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)-1-[(1-cyanocyclohexyl)-methylamino]-1-oxopropan-2-yl] 4-(cyclopropylamino)-3-nitrobenzoate into molecular formula.
user
C21H26N4O5
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