You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule (1S,2S,4S,6R,8R,9S,10R,12R)-4-(3,4-dimethylphenyl)-5,11-dioxapentacyclo[7.3.1.02,8.04,6.010,12]tridecane-3,7-dione ?
user
C19H18O4
assistant