You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named N-(3,5-dimethylphenyl)-2-[(1R,2S,6S,7R,8S,10S)-3,5-dioxo-4-azatetracyclo[5.3.2.02,6.08,10]dodec-11-en-4-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C21H22N2O3
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