You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 8-[2-[2-[8-(9H-fluoren-9-ylmethoxycarbonylamino)-9-[(2-methylpropan-2-yl)oxy]-5,9-dioxononoxy]ethoxy]ethoxy]-4-oxooctanoic acid by IUPAC nomenclature, provide its molecular formula.
user
C40H55NO11
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