An Approach to Model the Active Site of Peptidglycine‐α‐hydroxylating monooxygenase (PHM)

Abstract

The copper(I) and copper(II) complexes [Cu((TMGet)2NetSEt)]BPh4 (1·BPh4) and [Cu((TMGet)2NetSEt)Cl]Cl (2·Cl) with (TMGet)2NetSEt = ((Me2N)2C=NCH2CH2)2NCH2CH2SEt were synthesized and structurally characterized as a model system for the copper enzyme PHM, a monooxygenase involved in the activation of peptide hormones and neuropeptides. The reaction of the copper(I) complex 1·BPh4 with dioxygen has been studied using low temperature stopped‐flow methods. However, in contrast to PHM no formation of an end‐on copper superoxido complex could be observed. Instead an equilibrium between a bis‐μ‐oxo and a side‐on peroxide complex was detected spectroscopically.

Employing Linear Tridentate Ligands with Pyrazole End Groups in Catalytic Tyrosinase Model Chemistry: Does Hemilability Matter?

“…We speculated that that the five‐ring metallacycles obtained upon coordination of pzma to copper(II) (see above) might eventually be unfavorable for the stabilization of the µ‐η 2 :η 2 peroxo dicopper core. Although examples of µ‐η 2 :η 2 peroxo dicopper complexes supported by NNN ‐type ligands with five‐ring metallacycles exist,, we note that Casella′s L‐66 complex exhibiting six‐ring metallacycles forms a µ‐η 2 :η 2 peroxo intermediate[17b] whereas its L‐55 counterpart exhibiting five‐ring metallacycles does not . To check whether elongation of the methylene to ethylene bridges in the pzea ligands would increase the stability of the side‐on peroxo dicopper complex, we synthesized the tridentate bis(pyrazolylethyl)amine ligands 2a and 2b after a procedure of Blackman et al .…”

Hydroxyl Radical Generation and DNA Nuclease Activity: A Mechanistic Study Based on a Surface‐Immobilized Copper Thioether Clip‐Phen Derivative

“…In addition, as can be ascertained from the inset in Figure , the potential shifts observed at different pH values are consistent with a two‐electron process and are tentatively assigned to the oxidation of a dimeric species of copper(I). In fact, the formation of reactive intermediates containing oxygen species as bridging ligands has been claimed by several groups, particularly those attempting to isolate compounds that mimic the active site of the copper monooxygenase enzymes to understand their Cu I /O 2 reactivity …”

A panel of peralkylated sulfur–guanidine type bases: Novel pro-ligands for use in biomimetic coordination chemistry

“…Thus, molecules containing mixed N/S donor functions should principally be capable to mimic both histidine/methionine or histidine/cysteine coordination situations under properly defined reaction conditions. More recently, we have also shown that even tripodal guanidine-thioether hybrids can act as suitable ligands towards copper(I) and copper(II) resulting in complexes which have been investigated in view of molecular oxygen activation [18].…”