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 [2-[[(1S)-1-(2,5-dimethoxyphenyl)ethyl]amino]-2-oxoethyl]-ethyl-[2-(ethylamino)-2-oxoethyl]azanium is given. What is its corresponding molecular formula?
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C18H30N3O4+
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