Complexing Properties of Pyridine-4-methylene Derivatives: Diethyl(pyridine-4-ylmethyl)phosphate, 4-Pyridylmethylphosphonic Acid and 4-Hydroxymethylpyridine with Cu(II) in Aqueous Solution

Vanadium: History, chemistry, interactions with α-amino acids and potential therapeutic applications

“…In previous sections, we have described the importance of vanadium at industrial level, the chemical speciation of binary and ternary complexes with amino acids and very briefly their importance at the biological level. The studies of chemical speciation in aqueous solution are fundamental to know the nature, abundance and stability of the different species in solution, because they represent an essential requirement to evaluate the biological activity of promising therapeutic targets [121][122][123][124][125][126]. In this section we will discuss the applications of vanadium compounds, especially vanadium complexes with (non)essential amino acids, in pharmacology and medical therapeutics, as well as their importance in bioinorganic chemistry.…”

The complexing properties of oxalodihydrazide, acethydrazide and formic hydrazide with Cu(II) in aqueous solution

“…The concentration formation constants were calculated by the Hyperquad 2008 fitting procedure according to the [25] only for solutions of ionic strength I = 0.1 mol L À1 . The equilibrium model contains the ionic product of water pK w = 13.77 [26] and the formation constants of the aqua-hydroxo complexes of copper(II): [Cu(OH)] + , log 10 b 10À1 = À7.22; Cu(OH) 2 , log 10 b 10À2 = À13.36 [27]. Goodness of fit was checked by the objective function U = R i=1,m W i r i 2 , where W is the weight and r is a residual, equal to the difference between observed and calculated values of the electromotive force EMF, m -number of experimental points, n -number of refined parameters.…”

Structural characterization, ROS-inductive and proteasome inhibitory properties of ternary and binary copper(II) complexes of N2- and N2O2-ligands

“…The broad, relatively weak bands of the aqueous solutions of the copper(II) complexes, 1 and 2 ( Table 1) are characteristic of d-d transitions known for hexacoordinated copper(II) complexes with distorted octahedral geometry and where parity-forbidden Laporte selection rules operate to disallow intense d-d transition [55,56]. Both complexes 3 and 4 have significantly higher molar absorptivities (about 90-170 mol À1 dm 3 cm À1 ), suggesting strong tetragonal distortion of the octahedron or square pyramidal geometry where parity-forbidden Laporte selection rules are relaxed by lowered symmetry [57].…”