Characterization, kinetics of thermal decomposition and molecular modeling studies on mercury (II) complexes of biologically active glutathione

Abstract

Mercury (II) complexes of reduced glutathione (GSH) of general composition [Hg(L)(X)]H 2 O, SCN 7 , CH 3 CO 2 7 , Cl 7 ) have been synthesized and characterized by elemental analysis, infrared spectra and electronic spectral studies. The stability constant of the mercury complex has been evaluated potentiometrically, and thermogravimetric (TG) and differential thermal analytical (DTA) studies have also been carried out for these complexes. Infrared spectra indicate deprotonation and coordination of cysteinyl sulfur with the metal ions. It indicates the presence of water molecules in all the complexes which has been supported by TG and DTA studies. The thermal behavior of complexes shows that the water molecule is removed in first step, followed by the removal of anions and then decomposition of the ligand molecule in subsequent steps. General mechanisms describing the decomposition of the solid complexes are suggested. Kinetic and thermodynamic parameters were computed from the thermal decomposition data. The geometry of the metal complexes has been optimized with the help of molecular modeling.

Synthesis, Structural Characterization, and Antimicrobial Activities of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) Complexes of Triazole-based Azodyes

“…The mass spectra of the complexes 4-8 showed the highest peaks corresponding to their molecular weights, based on the atomic weights of 63 Cu, 64 Zn, 55 Mn, 59 Co and 58 Ni isotopes; among several molecular weights based on the isotope distribution of the metal. 56 The spectrum of Cu(II)-complex 4 displays isotope cluster peaks at m/z 396.…”

“…64 The mechanism and the thermodynamic parameters (E*, ∆H*, ∆G*, ∆S* and lg A) of the decomposition steps are affected by the nature of metal ion and the structure of ligand used for preparing the metal ion complex.…”

Spectroscopic and thermal investigations of complexes of CrIII, MnII, ZnII & CdII - carboxamide

“…Recently, there has been increasing interest in determining the rate-dependent parameters of solidstate non-isothermal decomposition reactions by analysis of TG curves [23,24]. Thermogravimetric (TG) and differential thermogravimetric (DTA) analyses were carried out for different metal-Amide complexes in ambient conditions (Figure 4a-d).…”

Nickel(II) complexes of new polydentate carboxyamide: spectroscopic, kinetics of thermal decomposition and X-ray powder diffraction studies

“…Recently, there has been increasing interest in determining the rate-dependent parameters of solid-state non-isothermal decomposition reactions by analysis of TG curves [25,26]. Thermogravimetric (TG) and differential thermogravimetric (DTA) analyses were carried out for Ni II -Amide complexes in ambient conditions ( Figure 11: Thermogram of complexes).…”