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 methyl (4S)-6-amino-4-(2-chloro-7-methoxyquinolin-3-yl)-5-cyano-2-methyl-4H-pyran-3-carboxylate into molecular formula.
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C19H16ClN3O4
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