You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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What is the molecular formula of the compound with this IUPAC name (2S,3aS,7aS)-1-(quinoxaline-2-carbonyl)-2,3,3a,4,5,6,7,7a-octahydroindole-2-carboxylic acid ?
user
C18H19N3O3
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