New quaternary ammonium polymers as antimicrobial agents. Part II. Alkylation products of linear aliphatic poly (aminodisulfides)

Two new polymeric disulphides containing t-amino groups in their main chain, namely poly[1,8-(3,6-dimethyl-3,6-diaza) octaine diyl disulphide] (5) and poly[1,8-(1,12-(3-10-dimethyl-3,10-diaza) dodecane diyl disulphide] (6) were prepared by the polyoxidation of 3,6-dimethyl-3,6-diazaoctane-1,8-dithiol (3) and 3,10-dimethyl-3,10-diazadodecane-1,12-dithiol (4), respectively. They were quaternized with methyl iodide and benzyl bromide, and the resulting quaternary ammonium polymers were preliminarily tested for antimicrobial activity against Escherichia coli K12, Pseudomonas aeruginosa, and Staphylococcus aureus. All the quaternized products showed interesting killing potency against P. aeruginosa. The benzylated products, besides being more active against P. aeruginosa, showed fair activity also against the other bacterial strains tested.