Abstract Seven betaines were prepared by condensation of N, N'-diphenylamidines with malonic acid derivatives. The amidines were made via a multistep synthesis, starting from their corresponding fatty acids. Malonyl chloride and dipentachlorophenyl phenylmalonate, two derivatives of malonic acid, were obtained from malonic acid and benzyl chloride, respectively. Most of the products were characterized by IR, UV, 1H and 13C NMR. ...