Transition metal cations catalyze O/O exchange of catechol motifs with HO.

Catechol motifs are ubiquitous in nature, as part of plant, animal and microbial metabolites, and are known to form complexes with various metal cations. Here, we report for the first time that complexation with transition metal cations, especially Fe(III), results in rapid O/O exchange of the catecholic hydroxyl groups with HO. We discuss the implications of this finding for mechanistic studies using HO and potential relevance for production of O-labeled catechol derivatives.

Modeling the Solubility of Phenolic Acids in Aqueous Media at 37 °C.

In this work, the solubility of vanillic, gallic, syringic, -coumaric, ferulic and caffeic acids was determined at 37 °C under different conditions, namely pure water and two different ionic media, NaCl(aq) and NaClO(aq), at different ionic strengths (i.e., 0.

A Review on Coordination Properties of Al(III) and Fe(III) toward Natural Antioxidant Molecules: Experimental and Theoretical Insights.

This review focuses on the ability of some natural antioxidant molecules (i.e., hydroxycinnamic acids, coumarin-3-carboxylic acid, quercetin, luteolin and curcumin) to form Al(III)- and Fe(III)-complexes with the aim of evaluating the coordination properties from a combined experimental and theoretical point of view.

Sequestering Ability of a Synthetic Chelating Agent towards Copper(II) and Iron(III): A Detailed Theoretical and Experimental Analysis.

In the continuous effort to identify selective chelators towards bioavailable and toxic metal ions, the potential selectivity of a novel N,O chelating ligand, recently synthesized and claimed to be able to bind to Cu(II) ions forming stable complexes while leaving unaltered the level of essential metal ions, was scrutinized using a combined theoretical and experimental approach. A multistep synthetic procedure was used to synthesize the ligand, whose chelating properties along with the stability of the complexes formed binding Cu(II) and, for comparison, Fe(III) ions were evaluated using potentiometric measurements and UV-Vis spectroscopy. DFT analysis allowed to disclose the structural characteristics of the formed complexes.

A rapid method for the quantification of urinary phthalate monoesters: A new strategy for the assessment of the exposure to phthalate ester by solid-phase microextraction with gas chromatography and tandem mass spectrometry.

In the following work, a new method for the analysis of the phthalate monoesters in human urine was reported. Phthalate monoesters are metabolites generated as a result of phthalate exposure. In compliance with the dictates of Green Analytical Chemistry, a rapid and simple protocol was developed and optimized for the quantification of phthalate monoesters (i.