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system
For the molecule named N-[(1S)-1-(5-chloropyridin-2-yl)-1-[3-fluoro-5-(trifluoromethyl)phenyl]-2-phenylethyl]-3-oxopiperazine-1-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C25H21ClF4N4O2
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