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 (3S)-N-[(R)-(3-methyl-1,2,4-oxadiazol-5-yl)-(oxan-4-yl)methyl]-2,3-dihydro-1-benzofuran-3-carboxamide is given. What is its corresponding molecular formula?
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C18H21N3O4
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