You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[(E)-[4-(2,3-dihydro-1,4-benzodioxin-6-ylamino)-4-oxobutan-2-ylidene]amino]-3,4-dimethoxybenzamide into its molecular formula.
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C21H23N3O6
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