Synthesis And Study Of Novel Bisquaternary Ammonium Salts With Nitrogen-Containing Heterocycles

Bisquaternary ammonium salts with nitrogen-containing heterocycles,as a special class of cationic Gemini surfactants,have been widely used in gene transfection,metal corrosion resistance,bacteriostasis and sterilization,the preparation of novel materials,and so on.In this thesis,eight of bisquaternary ammonium salts with urea as a linking group have been synthesized and charaterized,which have not been reported in literature.1.Synthesis of novel cationic Gemini surfactants metioned above can be divided into two steps.Firstly,3-aminopyridine,6-amino quinoline,ethyl 2-aminothiazole-5-carboxylate reacted respectively with triphosgene to form three symmetrical urea derivatives.Secondly,novel bisquaternary ammonium salts were synthesized by the reaction of urea derivatives obtained in the first step with alkylation agents(1-bromooctane,1-bromodecane,1-bromododecane,1-bromotetradecane)respectively.The reaction conditions were optimized.The structures of the synthesised compounds were characterized by FTIR,1H NMR,13C NMR and ESI-MS.2.Since of good solubility of pyridinium cationic Gemini surfactants in water,we investigated the surface properties and aggregation behavior of these compounds by DLS and TEM.3.In addition,the preliminary tests were carried out on antibacterial activity of pyridinium cationic Gemini surfactants against E.coli.