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 identified by (1S,3R,3aR,6aS)-5-methyl-1-(3-methylphenyl)-3-pyridin-2-yl-2,3,3a,6a-tetrahydro-1H-pyrrolo[3,4-c]pyrrole-4,6-dione ?
user
C19H19N3O2
assistant