You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[[(1S,2R,3R,4aR,9aR)-1,3,4a-trimethyl-1,2,3,4,9,9a-hexahydroxanthen-2-yl]methyl]-N',N'-dimethylpropane-1,3-diamine The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H36N2O
assistant