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 tert-butyl (3R,3'R)-1-methyl-5'-methylidene-2-oxo-3'-thiophen-3-ylspiro[indole-3,2'-oxane]-3'-carboxylate is given. What is its corresponding molecular formula?
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C23H25NO4S
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