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 [(2S)-1-(2-methoxyethylamino)-1-oxopropan-2-yl] 1-ethyl-3-methyl-2-oxoquinoxaline-6-carboxylate is given. What is its corresponding molecular formula?
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C18H23N3O5
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