Antibacterial action of sulfa-Co(II) complexes: structure-activity relationship

MONTI, L.; HURE, E.; MOSCONI, N.; TROSSERO, C.; GORR, C.; PONTORIERO, A.; LIMA, B.; FERESIN, G.; TAPIA, A.; RIZZOTTO, M.

BIOCELL

Año: 2008 vol. 32 p. 18 - 18

0327-9545

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} a:link, span.MsoHyperlink {color:blue; text-decoration:underline; text-underline:single;} a:visited, span.MsoHyperlinkFollowed {color:purple; text-decoration:underline; text-underline:single;} @page Section1 {size:595.3pt 841.9pt; margin:6.0cm 181.3pt 332.45pt 6.0cm; mso-header-margin:35.45pt; mso-footer-margin:35.45pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> ANTIBACTERIAL ACTION OF SULFA-Co(II) COMPLEXES: STRUCTURE-ACTIVITY RELATIONSHIP 1Monti, Laura; 1Hure, Estela; 1Mosconi, Natalia; 1Trossero, Claudia; 1Gorr, Carolina; 1Pontoriero, Ana; 2Lima, Beatriz; 2Feresin, Gabriela; 2Tapia, Alejandro; 1Rizzotto, Marcela* 1Área Inorgánica, Facultad de Cs. Bioquímicas y Farmacéuticas, UNR, Argentina. 2IBT, UNSJ, San Juan, Argentina * e-mail: mrizzott@fbioyf.unr.edu.ar   Among the many and so different families of organic-inorganic chemicals being currently investigated due to their applications, sulfonamides are part of the outstanding ones. The minimum inhibitory concentration of sulfa-Co(II) complexes (sulfas: sulfanilamide, SA; sodium sulfathiazole, NaST; phthalylsulfathiazole, PhST) was determined with different bacterial strains:  ATCC, Malbrán Institute, Pasteur Institute and Laboratory of Microbiology (LM), Cuyo Univ. Gram (-) strains: Escherichia coli ATCC 25922, LM E. coli and Pseudomonas aeruginosa ATCC 27853. Gram (+) strains: Staphylococcus aureus methicillin-sensitive ATCC 29213 and S. aureus methicillin-resistant ATCC 43300. The Co(II)-SA complex showed higher activity than the ligand against all the tested strains; similar results were showed by Co(II)-ST with P. aeruginosa, but the activity of the Co(II)-PhST complex was always lower than the ligand one. Trying to correlate these results with the structure of each complex, electronic spectra were recorded (solvents: ethanol, DMSO; range: 400-800 nm). The ligand strength in the spectrochemical serie would be in an inverse relationship in respect of the antibacterial power of the respective complex. This results, in conjunction with the analysis of the structure of the ligands and of the Co(II)-ST complex, suggest that the antibacterial power would be related to the coordination of the metal with atoms of N non heterocyclic.