You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(cyclopropylmethyl)-2-[2-(3,5-dimethoxybenzoyl)-5-oxa-2-azaspiro[3.4]octan-7-yl]acetamide into its molecular formula.
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C21H28N2O5
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