You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-[(2-methoxyphenyl)methyl]-2-[(1S,9R)-8-oxa-2,3,4,12-tetrazatricyclo[7.4.0.02,6]trideca-3,5-dien-12-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
user
C18H23N5O3
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