6. Polymeric Ferrocene Conjugates as Antiproliferative Agents

Summary

Ferrocene, di-(0⁵-cyclopentadienyl)iron(II), a key representative of the class of organometallic compounds known as metallocenes, has found numerous divergent applications in science and technology. The compound owes this multivaried behavior pattern largely to its unusual electronic structure and resultant oxidation-reduction properties. Attracted by the challenges offered in the realm of the biosciences, a major stream of investigative activities, as shown in Section II of this chapter, has flowed into biochemistry, where evidence of significant interaction of the nonpolymeric ferrocene–ferricenium system with the biological environment has been provided. In more recent years, the biomedical target presented by the proliferative cancer cell has emerged as a particularly rewarding topic in metallocene research. We have seen that strong antiproliferative, i.e. cell growth-inhibiting action, can be observed as cultured cancer cells are exposed in vitro to selected water-soluble ferrocene derivatives, especially those comprising the metallocene in its Fe(III) (ferricenium) state. We have also seen that excellent antineoplastic activity is evident even in certain in vivo systems.