Complexes of 3dn Metal Ions with Thiosemicarbazones: Synthesis and Antimicrobial Activity

Department of Inorganic Chemistry, University of Bucharest, Bucureşti, Bucureşti, Romania
Molecules (Impact Factor: 2.42). 02/2007; 12(4):782-96. DOI: 10.3390/12040782
Source: PubMed


The chelating behavior of the thiosemicarbazone derivatives of 2-hydroxy-8-R-tricyclo[,7)]tridecane-13-one (where R = H, CH3, C6H5) towards Co(II), Ni(II) and Cu(II) has been investigated by elemental analysis, molar conductivity measurements, UV-VIS, IR, ESR spectroscopy and thermal studies. It was deduced from the experiments performed that the ligands coordinate to metal ions in different ways--neutral bidentate or mononegative bidentate--depending on the nature of R. Also, if metal acetates are used instead of metal chlorides, the ligands coordinate in a mononegative bidentate fashion, regardless of the nature of R or the thiosemicarbazone type ligand. The antimicrobial activity of the ligands and of the complexes towards samples of Acinetobacter boumanii, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa was determined.

Download full-text


Available from: Gulea Aurelian
  • Source
    • "The Ni(II) complex that displays three bands at 8213, 15850, and 20430 cm−1 due to 3A2g(F) → 3T2g(F)(ν1), 3A2g(F) → 3T1g(F)(ν2), and 3A2g(F) → 3T1g(P)(ν3) transitions reveals the octahedral geometry around the Ni(II) ion [31]. The Mn(II) complex that exhibits bands at 10120, 19010, and 21820 cm−1 assigned due to 6A1g → 4T1g(ν1), 6A1g → 4T2g(ν2), and 6A1g → 4Eg(ν3) transition indicates the coordinated octahedral geometry [32]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: A simple condensation of 3-amino-2-methylquinazoline-4-one with 2-hydroxy-1-naphthaldehyde produced new tridentate ONO donor Schiff base ligand with efficient yield. The structural characterization of ligand and its Cu(II), Ni(II), Co(II), Mn(II), Zn(II), and Cd(II) complexes were achieved by the aid of elemental analysis, spectral characterization such as (UV-visible, IR, NMR, mass, and ESR), and magnetic data. The analytical and spectroscopic studies suggest the octahedral geometries of Cu(II), Co(II), Ni(II) and Mn(II) complexes and tetrahedral geometry of Zn(II) and Cd(II) complexes with the tridentate ONO Schiff base ligand. Furthermore, the conclusions drawn from these studies afford further support to the mode of bonding discussed on the basis of their 3D molecular modeling studies by considering different bond lengths, bond angles, and bond distance. The ligand and its metal complexes evaluated for their antimicrobial activity against Staphylococcus aureus (MTCC number 7443), Bacillus subtilis (MTCC number 9878), Escherichia coli (MTCC number 1698), Aspergillus niger (MTCC number 281), and Aspergillus flavus (MTCC number 277). The MIC of these compounds was found to be most active at 10 μg/mL concentration in inhibiting the growth of the tested organisms. The DNA cleavage activity of all the complexes was studied by gel electrophoresis method.
    Full-text · Article · Feb 2014 · The Scientific World Journal
  • Source
    • "In recent years, sulfur containing ligands such as dithiocarbamates and thiosemicarbazones and their transition metal complexes have received more attention in the area of medicinal chemistry, due to their pharmacological properties, such as antiviral [1] [2] [3], antibacterial [4] [5] [6] [7], antifungal [8] [9] [10], antiparasitic [11] [12], and antitumor [13] [14] [15] [16] [17] [18] [19] activities. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The palladium(II) bis-chelate complexes of the type [Pd(TSC(1-5))2] (6-10), with their corresponding ligands 4-phenyl-1-(acetone)-thiosemicarbazone, HTSC(1) (1), 4-phenyl-1-(2'-chloro-benzaldehyde)-thiosemicarbazone, HTSC(2) (2), 4-phenyl-1-(3'-hydroxy-benzaldehyde)-thiosemicarbazone, HTSC(3) (3), 4-phenyl-1-(2'-naphthaldehyde)-thiosemicarbazone, HTSC(4) (4), and 4-phenyl-1-(1'-nitro-2'-naphthaldehyde)-thiosemicarbazone, HTSC(5) (5), were synthesized and characterized by elemental analysis and spectroscopic techniques (IR and (1)H- and (13)C-NMR). The molecular structure of HTSC(3), HTSC(4), and [Pd(TSC(1))2] (6) have been determined by single crystal X-ray crystallography. Complex 6 shows a square planar geometry with two deprotonated ligands coordinated to Pd(II) through the azomethine nitrogen and thione sulfur atoms in a cis arrangement. The in vitro cytotoxic activity measurements indicate that the palladium(II) complexes (IC50 = 0.01-9.87 μM) exhibited higher antiproliferative activity than their free ligands (IC50 = 23.48-70.86 and >250 μM) against different types of human tumor cell lines. Among all the studied palladium(II) complexes, the [Pd(TSC(3))2] (8) complex exhibited high antitumor activity on the DU145 prostate carcinoma and K562 chronic myelogenous leukemia cells, with low values of the inhibitory concentration (0.01 and 0.02 μM, resp.).
    Full-text · Article · Dec 2013 · Bioinorganic Chemistry and Applications
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Two variants are discussed of the synthesis of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid β-N-tosylhydrazides which undergo a McFayden-Stevens reaction to give 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbaldehydes in high yields. It was shown that the thiosemicarbazones prepared from them exist in the solid state exclusively in the syn-form while in solution a hydrazone ↔ enhydrazine tautomerism is observed. The results of a study of the antitubercular activity of the synthesized compounds are reported.
    Full-text · Article · Jun 2009 · Chemistry of Heterocyclic Compounds
Show more