You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-O-ethyl 2-O-methyl 4-(3,4-dimethoxyphenyl)-1-hydroxy-5,6,7-trimethoxynaphthalene-2,3-dicarboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H28O10
assistant