Competitive coordination between lead and oligoelements with respect to some therapeutic heavy‐metal chelators

Abstract

The if EDTA is concerned. The first two chelators thus appear as better entities than EDTA to be used in chelation therapy, where in vivo selective complexation is essential. Moreover, the comparison of the bonding characteristics of Pb 2ϩ with those of the other cations allows deriving three features to be taken into account in designing new chelators expecting to have an increased selectivity toward this cation.

Application of the topological analysis of the electronic localization function to archetypical [Pb(II)Ln]p complexes: The bonding of Pb2+ revisited

“…These are, for some complementary testing purposes (see latter) the small‐core SDD PPs (60 electrons pseudized for neutral Pb),34 and, for the final results reported, the large‐core relativistic SDD PPs by Dolg and coworkers35 (78 electrons pseudized for neutral Pb) coupled to a (4s4p1d)/[2s2p1d] contraction to describe the valence electrons. These functional, basis set and PPs have been successfully used in our previous works devoted to Pb 2+ or to other heavy cations and have proven to reproduce four‐component computations 12, 17–22, 31, 32, 36…”

“…The key role of the external valence lone‐pair of Pb 2+ has however been experimentally and theoretically evidenced,6, 7, 12–22 and has already been used in elaborating dedicated sequestering ligands 23, 24. But rationales still remain required, not only for an intrinsic comprehension of the Pb(II) chemistry, but also to help in designing chelators usable in vivo or to develop reliable force fields, for instance.…”

Penicillamine-modified sensor for the voltammetric determination of Cd(II) and Pb(II) ions in natural samples

“…It is well-known the affinity of some chelators to different cations as Cu 2+ , Fe 2+ , Ca 2+ , Zn 2+ , and Pb 2+ [11]. Particularly, D-penicillamine (Pen -Cuprimine, Depen), that has long been used as the drug of choice in the treatment of Wilson's disease or hepatolenticular degeneration, is a potential and effective chelator for some transition metals [12][13][14].…”

Enforcing hemidirectionality in Pb(II) complexes: The importance of anionic ligands

“…The aim of this theoretical work is to focus on some characteristics that a chelator must have to be selective. Such an achievement requires a better understanding of the Pb 2+ valence lone pair behavior in various environments since it has been shown in several quantum chemistry studies to be the driving entity governing the chemical physics of lead at a molecular level [10][11][12][13][14][15][16][17]. Indeed, it is well-known that this lone pair can be hemidirected (extending into one hemisphere and being stereochemically active), holodirected (surrounding the Pb 2+ cation and being stereochemically inactive), or even bisdirected (stereochemically active but split into two opposite lobes) [13], as depicted in Figure 1.…”

“…We chose Cl À /HCl in order to have a representative electronegative ligand and SH À /SH 2 as a model of a softer ligand. Following our previous studies, we have resorted to the topological analysis of the Electron Localization Function (ELF) [18,19] to characterize the directionality of the valence lone pair [10][11][12][13][14][15][16][17].…”