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What is the molecular formula of the compound with this IUPAC name N-(3,4-dichlorophenyl)-3-[(1S,2R,6S,7R,8S,10S)-3,5-dioxo-4-azatetracyclo[5.3.2.02,6.08,10]dodec-11-en-4-yl]propanamide ?
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C20H18Cl2N2O3
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