2-Pyrazine carboxylic acid 2-Pyrazinecarboxylic acid 2-Pyrazinoic acid 98-97-5 EINECS 202-718-1 NSC 13146 Paradiazinecarboxylic acid Piazinecarboxylic acid Pyrazine-2-carboxylic acid Pyrazinecarboxylic acid Pyrazinemonocarboxylic acid Pyrazinic acid Pyrazinoic acid