You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-bromo-N-[2-oxo-2-[(4-thiomorpholin-4-ylphenyl)methylamino]ethyl]thiophene-2-carboxamide into its molecular formula.
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C18H20BrN3O2S2
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