Anti-Staphylococcus aureus Methicillin-Resistant (MRSA) Activity of a Novel 3-Chalcogenyl Indole
Objective: the development of new drugs against Methicillin-resistant Staphylococcus aureus is a priority to the World Health Organization. So, the objective of this study was to evaluate the antibacterial activity and toxicity of 5-bromo-3-((4-methoxyphenyl) sulfenyl)-1H-indole (3b) against MRSA.Methods: minimum inhibitory concentration (MIC) of 3b was determined against S. aureus ATCC 29213 and 43 clinical isolates. The time-kill assay was performed for 9 isolates. Analysis of variance followed by the post hoc Bonferroni test was used for the statistical tests.Results and conclusions: the MIC50 and MIC90 of 3b were 4 μg.mL-1 and 16 μg.mL-1 respectively. In time-kill assay, the 3b showed bactericidal activity to all evaluated isolates at concentrations of 1xMIC and 2xMIC and the re-growth effect was not observed. About the toxicity tests, 3b has not presented cytotoxicity, mutagenicity, or allergenicity. 3b had particularly good activity against MRSA demonstrating high potential for the development of new antimicrobials products.