2-Aminobenzaldehyde, a common precursor to acridines and acridones endowed with bioactivities

Abstract By starting from a common substrate, 2-aminobenzaldehyde, both acridines and acridones were prepared. The former were generated in high yields by copper-catalyzed N-arylation followed by acid-mediated cyclization while the latter were obtained by double copper-catalyzed N-arylation followed by cyclization under the same reaction conditions. Moreover, acridine was subjected to deprotometalation by recourse to a lithium-zinc base and converted to the corresponding 4-iodo derivative, which was involved in copper-catalyzed couplings with pyrrolidinone and pyrazole. Finally, addition of pyrazole, indole and carbazole onto the 9 position of bare acridine was improved. While moderate biological activity was noticed in melanoma cells growth inhibition, the newly prepared compounds feature interesting photophysical properties which were evaluated in a preliminary study.