Functional models for catechol 1,2-dioxygenase. Structure, reactivity, and mechanism

Iron(III)- and copper(II) complexes of an asymmetric, pentadentate salen-like ligand bearing a pendant carboxylate group

“…Metal complexes of salen (N,N 0 -ethylenebis(salicylideneimine)) and its derivatives have been extensively studied as model complexes of the active sites of mononuclear dioxygen activating enzymes, such as some irondependent dioxygenases [1][2][3] or galactose oxidase [4][5][6]. Besides, a number of complexes formed with salen-like ligands were used as catalysts for diverse organic redox reactions [7][8][9].…”

Heterobimetallic gadolinium(III)–iron(III) complex of DTPA-bis(3-hydroxytyramide)

“…An immediate colour change from yellow to dark violet was a strong indication of formation of an iron catecholate complex [11]. This is illustrated in Fig.…”

“…DTPA was obtained from Koch Light Laboratories. The DTPA-bis(anhydride) and [Fe(NTA)(H 2 O) 2 ], where NTA is nitrilotriacetic acid, were synthesised according to previously reported procedures [10,11]. 1 H NMR spectra were run on a Bruker Avance 300, operating at 300 MHz.…”

Iron‐Substituted Polyoxotungstates as Inorganic Synzymes: Evidence for a Biomimetic Pathway in the Catalytic Oxygenation of Catechols

“…Therefore, on the basis of earlier arguments, we associate the increased cleavage specificity to an increase of the Fe Lewis acidity within the Fe 4 X 2 W 18 series, by enhancing the semiquinone character of the reactive intermediate and, in a second step, by facilitating the decomposition of the peroxy intermediate to the cleavage products (Scheme 1), in agreement with the enzymatic paradigm. [34] The reactivity correlation traced within the Fe 4 X 2 W 18 Krebs-type family provides convincing evidence of the POM involvement, and at the same time, it establishes a fundamental reference point to bridge the gap with classical organic ligands. In this respect, the combined spectroscopic and reactivity evidence is instrumental for a descriptoraided design of novel dioxygenase functional models, built from totally inorganic POM-based ligands.…”