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 2,3-diethyl-N-(imidazo[1,2-a]pyridin-2-ylmethyl)quinoxaline-6-carboxamide is given. What is its corresponding molecular formula?
user
C21H21N5O
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