Discriminating detection between Mg2+ and Ca2+ by fluorescent signal from anthracene aromatic amide moiety

Novel fluorescent reagents 1 and 2 were synthesized. In the absence of metal ions, the fluorescence emissions of these compounds were quite weak, but their intensities were much greater in the presence of alkaline earth metal ions. The peak shape and maximum wavelength of the emission of the complex with Mg2+ differed from those of Ca2+ and other alkaline earth metal ions. The peak wavelength difference was 30 nm.