You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (4R,7aS,12bS)-9-methoxy-3,6-dimethyl-2,4,7a,13-tetrahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinoline into its molecular formula.
user
C19H21NO2
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