Synthesis of Polyfunctionalized Tröger's Base Analogs Derived from Ethacridine (6,9-Diamino-2-ethoxyacridine)

In the search for chemical probes of DNA conformations, we report an efficient synthesis of new Troger's Base analogs derived from polyfunctionalized aminoacridines treated with a stoechiometric amount of formaldehyde in trifluoroacetic acid. For the more sensitive aminoacridines, the Troger's Bases were obtained by nucleophilic substitution of the chloro group of the “pre-formed” corresponding Troger's Base.