You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 5-(difluoromethoxy)pyrazine-2-carboxylic acid;methyl 5-(difluoromethoxy)pyrazine-2-carboxylate;methyl 6-oxo-1H-pyrazine-3-carboxylate ?
user
C19H16F4N6O9
assistant