You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 4-amino-2-[[5-amino-2-[[2-[(2-amino-3-methylbutanoyl)amino]-3-(1H-imidazol-5-yl)propanoyl]amino]-5-oxopentanoyl]amino]-4-oxobutanoic acid into molecular formula.
user
C20H32N8O7
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