Synthesis and antimicrobial activity of new beta-hydroxy amino or ammonium trimeric surfactants

MARCELO C. MURGUÍA; MARIANO D. CRISTALDI; AYELÉN PORTO; JOSÉ DI CONZA; RICARDO J. GRAU

Journal of Surfactants and Detergents

Springer

Lugar: Berlin; Año: 2008 vol. 11 p. 41 - 48

1558-9293

Neutral and cationic series of new trimericb-hydroxy amino or ammonium surfactants were synthesizedvia a two-step process involving the Williamsonetherification and regioselective oxirane ring opening withprimary and tertiary amines, which afforded good toexcellent yields. The synthesized compounds wereobtained in high purity by a simple purification procedureon column chromatography. The critical micelle concentration(CMC), effectiveness of surface tension reduction(cCMC), surface excess concentration (C), and area permolecule at the interface (A) were determined and valuesindicate that the cationic series is characterized by goodsurface-active and self-aggregation properties. The antimicrobialactivities are reported for the first time againstrepresentative bacteria and fungi for trimeric compounds.The antimicrobial potency was found to be dependent onthe target microorganism (Gram-positive bacteria[fungi[Gram-negative bacteria), as well as both theneutral or ionic nature (cationic[neutral) and alkyl chainlength (tri-C12[tri-C18[tri-C8) of the compounds. Thetri-C8 and tri-C18 compounds were found to be almostinactive and the tri-C12 compounds, the most potent antimicrobialsurface-active agents from the synthesized series.The trimeric C12 cationic compound was found to becomparable to benzalkonium chloride against Gram-positivebacteria and fungi, in vitro. The antimicrobialeffectiveness of this new compound and the facile two-stepprocedure for synthesizing it with an excellent overall yield(92%) provide a cost effective trimeric gemini surfactant.