Zopiclone N-Oxide (Mixture of diastereomers)

Zopiclone N-Oxide (Eszopiclone Impurity A) (Mixture of Diastereomers)

4-Methyl-1-piperazinecarboxylic acid 6-(5-chloro-2-pyridinyl)-6,7-dihydro-7-oxo-5H-pyrrolo[3,4-b]pyrazin-5-yl ester 4-oxide

1-Piperazine-carboxylic Acid 4-Methyl-4-oxide 6-(5-Chloro-pyridin-2-yl)-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazin-5yl Ester