You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
butyl 2-[(6aR)-1-hydroxy-9-(methoxymethylidene)-6,6-dimethyl-7,8,10,10a-tetrahydro-6aH-benzo[c]chromen-3-yl]-2-methylpropanoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H36O5
assistant