You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
9H-fluoren-9-ylmethyl N-[(3R)-6-bromo-1-methoxy-2,5-dioxohexan-3-yl]carbamate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H22BrNO5
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