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 1-[2-(3,4-dimethoxyphenyl)ethyl]-3-[7-(dimethylamino)heptyl]-2-methylguanidine;hydroiodide is given. What is its corresponding molecular formula?
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C21H39IN4O2
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