You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N'-[4-[(1S)-1-aminoprop-2-enyl]-6-chloro-1-[(4-fluoro-3,5-dimethylphenyl)methyl]benzimidazol-2-yl]ethane-1,2-diamine into its molecular formula.
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C21H25ClFN5
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