You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-[4-(4-butoxybenzoyl)piperazin-1-yl]-2-[(E)-2-(3-nitrophenyl)ethenyl]-1,3-oxazole-4-carbonitrile into its molecular formula.
user
C27H27N5O5
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