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 (4R,6S)-6-[(E)-2-[2,4-dichloro-6-[(1-oxidopyridin-1-ium-4-yl)methoxy]phenyl]ethenyl]-4-hydroxyoxan-2-one into molecular formula.
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C19H17Cl2NO5
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