Oxygenation of Nucleosides by Peroxide Adduct of Binuclear Iron(III) Complex with a μ-Oxo Bridge

Abstract

Abstract The (μ-oxo)(μ-carbonato)diiron(III) complex with H2(tfda) (H2(tfda) = 2-aminomethyl-tetrahydrofuran-N,N-diacetic acid) exhibited high activity for hydroxylation of 2′-deoxygua-nosine in the presence of hydrogen peroxide, giving 8-hydroxydeoxyguanosine, but its hy­ droxylation activity towards other nucleosides such as 2′-deoxyadenosine, adenosine or thym­ idine was found negligible. In the case of the Fe(III)-(ed a) complex (H2(eda) = 2-methoxyethylamine-N,N-diacetic acid), hydroxylation occurred mainly at the sugar site, con­verting 2′-deoxyguanosine to guanosine. Based on the spectroscopic and structural properties of these iron(III) compounds, it seems most likely that an intrinsic active species for hydrox­ylation should be an electrophilic peroxide adduct of the (μ-oxo)diiron(III) core with η1 coordination mode, while the contribution of OH· sides is ruled out.