You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 7-[(E)-3-(3,6-dihydro-2H-pyridin-1-yl)-3-oxoprop-1-enyl]-2-propan-2-yl-4H-pyrido[3,2-b][1,4]oxazin-3-one into its molecular formula.
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C18H21N3O3
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