You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named methyl (2R)-2-[2-chloro-4-[[(1R,2R,6S,7R)-3,5-dioxo-4-azatricyclo[5.2.1.02,6]dec-8-en-4-yl]iminomethyl]phenoxy]propanoate by IUPAC nomenclature, provide its molecular formula.
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C20H19ClN2O5
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