A series of 3-amino-N-substituted-1,8-naphthalimides and their salicylic Schiff base derivatives were synthesized.
The structure of the obtained compounds was confirmed using 1H and 13C NMR, FT-IR spectroscopy and
elemental analysis and COSY and HMQC for the representative molecules. The photophysical (UV–Vis, PL) and
biological properties of all of the prepared compounds were studied. It was found that the amine with the nhexyl
group in EtOH had the highest PL quantumyield (Ф=85%) compared to the others.Moreover, the chelating
properties of the azomethines with the n-hexyl group (1a, 1b, 1c) were tested against various cations (Al3+,
Ba2+, Co2+, Cu2+, Cr3+, Fe2+, Fe3+,Mn2+, Ni2+, Pb2+, Sr2+ and Zn2+) in an acetonitrile, acetone and PBS/AC mixture.
Compounds that contained the electron withdrawing groups (-Br, -I) had the ability to chelate most of the
studied cations, while the unsubstituted derivative chelated only the trivalent cations such as Al3+, Cr3+ and
Fe3+ in acetonitrile. The effect of the environment on the keto-enol tautomeric equilibrium was also demonstrated,
especially in the case of the derivativewith a bromine atom. The biological studies showed that the tested
molecules had no cytotoxicity. Additionally, the ability to image intracellular organelles such as the mitochondria
and endoplasmic reticulum was revealed. The crucial role of the hydrolysis of imines for cellular imaging was
presented
