3,7‐Bis(N‐methyl‐N‐phenylamino)phenothiazinium Salt: Improved Synthesis and Aggregation Behavior in Solution

Abstract

In this paper, the optimization of the synthesis of 3,7‐bis(N‐methyl‐N‐phenylamino)phenothiazinium chloride with a detailed analysis of reaction parameters, i.e. solvent, temperature, amount of amine, as well as addition of a non‐nucleophilic base, is presented. Spectroscopic, electrochemical and computational data show that the presence of the two phenyl rings, directly bound on the PTZ+ core, inhibits the aggregation ability of the salt at concentrations up to 10–3 M. Furthermore, the introduction of an aromatic group in phenothiazinium‐based molecules appears strategic to introduce other useful functionalities, thus opening new opportunities in the drug design/discovery research field.