You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,8R,9R)-1-acetyl-11-methyl-9-morpholin-4-yltricyclo[6.2.2.02,7]dodeca-2,4,6,11-tetraene-9-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22N2O2
assistant