You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 4-(4,5-dichloro-2-cyano-3,6-dioxocyclohexa-1,4-dien-1-yl)-2,3-dihydropyrazine-1-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C14H11Cl2N3O4
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