2,5-PYRAZINEDICARBOXYLIC ACID DIHYDRATE PYRAZINE-2,5-DICARBOXYLIC ACID, DIHYDRATE;2,5-PYRAZINEDICARBOXYLIC ACID DIHYDRATE;2,5-Pyrazinedicarboxylic acid dihydrate,97%;2,5-Pyrazinedicarboxylicaciddehydrate