You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [4-(2-methoxyacetyl)oxyoxolan-2-yl] 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate by IUPAC nomenclature, provide its molecular formula.
user
C21H17ClF3NO9
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