You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6aS,7S,11aS)-4-methoxy-2,7-dimethyl-11a-phenyl-6,6a,7,11-tetrahydro-5H-[1,2]benzoxazolo[6,5-h]quinazoline The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H23N3O2
assistant