You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2S,3S)-2-(3,4-dimethoxyphenyl)-7-methoxy-2,3-dihydro-1-benzofuran-3-yl]methyl acetate is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22O6
assistant