Abstract
We prepared N-alkylated imidazopyrazinone derivatives as a novel fluorescent probe molecule for biological imaging. We found that their UV-vis absorption and fluorescence spectra in the presence of metal ions such as Mg2+, Ca2+, Ba2+, Sc3+ and La3+ showed notable spectral changes caused by metal complex formation. The ability of imidazopyrazinone derivatives to form metal complex was evaluated by semi-empirical molecular orbital calculations. The tendency of the UV-vis absorption spectral shift by complex formation was dependent upon Lewis acidity of each metal ion. This result indicates that imidazopyrazinone derivatives are applicable to an indicator of Lewis acidity.
