You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name methyl 2-[[1-carbamoyl-4-[(4-chlorophenyl)methyl]-2,3-dihydro-1H-cyclopenta[b]indol-8-yl]oxy]acetate into its molecular formula.
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C22H21ClN2O4
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