You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3-[4-amino-3-(4-bromophenyl)thieno[3,2-c]pyridin-7-yl]-N-pyridin-3-ylprop-2-enamide into its molecular formula.
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C21H15BrN4OS
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