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 ethyl 4-[2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2-oxoethoxy]-1-(4-nitrophenyl)pyrazole-3-carboxylate ?
user
C21H20N4O6S
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