Synthesis and microbiological properties of novel bis-quaternary ammonium compounds based on 4,4′-oxydiphenol spacer

Novel gemini (tail–head–spacer–head–tail) bis-quaternary ammonium compounds with a 4,4′-oxydiphenol spacer between two pyridinium heads were synthesized and compared with commonly used antiseptics such as benzalkonium chloride and chlorhexidine gluconate. Analogues bearing CH, CH and CH aliphatic groups displayed potent broad spectrum in vitro activity against five bacterial strains and two fungi, with minimum inhibtory concentrations relatively independent of the counter ion