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 N-[3-[2-[[N-ethyl-N'-[2-(2-fluorophenyl)ethyl]carbamimidoyl]amino]ethoxy]phenyl]acetamide is given. What is its corresponding molecular formula?
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C21H27FN4O2
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