You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3R,3aR,6R,6aR)-6-[[6-chloro-5-[2-[2-(trifluoromethyl)phenyl]ethyl]-1H-imidazo[4,5-b]pyridin-2-yl]oxy]-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-3-ol by IUPAC nomenclature, provide its molecular formula.
user
C21H19ClF3N3O4
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