RESUMO
The emergence of old and new antibiotic resistance created in the last decades revealed a substantial medical need for new classes of antimicrobial agents. The antimicrobial activity of sulfa drugs is often enhanced by complexation with metal ions, which is in concordance with the well-known importance of metal ions in biological systems. Besides, sulfonamides and its derivatives constitute an important class of drugs, with several types of pharmacological agents possessing antibacterial, anti-carbonic anhydrase, diuretic, hypoglycemic, antithyroid, antiviral and anticancer activities, among others. The purpose of this work has been the obtainment, characterization and determination of biological properties (antibacterial, antifungal, mutagenicity and phytotoxicity) of a new Co(III)-sulfathiazole complex: Costz, besides of its interaction with bovine serum albumin (BSA). The reaction between sodium sulfathiazole (Nastz) and cobalt(II) chloride in the presence of H2O2 leads to a brown solid, [CoIII(stz)2OH(H2O)3], (Costz). The structure of this compound has been examined by means of elemental analyses, FT-IR, 1H NMR, UV-Visible spectrometric methods and thermal studies. The Co(III) ion, which exhibits a distorted octahedral environment, could coordinate with the N thiazolic atom of sulfathiazolate. The complex quenched partially the native fluorescence of bovine serum albumin (BSA), suggesting a specific interaction with the protein. The Costz complex showed, in vitro, a moderate antifungal activity against Aspergillus fumigatus and A. flavus. As antibacterial, Costz displayed, in vitro, enhanced activity respective to the ligand against Pseudomonas aeruginosa. Costz did not show mutagenic properties with the Ames test. In the Allium cepa test the complex showed cytotoxic properties but not genotoxic ones. These results may be auspicious, however, further biological studies are needed to consider the complex Costz as a possible drug in the future.
Assuntos
Cobalto/química , Complexos de Coordenação/síntese química , Sulfatiazóis/química , Allium/efeitos dos fármacos , Allium/crescimento & desenvolvimento , Animais , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Aspergillus fumigatus/efeitos dos fármacos , Bovinos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Peróxido de Hidrogênio/química , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Ligação Proteica , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , SulfatiazolRESUMO
The synthesis and microbiological evaluation of two new Ag(I) complexes with sulfamoxole (SMX), [Ag2(SMX)2]·H2O and [Ag4(SCN)3(SMX)]·H2O are described. Both were characterized by elemental analysis, thermogravimetry, powder and single crystal X-ray diffraction, NMR, Raman and experimental and theoretical IR spectroscopies. Their antibacterial and antifungal properties were evaluated by agar and broth dilution assays, respectively. In addition, synergism tests for Pseudomonas aeruginosa were performed, and genotoxicity studies were carried out employing the Allium cepa test. Both complexes displayed good activity against Escherichia coli, Staphylococcus aureus, P. aeruginosa, and 10 fungi strains, with lower minimum inhibitory concentrations (MICs) than that of free SMX in all cases. The nanometrical crystallite particle size determined from XRPD, DLS and TEM might explain the good microbiological activity in spite of the low solubility of both complexes. The fractional inhibitory concentration (FIC) calculated from the P. aeruginosa test data indicated that the activity of the complexes is not due to synergism of the free components in the concentration ratios studied. Moreover, none of the complexes displayed cytotoxic effects on onions in the concentration range tested, and chromosome aberrations were not observed.
Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Complexos de Coordenação/síntese química , Sulfamoxol/síntese química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Complexos de Coordenação/farmacologia , Cristalografia por Raios X , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Nanopartículas/química , Nanopartículas/ultraestrutura , Cebolas/citologia , Cebolas/efeitos dos fármacos , Cebolas/crescimento & desenvolvimento , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Sulfamoxol/farmacologiaRESUMO
The reaction between phthalylsulfathiazole (H(2)PST), in alkaline aqueous solution, and cobalt(II) nitrate led to a pink solid, [Co(PST)(H(2)O)(4)] (1), which was characterized by elemental and thermogravimetric analysis; FT-IR, Raman and diffuse reflectance spectra. Spectroscopic data reveal that the ligand would be doubly deprotonated and that the Co(II) ion environment is a distorted octahedral one. (1) showed antibacterial activity similar to the ligand.