You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (3R,6S)-3-[(3-fluorophenyl)methyl]-3-hydroxy-1,4-dimethyl-6-[(4-nitro-1H-indol-3-yl)methyl]piperazine-2,5-dione into its molecular formula.
user
C22H21FN4O5
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