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 (2R)-2-[4-(2-phenoxyethyl)piperazine-1,4-diium-1-yl]-N-propan-2-ylpropanamide is given. What is its corresponding molecular formula?
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C18H31N3O2+2
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