You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[2-hydroxy-2-(3-methoxyphenyl)ethyl]-2-[[4-(trifluoromethoxy)phenyl]methyl]guanidine;hydroiodide into its molecular formula.
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C18H21F3IN3O3
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