Synthesis and the anti-microbial activity of multiple quaternary ammonium chlorides

A series of new cationic surfactants, bis-quaternary ammonium and tris-quaternary ammonium chlorides, were prepared from N,N-dimethyldodecylamine and a product of the reaction of epichlorohydrin with ethyl-, propyl-, butyl-, pentyl-, hexyl- and octylamine (in the case of bis-ammonium salts) or hydrochloride of diethyl-, dipropyl-, dibutyl or dihexylamine (in the case of tris-ammonium salts). All these surfactants have good water solubility and low critical micelle concentrations of more than one order of magnitude lower than these of corresponding mono-alkylammonium salts. The anti-microbial activity against bacteria: S. aureus, B. subtilis, E. coli, S. marcescens and yeasts: R. rubra and C. albicans was determined. Many of these compounds showed anti-microbial activities against gram-positive bacteria and yeast, but they were not active against gram-negative bacteria.