You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2,2-dimethylpropanoyloxymethyl (1R,2S,3R,4S)-3-methyl-3-(4-methylpiperazine-1-carbonyl)-7-oxabicyclo[2.2.1]heptane-2-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H32N2O6
assistant