Thermodynamic Investigation and Mixed Ligand Complex Formation of 1,4-Bis-(3-aminopropyl)-piperazine and Biorelevant Ligands

Abstract

Thermodynamic parameters for protonation of 1,4-bis(3-aminopropyl)-piperazine (BAPP) and its metal complexation with some divalent metal ions were determined in aqueous solution at constant ionic strength (0.1 M NaNO3) using a potentiometric technique. The order of –ΔG0 and –ΔH0 was found to obey Co2+ < Ni2+ < Cu2+ > Zn2+, in accordance with the Irving-Williams order. The formation equilibria of zinc (II) complexes and the ternary complexes Zn(BAPP)L, where L = amino acid, amides, or DNA constituents), have been investigated. Ternary complexes are formed by a simultaneous mechanism. The concentration distribution of the complexes in solution was evaluated as a function of pH. Stoichiometry and stability constants for the complexes formed are reported and discussed. The stability of ternary complexes was quantitatively compared with their corresponding binary complexes in terms of the parameter Δlog K.

Synthesis, Characterization and Antibacterial Activity of Schiff Base, 4-Chloro-2-{(E)-[(4-Fluorophenyl)imino]methyl}phenol Metal (II) Complexes

“…is was a shift towards longer wavelength with respect to the spectrum of the Schiff base ligand. e band at 249.1 nm was due to intraligand transition, and the band at 401.9 nm was as a result of d-d transition for 3 T 1g (F) ⟶ 3 T 2g which is within the range for octahedral configuration as reported in many octahedral cobalt (II) complexes [20][21][22]. e electronic spectrum of Ni (II) complex showed three bands at 245.2 nm (40783.03 cm −1 ), 325.1 nm (30759.77 cm −1 ), and 421.9 nm (23702.30 cm −1 ).…”

Appraisal of ionic behaviors of aqueous sodium and potassium valinate conductometrically

“…Metal salt of these amino acid affects the solubility and conductivity. Conductometric investigation received more attention of researchers for molecular interactions investigation at various concentration and different temperatures [8][9][10][11][12][13] by using different types of molecules. Ionic behavior of sodium and potassium salts valinate were not yet been discussed in the literature at a lower concentration range and different temperatures conductometrically.…”

To investigate the thermodynamic parameters of Li, Na and K salt of L leucinate at various temperature and concentration by conductometric measurement

“…Metal salt of this amino acid affects the solubility and conductivity. Conductometric investigation received more attention of researchers for molecular interactions investigation at various concentration and different temperatures by using different types of molecules [7][8][9][10][11][12][13].…”