Synthesis and antibacterial property of polyamide dendrimers based on tetraethyl-1,1,3,3-propanetetracarboxylate

In this study, a new family member of polyamide dendrimers which is based on the tetraethyl-1,1,3,3-propane tetra carboxylate was synthesized via a multi-step divergent approach. Initially, the tetraethyl-1,1,3,3-propane tetra carboxylate was synthesized through the reaction which was between the substituted malonic ester and the methylene bromide. The product was further modified through the reaction of 1,6-diamino hexane to prepare the core of the dendrimer; generation zero (G₀), with tetra-amino functional groups. These amino groups have been employed in two consecutive amidification reactions. The first was with the adipoyl chloride. The second one was with Tris(hydroxymethyl) aminomethane fabricate the first generation (G₁) with the branching points. Similarly, the second (G₂), fourth (G₄), and sixth (G₆) generations were fabricated via multiple consecutive esterifications and amidification reactions. The progress of the dendrimers generation growth was monitored by ¹H-NMR, ¹³C-NMR, FTIR, and UV–vis. Subsequently, the antimicrobial activity of the produced polyamide dendrimers were investigated, against gram-positive staphylococcus arouse (S. arouse) and gram-negative Escherichia coli (E. coli) bacteria. The results showed that G₆NH₂ had the highest antimicrobial activity against S. arouse and E. coli.