Antituberculosis, antifungal and thermal activity of mixed ligand transition metal complexes

Abstract

Mixed-ligand complexes of the type [M(CQ)(Ph)(OH)(H 2 O)], where M = Cu(II), Ni(II), Co(II) and Mn(II), have been investigated. Furthermore, there has been some additional work investigating the effect of metal ions on biological activity. Aiming to obtain novel transition metal complexes that exhibit biological activity, we have synthesized mixed ligand complexes using clioquinol (5-chloro-7-iodo-8-hydroxyquinoline) and 1,10-phenanthroline as ligands. The compounds were characterized using IR, FAB mass spectroscopy, elemental analyses, electronic spectra, magnetic measurements and gravimetric analyses. The kinetic parameters such as order of reaction, the energy of activation, the pre-exponential factor, activation entropy, activation enthalpy and free energy of activation have been reported. The complexes show antituberculosis and antifungal (minimal inhibitory concentration) activities.

8-Hydroxyquinolines: a review of their metal chelating properties and medicinal applications

“…In fact, more than 200 8HQ-like compounds were identified to have an inhibitory effect against replicating TB 112. Results showed that 8HQ itself exerted the most potent activity among other compounds in its class 113. 8HQ can kill both replicating and nonreplicating TB in vitro, with a more potent effect noted for the nonreplicating type 109.…”

“…The antitubercular activity of CQ-metal complexes were also reported 113. In particular, a series of mixed ligand metal complexes using CQ and 1,10-phenanthroline as ligands to coordinate with transition metal ions were synthesized and tested for antitubercular and antifungal activities 113.…”

“…In particular, a series of mixed ligand metal complexes using CQ and 1,10-phenanthroline as ligands to coordinate with transition metal ions were synthesized and tested for antitubercular and antifungal activities 113. It was found that the Mn(II) complex was active against TB (MTCC200) with comparable MIC to the standard drug rifampicin with MIC values of 45 μg/mL and 40 μg/mL, respectively,113 whereas the Co(II) complex showed more potent activity with MIC 6.4-fold less than that of rifampicin 113. This study showed that free ligands and metal complexes exerted higher antitubercular activity than that of metal salts 113…”

Thermal decomposition and mass spectra of mixed ligand copper(II) complexes of 1,10-phenanthroline and coumarin derivatives

“…The thermal behaviors of the obtained complexes were also investigated. The thermal analysis techniques, such as thermogravimetry (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC), were widely applied in studying the thermal behavior and the structure of metal complexes [14][15][16][17][18][19][20][21][22][23][24][25]. The results allowed us to acquire information concerning the structure of these compounds, including their thermal behavior and decomposition.…”

Synthesis, Structure, and Characterization of a Novel One-Dimensional Mixed-Ligand Coordination Polymer of Copper(II)

“…[2] It was not until recently that stacking involving metal chelate rings has been recognized as an important factor influencing the crystal structure of metal-organic compounds; on this point, the copper(II)-carboxylate complexes with suitable Nheterocyclic auxiliary ligands are of interesting because the metal-N-heterocyclic chelate ring could exhibit some degree of "metalloaromaticity." [3][4][5][6][7][8][9][10][11][12][13][14][15] This classic concept was proposed a long time ago and it was recently reviewed and improved by H. Masui. [16,17] The increasing interest in this subject arises from its usefulness as a unifying approach for the reactivity, magnetic, spectral properties, and structure of so-called "metalloaromatic compounds."…”