RAP).

The effects exerted by the new complex cis-dichloro-1,2-propylenediaminetetraacetato ruthenium (III), H[RuCl(2)(PDTA-H(2))] [1, RAP], on DNA and cultured tumor cells (ovarian carcinoma TG cell line) were studied. The comparative study of circular dichroism (CD) spectra obtained from DNA and RAP-DNA system evidences the interaction of the complex with DNA. Compound 1 also interacted with tumor TG cells to slow their proliferation rate. BrdU incorporation was enhanced in cells treated with compound 1, as evidenced by a single-cell electrophoresis method (comet assay), in accordance with RAP-induced DNA damage. DNA migration of compound 1-treated cells was similar to that induced by noxious agents other than cross-linking chemicals. The stability of [RuCl(2)(PDTA-H(2))]-DNA binding is suggested by the high degree of damage that persisted after removal of compound 1 from the culture medium.