Antiproliferative agents ferrocene conjugates

Table 1 lists the E° values, determined by cyclovoltammetry in aqueous ethanol for both the free and the polymer-bound acids, and the same trend toward lowest potential for the 4-ferrocenylbutanoic acid and its conjugate is apparent in both columns. Congruent with our working hypothesis (see Section II) that ferrocene exerts its antiproliferative activity as the oxidized, namely, cationic species, 4-ferrocenylbutanoic acid should thus be the preferred vehicle for the introduction of the metallocene into a polymeric structure, and this derivative, indeed, has become the ferrocenylation agent of choice in subsequent investigations. 

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