You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule tert-butyl (2S)-6-amino-2-[[(2S)-2-[[(2S)-2-[(2-bromoacetyl)amino]-3-methylbutanoyl]amino]propanoyl]amino]hexanoate into molecular formula.
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C20H37BrN4O5
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