You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule methyl (4aS,5S,8aR)-5-(benzenesulfonyl)-7-methyl-4-oxo-1,2,3,5,8,8a-hexahydronaphthalene-4a-carboxylate into molecular formula.
user
C19H22O5S
assistant