You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (E)-N-[8-bromo-1-(3-methoxypropyl)-2-oxo-[1]benzofuro[3,2-d]pyrimidin-4-yl]-2-(methyliminomethyl)but-2-enamide .
user
C20H21BrN4O4
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