Secondary sphere interactions modulate peroxynitrite scavenging by the E2 domain of amyloid precursor protein.

Peroxynitrite (ONOO) is a highly reactive nitrogen species that can cause significant damage to proteins, lipids, and DNA. Various enzymes, including metalloenzymes, play crucial roles in reducing ONOO concentrations to protect cellular components. While the interaction of ONOO with heme proteins is well known, the reduction by Cu-containing proteins is less studied.

Enantioconvergent Copper-Catalysed Difluoromethylation of Alkyl Halides.

Stereochemical-controlled hydrogen bond donors play essential roles in the pharmaceutical industry. Consequently, organic molecules that bear difluoromethyl (CF2H) groups at chiral centers are emerging as pivotal components in pharmaceuticals due to their distinct hydrogenbonding property. However, a general approach for introducing CF2H groups in an enantioselective manner remained elusive.

Catalytically Relevant Organocopper(III) Complexes Formed through Aryl-Radical-Enabled Oxidative Addition.

Stepwise oxidative addition of copper(I) complexes to form copper(III) species via single electron transfer (SET) events has been widely proposed in copper catalysis. However, direct observation and detailed investigation of these fundamental steps remain elusive owing largely to the typically slow oxidative addition rate of copper(I) complexes and the instability of the copper(III) species. We report herein a novel aryl-radical-enabled stepwise oxidative addition pathway that allows for the formation of well-defined alkyl-Cu species from Cu complexes.

Enabling Valence Delocalization in Iron(III) Macrocyclic Complexes through Ring Unsaturation.

The complexes [Fe(HMC)(CDMA)]CFSO ([]OTf) and [Fe(HMTI)(CY)]CFSO ([-]OTf) have been prepared and thoroughly characterized (HMC = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane; HMTI = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene; Y = Fc (ferrocenyl, []OTf), 4-(,-dimethyl)anilino (DMA, []OTf), or 4-(,-bis(4-methoxyphenyl)anilino (TPA, []OTf); OTf = CFSO)). Vibrational and electronic absorption spectroelectrochemical analyses following one-electron oxidation of the ethynyl substituent Y revealed evidence of strong coupling in the resultant mixed valent species for all HMTI-based complexes. However, the analogous mixed valent ion based on []OTf appeared to be more localized.

Revisit the E2 Domain of Amyloid Precursor Protein: Ferroxidase, Superoxide and Peroxynitrite Scavenging Activities.

Amyloid precursor protein (APP) is the biological precursor of β-amyloids, a known histopathological hallmark associated with Alzheimer's disease (AD). The function of APP is of great interest yet remains elusive. One of the extracellular domains of APP, the E2 domain, has been proposed to possess ferroxidase activity and affect neuronal iron homeostasis.

Actinide-Oxygen Multiple Bonds from Air: Synthesis and Characterization of a Thorium Oxo Supported by Redox-Active Ligands.

The first non-uranyl, f-element oxo complex synthesized from dioxygen in dry air is presented in this work. The synthesis was accomplished by treating the redox-active thorium amidophenolate complex, [Th(ap)][K(15--5)] (), with dioxygen in dry air, forming a rare terminal thorium oxo, [O═Th(isq)(ap)][K(15--5)] (). Compound was regenerated by treating with potassium graphite.