Imidazopyrazinone-bioluminescence

Cypridina luciferin is an imidazopyrazinone involved in the bioluminescence of the crustacean Cypridina (Vargula) hilgendotfii. The first total synthesis of this natural product was achieved by Kishi in 1966, which was followed by that of White and Karpetsky in 1971. Most recently, Nakamura et al. developed a convenient, direct procedure for this synthesis, employing Suzuki coupling (Eq. (36)) [67]. 

In recent decades, colorimetric and fluorometric sensors have been used in various scientific fields. In biology, for instance, such sensors are useful reagents for living cell imaging. It is important to design novel sensors because they have the potential to overcome many technical limitations in experiments. Imidazo[l,2-a]pyrazin- 3(7H)-one (imidazopyrazinone) often is used as a bioluminescent substrate, and it is an attractive core structure for useful sensors. In this regard, a new series of imidazopyrazinones [7-benzylimidazo[l,2 a]pyrazin-3(7H)-one derivatives] have been prepared and their fluorescent properties in the presence of various metal ions (Mn+) have been studied (Hirano, et al., 2010). 

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