You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-[(7E)-7-[(4-methoxy-3-nitrophenyl)methylidene]-6-oxo-5H-pyrimido[4,5-b][1,4]thiazin-2-yl]-N-[4-(4-methylpiperazin-1-yl)phenyl]acetamide is given. What is its corresponding molecular formula?
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C27H27N7O5S
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