You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (E)-N-[4-chloro-3-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-yl)phenyl]-3-quinoxalin-2-ylprop-2-enamide into molecular formula.
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C24H21ClN6O
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