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-[(2S)-2-(furan-2-yl)-2-pyrrolidin-1-ium-1-ylethyl]-3-[4-(trifluoromethoxy)phenyl]thiourea is given. What is its corresponding molecular formula?
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C18H21F3N3O2S+
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