You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(2-methylbut-3-yn-2-yl)-3-propan-2-yl-6,7,8,8a-tetrahydro-3H-pyrrolo[1,2-a]pyrazine-1,4-dione The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H22N2O2
assistant