You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2R)-N-[(1R,2R,3S)-2,3-dimethylcyclohexyl]-2-[[5-(1H-indol-3-yl)-1,3,4-oxadiazol-2-yl]sulfanyl]propanamide into molecular formula.
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C21H26N4O2S
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