title: Drug resistance modulation in Staphylococcus aureus, a new biological activity for mesoionic hydrochloride compounds.
abstract: Two salts of the mesoionic compounds 1,4-diphenyl-5-(5-nitro-2-furanyl)-1,3,4-thiadiazolium-2-thiol chloride (MC-1) and 4-phenyl-5-(5-nitro-2-furanyl)-1,3,4-thiadiazolium-2-phenylamine chloride (MC-2) were synthesized utilizing 1,4-diphenyl-thiosemicarbazide and 5-nitro-2-furoyl chloride as starting materials. Their structures were characterized by IR, ¹H-NMR, ¹³C-NMR and elemental analysis. These compounds were analyzed for their influence on the effectiveness of norfloxacin, tetracycline, and erythromycin (standard antibiotics) against resistant strains of Staphylococcus aureus. MC-1 and MC-2, at sub-inhibitory concentrations of 16 μg/mL, favourably modulated the antibiotic activity of tetracycline by 16- and 32-fold, respectively (MIC), and that of erythromycin by 4-fold.
authors.affiliation: Department of Chemistry, Federal University of Paraíba, 58059 João Pessoa, PB, Brazil.
authors.forename: Cledualdo Soares
authors.initials: CS
authors.lastname: de Oliveira
authors.forename: Vivyanne dos Santos
authors.initials: Vdos S
authors.lastname: Falcão-Silva
authors.forename: José Pinto
authors.initials: JP
authors.lastname: Siqueira
authors.forename: David Peter
authors.initials: DP
authors.lastname: Harding
authors.forename: Bruno Freitas
authors.initials: BF
authors.lastname: Lira
authors.forename: Jorge Gonçalo Fernandes
authors.initials: JG
authors.lastname: Lorenzo
authors.forename: José Maria
authors.initials: JM
authors.lastname: Barbosa-Filho
authors.forename: Petrônio Filgueiras
authors.initials: PF
authors.lastname: de Athayde-Filho
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002712:Chlorides / Q000737:chemistry / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D013055:Spectrophotometry, Infrared; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D002712:Chlorides