1H and 13C NMR measurements were carried out to explore anticipated correlations between chemical shifts versus thiolate basicities redox potentials of cysteamine, homocysteine, penicillamine, their homodisulfides. All analyzed statistically evaluated. The closest correlation was observed for the αCH nuclei concerning data. Since neither site-specific nor can be directly measured by any means i...

Chromogenic receptors 2 and 3 undergo distinct colour changes from magenta to blue on gradual addition of Cu(II) and can be used as colorimetric probes for spectrophotometric and visual analysis of Cu(II) in the presence of biological metal ions Na(I), K(I), Mg(II), Ca(II), Fe(II), Zn(II) etc. in aqueous solution (methanol-water 1 : 1 v/v). On addition of Cu(II), both 2 and 3 exhibit a bathochr...

Protonation of a free-base meso-pyrimidinyl-substituted AB(2)-corrole (H(3)AB(2)) in ethanol solution by stepwise addition of sulfuric acid has been studied in the temperature range from 293 to 333 K. The formation rate of protonated species was found to depend profoundly on the temperature at which the titration was undertaken. Two steps in the titration curve were identified at temperatures a...

New potentiometric experiments have been performed in NaCl and in (CH3)4NCl media, to determine the protonation constants, the protonation enthalpy changes and the solubility of six natural α-amino acids, namely Glycine (Gly), Alanine (Ala), Valine (Val), Leucine (Leu), Serine (Ser) and Phenylalanine (Phe). The aim of the work is the rationalization of the protonation thermodynamics (log [Formu...

Equilibrium constants of Cadmium Oxide (CdO) nanoparticles complexes in human cancer cells with DNA/RNA ligands have been studied with biospectroscopic methods such as 1HNMR, 13CNMR, 31PNMR, Attenuated Total Reflectance Fourier Transform Infrared (ATR–FTIR) and FT–Raman spectroscopies in cosolvent systems at 10, 20, 30°C ± 0.5 and 1 mol.dm–3 ionic strength, was maintained using Sodium Chloride ...

Three new Schiff bases derived from the condensation reaction of thiophene-2-carbaldehyde and DL-alanine, DL-valine and DL-phenylalanine have been synthesized and their Co(II), Ni(II) and Cu(II) complexes have been prepared. The Schiff bases and the complexes have been characterized by their analytical and spectral data. The protonation constants of the Schiff bases and stability constants of t...

Following previous studies with a DOTA-like bifunctional chelator (H(3)L1) containing an ethylenic linker between the macrocycle backbone and a quinazoline pharmacophore, we synthesized and fully characterized a congener macrocyclic ligand (H(3)L2) having a longer, five-carbon spacer for the linkage of the quinazoline moiety. Both H(3)L1 and H(3)L2 were used to prepare indium(III) complexes aim...

The formation constants of the species formed in the systems fr + glycine + dioxovanadium(V) + and H+ + glycine have been determined in aqueous solutions of methanol at 25 °C and constant ionicstrength, using spectrophotometric and potentiometric techniques. It was shown thatdioxovanadium(V) forms two mononuclear 1 : land 1:2 complexes with glycine. The formationconstants in various media were ...