You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule ethyl (2E,7S)-5-methyl-2-[(5-nitrofuran-2-yl)methylidene]-7-(3-nitrophenyl)-3-oxo-7H-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate into molecular formula.
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C21H16N4O8S
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