You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (1R,3aS,3bS,11aS)-1-(methoxymethyl)-11a-methyl-2,3,3a,3b,4,5,8,9,10,11-decahydro-1H-indeno[5,4-f]isochromene .
user
C19H28O2
assistant