3-[[(5-Chloro-2-pyridinyl)amino]carbonyl]-2-pyrazinecarboxylic acid is an impurity of Zopiclone (Z700500, a cyclopyrrolone member of a family of non-benzodiazepine GABAA receptor agonists. This is a controlled substance (depressant) in the US but not in Canada. Sedative, hypnotic.