You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 4-(4-chlorophenyl)-N'-[2-(1,1-dioxothian-4-yl)ethyl]piperazine-1-carboximidamide;hydroiodide into molecular formula.
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C18H28ClIN4O2S
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