You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2S)-2-[[(2R)-1-(4-methylpyrazol-1-yl)propan-2-yl]amino]-2-phenyl-N-propan-2-ylacetamide into its molecular formula.
user
C18H26N4O
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