Synthesis and antimicrobial properties of binaphthyl derived quaternary ammonium bromides

(S)-N-(2-(4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepin-1-yl)ethyl)-N, N-dimethyl-N-dodecyl ammonium bromide (S)-1a and (S)-N-(2-(4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepin-1-yl)ethyl)-N, N-dimethyl-N-tetradecylammonium bromide (S)-1b have been synthesized as optically active quaternary ammonium salts starting from 1,1'-binaphthyl-2,2'-diol. Their antimicrobial activity expressed as minimal inhibition concentration (MIC) was tested against Gram-positive human pathogenic bacteria S. Aureus, Gram-negative bacteria E. coli and human fungal pathogen C. Albicans.