You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl (2S,3R)-2-[(6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-carbonyl)amino]-3-methylpentanoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H28N2O5
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