You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (2S)-2-amino-1-[5,5-dimethyl-2-(2-methylpropyl)-4-oxidopiperazin-4-ium-1-yl]-3-phenylpropan-1-one into molecular formula.
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C19H31N3O2
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