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 (6-methyl-7-oxabicyclo[4.1.0]heptan-3-yl)methyl 4-but-1-en-2-yl-6-methylbicyclo[4.1.0]heptane-3-carboxylate ?
user
C21H32O3
assistant