Antistaphylococcal activity of polychlorinated N-arylcinnamamides

Mutant strains of Staphylococcus aureus resistant to methicillin (MRSA) became widespread throughout the world at the end of the 20^th century. Unfortunately, in recent years, individual cases of vancomycin-resistant S. aureus (VRSA) have also begun to appear. For that reason, the search and development of new active compounds is still needed. A series of newly synthesized ring-substituted (2E)-3-(3,4-dichlorophenyl)-N-arylprop-2-enamides was tested for their antimicrobial effect against control strain S. aureus ATCC 29213 and three isolates of MRSA. The microdilution method was used to determine minimum inhibitory concentration. Three derivatives substituted by a trifluoromethyl moiety on the anilide ring were chosen and analyzed in this contribution. This electron-withdrawing substituent has been shown several times to carry an antibacterial effect against MRSA. Two of the tested compounds have comparable or higher activity than that of the standard antibiotic ciprofloxacin. This study was supported by Palacky University Olomouc (IGA_PrF_2020_023).