Metalloantibiotics: synthesis, characterization and antimicrobial evaluation of bismuth-fluoroquinolone complexes against Helicobacter pylori.

Pharmacy Department, Faculty of Technology and Engineering, The M. S. University of Baroda, Vadodara-390001, India.
Acta Pharmaceutica (Impact Factor: 1.16). 09/2009; 59(3):259-71. DOI: 10.2478/v10007-009-0027-6
Source: PubMed

ABSTRACT Novel organometallic compounds have been prepared by complexing the fluoroquinolones, norfloxacin, ofloxacin, ciprofloxacin, sparfloxacin, lomefloxacin, pefloxacin and gatifloxacin, with bismuth. The complexes were characterized by UV, IR, atomic absorption spectroscopy, elemental analysis, differential scanning calorimetry, thermogravimetric analysis and mass spectrometry. Their antibacterial potential against Helicobacter pylori and other microorganisms was investigated. These compounds were found to possess strong activity against Helicobacter pylori with a minimum inhibitory concentration of 0.5 mg L-1. They also exhibited moderate activity against Escherichia coli, Staphylococcus aureus, Bacillus pumilus and Staphylococcus epidermidis. These bismuth-fluoroquinolone complexes have the potential to be developed as drugs against H. pylori related ailments.

1 Bookmark
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Quinolones are synthetic broad-spectrum antibiotics with good oral absorption and excellent bioavailability. Due to the chemical functions found on their nucleus (a carboxylic acid function at the 3-position, and in most cases a basic piperazinyl ring (or another N-heterocycle) at the 7-position, and a carbonyl oxygen atom at the 4-position) quinolones bind metal ions forming complexes in which they can act as bidentate, as unidentate and as bridging ligand, respectively. In the polymeric complexes in solid state, multiple modes of coordination are simultaneously possible. In strongly acidic conditions, quinolone molecules possessing a basic side nucleus are protonated and appear as cations in the ionic complexes. Interaction with metal ions has some important consequences for the solubility, pharmacokinetics and bioavailability of quinolones, and is also involved in the mechanism of action of these bactericidal agents. Many metal complexes with equal or enhanced antimicrobial activity compared to the parent quinolones were obtained. New strategies in the design of metal complexes of quinolones have led to compounds with anticancer activity. Analytical applications of complexation with metal ions were oriented toward two main directions: determination of quinolones based on complexation with metal ions or, reversely, determination of metal ions based on complexation with quinolones.
    Molecules 09/2013; 18(9):11153-97. · 2.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The present work comprises the synthesis of ofloxacin (OFL) complexes with various transition metals. Two types of complexes [Cu(OFL)Cl2].H2O, [Pt(OFL)CI2].3H2O, [Zn(OFL)2]2CI.4H2O, [Ru(OFL)2ClH2O]2CI.4H2O, and [Fe(OFL)2Cl]2CI.5H2O were obtained. The complexes were characterized by different physicochemical, spectroscopic, and elemental analysis. The thermal decomposition behaviors of metal complexes were investigated in nitrogen atmosphere using TG and DTA techniques. Results suggest that OFL interacts with the metals as a monoanionic bidentate ligand. These complexes were also tested for their antibacterial activity against nine different microorganisms, and the results were compared with the parent drug. The electrochemical properties of all complexes have been investigated by cyclic voltammetry using glassy carbon electrode. The oxidation/reduction of metal complexes was irreversible/reversible and exhibited diffusion controlled process depending on pH. The dependence of intensities of currents and potentials on pH, concentration, scan rate, nature of the buffer was investigated. The oxidation/reduction mechanism was proposed and discussed. The DNA binding activity of the complexes was evaluated by examining their ability to bind to calf-thymus DNA (CT DNA) with UV spectroscopy. UV studies of the interaction of the OFL and complexes with DNA have shown that these compounds can bind to CT DNA. The binding constants of the OFL and complexes with CT DNA have also been calculated.
    Synthesis and Reactivity in Inorganic Metal-Organic and Nano-Metal Chemistry 06/2014; 44(10). · 0.52 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: : Bismuth compounds have been used extensively as medicines and in particular for the treatment of gastrointestinal ailments. In addition to bismuth's well known gastroprotective effects and efficacy in treating H. pylori infection it also has broad anti-microbial, anti-leishmanial and anti-cancer properties. Aspects of the biological chemistry of bismuth are discussed and biomolecular targets associated with bismuth treatment are highlighted. This review strives to provide the reader with an up to date account of bismuth-based drugs currently used to treat patients and discuss potential medicinal applications of bismuth drugs with reference to recent developments in the literature. Ultimately this review aims to encourage original contributions to this exciting and important field.
    Molecules 09/2014; 19(9):15258-15297. · 2.10 Impact Factor

Full-text (2 Sources)

Available from
May 29, 2014