You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[4-methoxy-3-(4-methylpiperazin-1-yl)phenyl]sulfonyl-6-(trifluoromethyl)-2,3-dihydroindole;hydrochloride into its molecular formula.
user
C21H25ClF3N3O3S
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