Synthesis and Antibacterial Activity of Quaternary Ammonium Salt-Type Antibacterial Agents with a Phosphate Group

Quaternary ammonium salts are frequently used as antibacterial agent that disrupts cell membrane through the binding of their ammonium cations to anionic sites in the outer layer tissue of bacteria. This article describes the synthesis of quaternary ammonium salt-type antibacterial agents with a phosphate group that strongly binds to hydroxyapatite and bromide ion as counterion. Evaluation of the antibacterial activity of the synthesized compounds in terms of minimum inhibitory concentration (MIC test) showed that the compounds exhibit an excellent antibacterial activity on a variety of bacteria including Gram-positive and Gram-negative bacteria, yeast, and fungi.