Aminopyrazine analogues as chemiluminescence derivatization reagents for pyruvic acid

Aminopyrazine analogues were studied as sensitive and selective chemiluminescence derivatization reagents for pyruvic acid. These analogues reacted with pyruvic acid under acidic conditions at 100 degrees C to produce Cypridina luciferin derivatives, which exhibit chemiluminescence by reaction with hydrogen peroxide in the presence of potassium t-butoxide in dimethylformamide. Of the four aminopyrazine analogues (2-amino-5-phenylpyrazine, 2-amino-5-(4-hydroxyphenyl)pyrazine, 2-amino-5-(3,4, 5-trimethoxyphenyl)pyrazine, and 2-aminoquinoxaline), in the present test 2-amino-5-(3,4,5-trimethoxyphenyl) pyrazine was the most sensitive for pyruvic acid, and the chemiluminescence intensity was about four times higher than that obtained with aminopyrazine.