You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name (2S)-2-[[3-[5-(2-cyanoprop-2-enoyloxy)pentoxy]-2-hydroxypropyl]amino]-3-(3,4-dihydroxyphenyl)propanoic acid into its molecular formula.
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C21H28N2O8
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