You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[3-(acetylcarbamoyl)-9-(2,6-dimethyl-4-prop-1-ynylphenyl)-10-oxo-3-azaspiro[5.5]undec-8-en-8-yl] acetate is the IUPAC name of a molecule. Please give its molecular formula.
user
C26H30N2O5
assistant