You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4aS,5S,8aS,9aR)-5-hydroxy-9a-methoxy-3,5,8a-trimethyl-4,4a,6,7,8,9-hexahydrobenzo[f][1]benzofuran-2-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H24O4
assistant