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 methyl N-(spiro[5,7-dihydro-[1,3]dioxolo[4,5-g]isochromene-8,3'-cyclohexene]-7-ylmethyl)carbamate is given. What is its corresponding molecular formula?
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C18H21NO5
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